| Title: | A package for the analysis of GC-MS metabolite profiling data |
|---|---|
| Description: | This packages provides a flexible, fast and accurate method for targeted pre-processing of GC-MS data. The user provides a (often very large) set of GC chromatograms and a metabolite library of targets. The package will automatically search those targets in the chromatograms resulting in a data matrix that can be used for further data analysis. |
| Authors: | Alvaro Cuadros-Inostroza [aut, cre], Jan Lisec [aut], Henning Redestig [aut], Matt Hannah [aut] |
| Maintainer: | Alvaro Cuadros-Inostroza <[email protected]> |
| License: | GPL (>= 2) |
| Version: | 2.9.1 |
| Built: | 2024-11-19 03:34:05 UTC |
| Source: | https://github.com/bioc/TargetSearch |
This packages provides a targeted method for GC-MS data analysis. The workflow includes a peak picking algorithm to convert from netcdf files to tab delimited files, retention time correction using retention time markers provided by the user, and a library search using multiple marker masses and retention time index optimisation.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
Maintainer: Alvaro Cuadros-Inostroza <[email protected]>
This function perform baseline correction by wrapping around the methods
implemented on baselineCorrection and baselineCorrectionQuant.
baseline(ncdf, bsline_method = c('classic', 'quantiles', 'none'), ...)baseline(ncdf, bsline_method = c('classic', 'quantiles', 'none'), ...)
ncdf |
A list containing the raw chromatogram data. The list can be generated by
|
bsline_method |
A string to select the baseline retention method. Options
are |
... |
Extra parameters to be passed to |
.
This is a wrapper function around the different baseline correction algorithms. It is not intended to be executed by the average user. Please refer to the respective man pages for details.
Returns a list with the same elements as the input, but the element "Peaks"
containing baseline corrected values.
Alvaro Cuadros-Inostroza
RIcorrect, baselineCorrection, baselineCorrectionQuant
# get a random sample CDF from TargetSearchData require(TargetSearchData) cdffile <- sample(tsd_cdffiles(), 1) pdata <- peakCDFextraction(cdffile) # restrict mass range to reduce computing time (not needed for # actual data) pdata$Peaks <- pdata$Peaks[, 1:10] ; pdata$massRange <- c(85, 94) # make a fake baseline as constant + noise (the CDF files have been # already baseline corrected by the vendor software). nscans <- length(pdata$Time) noise <- as.integer(1000 + rnorm(nscans, sd=5)) pdata$Peaks <- pdata$Peaks + noise # use Classic and Quantile methods for baseline correction (def parameters) pdata_c <- baseline(pdata, 'classic') # use Quantile method pdata_q <- baseline(pdata, 'quantiles') # plot function to compare traces plfun <- function(p, q, k, n, titl) { plot(p$Time, p$Peaks[, k], col='blue', type='l', xlab='time', ylab='intensity') lines(q$Time, q$Peaks[, k] - n, col='red') legend('topleft', c('corrected', 'original'), col=c('blue', 'red'), lty=1, lwd=2) title(paste('method:', titl)) } op <- par(mfrow=c(2,2)) plfun(pdata_c, pdata, 1, noise, 'classic') plfun(pdata_q, pdata, 1, noise, 'quantile') plfun(pdata_c, pdata, 7, noise, 'classic') plfun(pdata_q, pdata, 7, noise, 'quantile') par(op)# get a random sample CDF from TargetSearchData require(TargetSearchData) cdffile <- sample(tsd_cdffiles(), 1) pdata <- peakCDFextraction(cdffile) # restrict mass range to reduce computing time (not needed for # actual data) pdata$Peaks <- pdata$Peaks[, 1:10] ; pdata$massRange <- c(85, 94) # make a fake baseline as constant + noise (the CDF files have been # already baseline corrected by the vendor software). nscans <- length(pdata$Time) noise <- as.integer(1000 + rnorm(nscans, sd=5)) pdata$Peaks <- pdata$Peaks + noise # use Classic and Quantile methods for baseline correction (def parameters) pdata_c <- baseline(pdata, 'classic') # use Quantile method pdata_q <- baseline(pdata, 'quantiles') # plot function to compare traces plfun <- function(p, q, k, n, titl) { plot(p$Time, p$Peaks[, k], col='blue', type='l', xlab='time', ylab='intensity') lines(q$Time, q$Peaks[, k] - n, col='red') legend('topleft', c('corrected', 'original'), col=c('blue', 'red'), lty=1, lwd=2) title(paste('method:', titl)) } op <- par(mfrow=c(2,2)) plfun(pdata_c, pdata, 1, noise, 'classic') plfun(pdata_q, pdata, 1, noise, 'quantile') plfun(pdata_c, pdata, 7, noise, 'classic') plfun(pdata_q, pdata, 7, noise, 'quantile') par(op)
Function for baseline correction of GC-MS chromatograms using Chang's method described below.
baselineCorrection(peaks, threshold = 0.5, alpha = 0.95, bfraction = 0.2, segments = 100, signalWindow = 10, method = "linear")baselineCorrection(peaks, threshold = 0.5, alpha = 0.95, bfraction = 0.2, segments = 100, signalWindow = 10, method = "linear")
peaks |
Either a matrix object of spectra peak intensities to be baseline corrected,
where the rows are retention times and columns are mass traces; or, a named list containing
an element called |
threshold |
A numeric value between 0 and 1. A value of one sets the baseline above the noise, 0.5 in the middle of the noise and 0 below the noise. |
alpha |
The alpha parameter of the high pass filter. |
bfraction |
The percentage of the fragments with the lowest intensities of the filtered signal that are assumed to be baseline signal. |
segments |
The number of segments in which the filtered signal is divided. |
signalWindow |
The window size (number of points) used in the signal windowing step. |
method |
The method used to approximate the baseline. |
The baseline correction algorithm is based on the work of Chang et al, and it works as
follows. For every mass trace, i.e., columns of matrix peaks, the signal intensity is filtered
by a first high pass filter:
The
filtered signal is divided into evenly spaced segments (segments)
and the standard deviation of each segment is calculated. A percentage (bfraction)
of the segments with the lowest values are assumed to be baseline signal and the
standard deviation () of the points within those segments is calculated.
Once has been determined, the points with absolute filtered values larger than
are considered signal. After that, the signal windowing step takes
every one of the points found to be signal as the center of a signal window (signalWindow)
and marks the points within that window as signal. The remaining points are now considered
to be noise.
The baseline signal is obtained by either using linear interpolation (default)
or fitting a cubic smoothing spline taking only
the noise. The baseline can be shifted up or down by using the parameter
threshold, which is done by the formula:
where
is the fitted spline, the standard deviation of the noise,
and is the threshold between 0 and 1. Finally, the corrected signal
is calculated by subtracting to the original signal.
The output depends on whether the input peaks is a matrix or a list. If it is a matrix,
then the function returns a matrix of the same dimensions with the baseline corrected intensities.
If instead peaks is a list, then the element called "Peaks" will hold the
output.
This function is intended to be run internally, but it is exported for advanced users.
Alvaro Cuadros-Inostroza
David Chang, Cory D. Banack and Sirish L. Shah, Robust baseline correction algorithm for signal dense NMR spectra. Journal of Magnetic Resonance 187 (2007) 288-292
# get a random sample CDF from TargetSearchData require(TargetSearchData) cdffile <- sample(tsd_cdffiles(), 1) pdata <- peakCDFextraction(cdffile) # restrict mass range to reduce computing time (not needed for # actual data) pdata$Peaks <- pdata$Peaks[, 1:10] ; pdata$massRange <- c(85, 94) # make a fake baseline as constant + noise (the CDF files have been # already baseline corrected by the vendor software). nscans <- length(pdata$Time) noise <- as.integer(1000 + rnorm(nscans, sd=5)) pdata$Peaks <- pdata$Peaks + noise # change parameters and see how the results change pdata1 <- baselineCorrection(pdata) pdata2 <- baselineCorrection(pdata, threshold = 1, alpha = 0.97) # pick random trace k k <- 6 m <- cbind(pdata$Peaks[, k] - noise, pdata1$Peaks[, k], pdata2$Peaks[, k]) matplot(pdata$Time, m, type='l', lty=1, xlab='time', ylab='intensity') legend('topleft', c('original', 'base correct 1', 'base correct 2'), col=1:3, lty=1, lwd=1)# get a random sample CDF from TargetSearchData require(TargetSearchData) cdffile <- sample(tsd_cdffiles(), 1) pdata <- peakCDFextraction(cdffile) # restrict mass range to reduce computing time (not needed for # actual data) pdata$Peaks <- pdata$Peaks[, 1:10] ; pdata$massRange <- c(85, 94) # make a fake baseline as constant + noise (the CDF files have been # already baseline corrected by the vendor software). nscans <- length(pdata$Time) noise <- as.integer(1000 + rnorm(nscans, sd=5)) pdata$Peaks <- pdata$Peaks + noise # change parameters and see how the results change pdata1 <- baselineCorrection(pdata) pdata2 <- baselineCorrection(pdata, threshold = 1, alpha = 0.97) # pick random trace k k <- 6 m <- cbind(pdata$Peaks[, k] - noise, pdata1$Peaks[, k], pdata2$Peaks[, k]) matplot(pdata$Time, m, type='l', lty=1, xlab='time', ylab='intensity') legend('topleft', c('original', 'base correct 1', 'base correct 2'), col=1:3, lty=1, lwd=1)
This function perform baseline correction using a quantiles around a moving window algorithm.
baselineCorrectionQuant(peaks, time, smooth=0, qntl=0.50, width=30, unit=c("seconds", "points"), steps=10)baselineCorrectionQuant(peaks, time, smooth=0, qntl=0.50, width=30, unit=c("seconds", "points"), steps=10)
peaks |
Either a matrix object of spectra peak intensities to be baseline corrected,
where the rows are retention times and columns are mass traces; or, a named list containing
an element called |
time |
A vector of retention time in seconds. This parameter is used if |
smooth |
An integer. Smooth each signal by this number of points using a moving average. Smoothing is disabled if this value is less or equal than 1. Note that the smoothing is applied after the baseline correction. |
qntl |
Numeric scalar. The quantile for baseline estimation. The value must be in
|
width |
Numeric scalar. The size of the window centered around a scan for baseline estimation.
The size depends on the parameter |
unit |
A string which chooses if the |
steps |
Integer scalar greater than zero. To speed up computation, the baseline
algorithm does not compute the baseline estimate in each single scan, but in intervals of
|
Applies a quantile based baseline estimation method. The method is applied for each ion
mass trace (column of peaks) individually. It simple computes for each data point of the
trace the qntl quantile, for example the 50% quantile, i.e., the median, of all
the points which are within a width distance or it.
In order for the method to work, select a width much larger than the widest peak.
For speed efficiency, and assuming that the baseline is a smooth curve, the quantiles
are computed every step points. For example, if step=3, then the quantiles
will be computed every third scan instead of every point. If instead step=1, then
it will computed in every scan. The baseline of the points in between (if step > 1)
are approximated by linear interpolation.
Returns a list with the same elements as the input, but the element "Peaks"
containing baseline corrected values. In case peaks is a matrix, it returns a matrix
of the same dimension instead.
Alvaro Cuadros-Inostroza
RIcorrect, baseline, baselineCorrection
# get a random sample CDF from TargetSearchData require(TargetSearchData) cdffile <- sample(tsd_cdffiles(), 1) pdata <- peakCDFextraction(cdffile) # restrict mass range to reduce computing time (not needed for # actual data) pdata$Peaks <- pdata$Peaks[, 1:10] ; pdata$massRange <- c(85, 94) # make a fake baseline as constant + noise (the CDF files have been # already baseline corrected by the vendor software). nscans <- length(pdata$Time) noise <- as.integer(1000 + rnorm(nscans, sd=5)) pdata$Peaks <- pdata$Peaks + noise # change parameters and see how the results change. Note that the default # width of 30 seconds might be too small pdata1 <- baselineCorrectionQuant(pdata, steps=5) pdata2 <- baselineCorrectionQuant(pdata, width=50, steps=5) # pick random trace k and compare correction values k <- 6 m <- cbind(pdata$Peaks[, k] - noise, pdata1$Peaks[, k], pdata2$Peaks[, k]) matplot(pdata$Time, m, type='l', lty=1, xlab='time', ylab='intensity') legend('topleft', c('original', 'base correct 1', 'base correct 2'), col=1:3, lty=1, lwd=1)# get a random sample CDF from TargetSearchData require(TargetSearchData) cdffile <- sample(tsd_cdffiles(), 1) pdata <- peakCDFextraction(cdffile) # restrict mass range to reduce computing time (not needed for # actual data) pdata$Peaks <- pdata$Peaks[, 1:10] ; pdata$massRange <- c(85, 94) # make a fake baseline as constant + noise (the CDF files have been # already baseline corrected by the vendor software). nscans <- length(pdata$Time) noise <- as.integer(1000 + rnorm(nscans, sd=5)) pdata$Peaks <- pdata$Peaks + noise # change parameters and see how the results change. Note that the default # width of 30 seconds might be too small pdata1 <- baselineCorrectionQuant(pdata, steps=5) pdata2 <- baselineCorrectionQuant(pdata, width=50, steps=5) # pick random trace k and compare correction values k <- 6 m <- cbind(pdata$Peaks[, k] - noise, pdata1$Peaks[, k], pdata2$Peaks[, k]) matplot(pdata$Time, m, type='l', lty=1, xlab='time', ylab='intensity') legend('topleft', c('original', 'base correct 1', 'base correct 2'), col=1:3, lty=1, lwd=1)
A function to visually check if the retention time search limits of the retention index markers (aka FAMEs) are correct or need some adjustment.
checkRimLim(samples, rim, layout, show = TRUE, single = TRUE, extend = 0.5, rect.col = "#e7e7e7", mar = c(2, 2, 2, 2), oma = c(3, 3, 2, 0.5), cex.main = 1, type = "l", ...)checkRimLim(samples, rim, layout, show = TRUE, single = TRUE, extend = 0.5, rect.col = "#e7e7e7", mar = c(2, 2, 2, 2), oma = c(3, 3, 2, 0.5), cex.main = 1, type = "l", ...)
samples |
A |
rim |
A |
layout |
A vector of the form |
show |
Logical. If |
single |
Logical. If |
extend |
a numeric coefficient to extend the time window search of the
respective time marker. Defaults to |
rect.col |
the color for the background rectangle which indicates the current retention time limits. |
mar |
the subplots margins, passed to |
oma |
the outer plot margins, passed to |
cex.main |
The magnification to be used for main titles, passed to
|
type |
A character vector indicating the type of plots. Default |
... |
extra plotting arguments passed to |
The function takes a tsSample object and creates a panel
plot of the m/z traces around the area in which a marker is expected to be,
one panel for each marker. By default, a single (random) sample is chosen (see
option single) for plotting, but it is also possible to visualize many
samples at the same time (but see note below).
For multiple sample visualization, it is recommended to use sub-setting for the
samples and rim arguments in order to avoid over crowded plots,
specially when there are several samples and several retention index markers.
See the examples below.
Plotting options such as col, lty, pch, lwd can
be passed; these are in turn passed to matplot().
Note that these are passed to each panel; it not possible to pass different
options to different panels (for example to have different line colors).
Moreover, using options such as xlim and ylim may result in
‘empty’ plots (because each panel needs its own limits). If different
styles are required, then either make your own function from the output or
use subsets of the rim (tsRim) object.
The output value is either invisible or it depends on the option single.
If this option is TRUE (the old behavior), then the output will be a list
of n times 2 matrices, each element corresponding to a retention marker.
Columns are retention time and intensities of the respective marker's m/z. The rows
can be as many data points are within the search window.
If single=FALSE, the output is a list whose length is equal
to length(samples) and its names are equal to sampleNames(samples).
Each element is in turn a list with exactly the same structure described in the
paragraph above.
If single=TRUE, all CDF files will be scanned, which can
take a significant amount of time to parse, in particular, if there are
hundred of them. Also due to this, each panel of the plot could be extremely
crowded. It is therefore recommended to use sample sub-setting to reduce
this number, as shown in the examples below.
matplot for plotting parameters,
par for inner and outer margins parameters,
tsSample,
sampleNames,
tsRim,
ImportFameSettings
require(TargetSearchData) # get the cdf path TargetSearchData cdfpath <- tsd_data_path() # import samples (see ImportSamples() for details) samples <- ImportSamples(tsd_file_path("samples.txt"), CDFpath = cdfpath) # Import RI markers (see ImportFameSettings()) rim <- ImportFameSettings(tsd_file_path("rimLimits.txt")) # choose a sample at random and plot the m/z traces around the retention time window ret <- checkRimLim(samples, rim) # to choose a specific sample and marker, use subsetting ret <- checkRimLim(samples[3], rim[1:2]) # to display many samples at the same time, set the option `single` to `FALSE` and select a subset # of samples (recommended). In this example the first three samples are chosen. ret <- checkRimLim(samples[1:3], rim, single=FALSE) # in general, visualizing all samples (as shown below) at the same time it is not recommended # for large number of samples. ## Not run: ret <- checkRimLim(samples, rim, single=FALSE) ## End(Not run)require(TargetSearchData) # get the cdf path TargetSearchData cdfpath <- tsd_data_path() # import samples (see ImportSamples() for details) samples <- ImportSamples(tsd_file_path("samples.txt"), CDFpath = cdfpath) # Import RI markers (see ImportFameSettings()) rim <- ImportFameSettings(tsd_file_path("rimLimits.txt")) # choose a sample at random and plot the m/z traces around the retention time window ret <- checkRimLim(samples, rim) # to choose a specific sample and marker, use subsetting ret <- checkRimLim(samples[3], rim[1:2]) # to display many samples at the same time, set the option `single` to `FALSE` and select a subset # of samples (recommended). In this example the first three samples are chosen. ret <- checkRimLim(samples[1:3], rim, single=FALSE) # in general, visualizing all samples (as shown below) at the same time it is not recommended # for large number of samples. ## Not run: ret <- checkRimLim(samples, rim, single=FALSE) ## End(Not run)
A function to detect retention time marker (FAME) outliers.
FAMEoutliers(samples, RImatrix, pdffile = NA, startDay = NULL, endDay = NULL, threshold = 3, group.threshold = 0.05)FAMEoutliers(samples, RImatrix, pdffile = NA, startDay = NULL, endDay = NULL, threshold = 3, group.threshold = 0.05)
samples |
A |
RImatrix |
A retention time matrix of the found retention time markers. |
pdffile |
A character string naming a PDF file where the FAMEs report will be saved. |
startDay |
A character vector with the starting days of your day groups. |
endDay |
A character vector with the ending days of your day groups. |
threshold |
A standard deviations cutoff to detect outliers. |
group.threshold |
A numeric cutoff to detect day groups based on hierarchical
clustering. Must be between |
If no pdffile argument is given, the report will be saved on a file called
"TargetSearch-YYYY-MM-DD.FAME-report.pdf", where YYYY-MM-DD is a
date.
If both startDay and endDay are not given (both set to either
NULL or NA), the function will try
to detect day groups using a hierarchical clustering approach by cutting the tree
using group.threshold as cutoff height. Otherwise, both must have the
same length, must not contain NAs, and must match the measurement days
of the object samples. See example below.
Retention time markers that deviate more than threshold standard
deviations from the mean of their day group will be identified as outliers.
A logical matrix of the same size of RImatrix. A TRUE value indicates
that the retention time marker in that particular sample is an outlier.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
RIcorrect, ImportSamples, TSExample
# load pre-calculated example data and objects data(TSExample) # find the retention marker outliers of the example data and save it in "outlier.pdf" outliers <- FAMEoutliers(sampleDescription, RImatrix, pdffile = "outlier.pdf") # find the outliers (although they are reported in the output PDF file) apply(outliers, 1, which) # using `startDay` and `endDay` to set day groups manually sampleDays(sampleDescription) <- rep(letters[1:3], each=5) # make fake days a, b, c # set days 'a' and 'b' in a group and day 'c' by itself startDay <- c('a', 'c') endDay <- c('b', 'c') outliers <- FAMEoutliers(sampleDescription, RImatrix, pdffile="outlier.pdf", startDay=startDay, endDay=endDay)# load pre-calculated example data and objects data(TSExample) # find the retention marker outliers of the example data and save it in "outlier.pdf" outliers <- FAMEoutliers(sampleDescription, RImatrix, pdffile = "outlier.pdf") # find the outliers (although they are reported in the output PDF file) apply(outliers, 1, which) # using `startDay` and `endDay` to set day groups manually sampleDays(sampleDescription) <- rep(letters[1:3], each=5) # make fake days a, b, c # set days 'a' and 'b' in a group and day 'c' by itself startDay <- c('a', 'c') endDay <- c('b', 'c') outliers <- FAMEoutliers(sampleDescription, RImatrix, pdffile="outlier.pdf", startDay=startDay, endDay=endDay)
This function extracts all peaks of a given metabolite in a given retention time (RT) or retention index (RI) window. This function is intended for fine-tuning metabolite search parameters.
FindAllPeaks(samples, Lib, libID, dev=NULL, mz=NULL, RI=NULL, RT=NULL, mz_type = c('selMass', 'quantMass', 'topMass'), columns = NULL)FindAllPeaks(samples, Lib, libID, dev=NULL, mz=NULL, RI=NULL, RT=NULL, mz_type = c('selMass', 'quantMass', 'topMass'), columns = NULL)
samples |
A |
Lib |
A |
libID |
An index (integer or character) value representing the respective metabolite in
the reference library |
dev |
The allowed retention index (RI) deviation or |
mz |
A list of m/z values to search or |
RI |
The expected retention index or |
RT |
The expected retention time to search for instead of retention index, or |
mz_type |
whether to search for the selective, quantification or top masses of the respective metabolite. |
columns |
Either |
The function searches for all peaks of a metabolite in all samples within a time
window (RT or RI). The parameters dev, mz, RI, and RT have preference over
the settings of the metabolite indexed by libID. Moreover, the parameter RI has
preference of over RT (see below). In fact, if all of these parameters are not
NULL, then refLib and libID are not used.
The metabolite search can be performed using retention index (RI) or retention time (RT).
To search using RI, either specify the value by setting RI, or set both RI and
RT to NULL, which defaults to searching by the library RI. To search using RT,
you must set RI to NULL and set dev to a value (i.e., not NULL),
otherwise an error will be thrown. See examples below.
The dev parameter can either be NULL (as stated above), or a numeric vector.
If the length is equal to 1, then the RI search window is the given RI
plus or minus dev. If the length is 2, then the search window is from RI + dev[1]
to RI + dev[2]. Note than in this case dev[1] is usually a negative value.
An error is raised if the length is greater than 2. Note that as mentioned above, this
parameter is required to search by RT. Needless to say, the dev parameter units should
correspond with the units of RI or RT accordingly.
The columns parameter is only needed for custom text RI files. There is (usually)
no need to change it.
It returns a matrix in which each row represent a hit. Note that there can be zero rows if no hits are found. The columns are named and these are:
Int |
Peak intensity |
RI |
Retention Index |
RI |
Retention Time |
mz |
the searched m/z value |
fid |
the respective file or sample index. An integer value. |
This is an internal function not intended to be invoked directly, but it is exposed for convenience and advanced users.
In the future it may replace FindPeaks.
See also the function ri_data_extract which offers a similar functionality
but with different input parameters.
Alvaro Cuadros-Inostroza
# load pre-calculated example data files and objects require(TargetSearchData) data(TSExample) # get and set the RI file path RIpath(sampleDescription) <- tsd_data_path() # search all peaks of Valine (GC.3) and selective masses peaks <- FindAllPeaks(sampleDescription, refLibrary, 'GC.3') head(peaks) # a numeric index is also allowed peaks <- FindAllPeaks(sampleDescription, refLibrary, 3) head(peaks) # an asymmetric deviation search peaks <- FindAllPeaks(sampleDescription, refLibrary, 'GC.3', dev=c(-1000, 2000)) head(peaks) # search arbitrary masses at arbitrary RI. The reference library and ID # must be set set to NULL. peaks <- FindAllPeaks(sampleDescription, NULL, NULL, dev=3000, RI=270000, mz=c(144, 100)) head(peaks) # to search for RT, set the RT parameter to not NULL peaks <- FindAllPeaks(sampleDescription, refLibrary, 'GC.3', dev=3.0, RT=250) peaks <- FindAllPeaks(sampleDescription, NULL, NULL, dev=3.0, RT=250, mz=c(144, 100)) ## Not run: # note that 'dev' is required; this throws an error peaks <- FindAllPeaks(sampleDescription, NULL, NULL, RT=250, mz=c(144, 100)) ## End(Not run)# load pre-calculated example data files and objects require(TargetSearchData) data(TSExample) # get and set the RI file path RIpath(sampleDescription) <- tsd_data_path() # search all peaks of Valine (GC.3) and selective masses peaks <- FindAllPeaks(sampleDescription, refLibrary, 'GC.3') head(peaks) # a numeric index is also allowed peaks <- FindAllPeaks(sampleDescription, refLibrary, 3) head(peaks) # an asymmetric deviation search peaks <- FindAllPeaks(sampleDescription, refLibrary, 'GC.3', dev=c(-1000, 2000)) head(peaks) # search arbitrary masses at arbitrary RI. The reference library and ID # must be set set to NULL. peaks <- FindAllPeaks(sampleDescription, NULL, NULL, dev=3000, RI=270000, mz=c(144, 100)) head(peaks) # to search for RT, set the RT parameter to not NULL peaks <- FindAllPeaks(sampleDescription, refLibrary, 'GC.3', dev=3.0, RT=250) peaks <- FindAllPeaks(sampleDescription, NULL, NULL, dev=3.0, RT=250, mz=c(144, 100)) ## Not run: # note that 'dev' is required; this throws an error peaks <- FindAllPeaks(sampleDescription, NULL, NULL, RT=250, mz=c(144, 100)) ## End(Not run)
This function extracts the maximum intensity of a list of masses in a given RI window.
FindPeaks(my.files, refLib, columns = NULL, showProgressBar = FALSE)FindPeaks(my.files, refLib, columns = NULL, showProgressBar = FALSE)
my.files |
A character vector naming RI files to be searched. |
refLib |
A numeric matrix with three columns or a list of three column matrices. The second column contains the masses and the first and third column contains the RI limits. |
showProgressBar |
Logical. Should the progress bar be displayed? |
columns |
Either |
The reference library parameter refLib can be either a single
three-column matrix or a list of such matrices. If it is a list, the length
must match the length of my.files. In this case, every component will
be used to iteratively search in the corresponding file.
The RI files format can be either "text" or "binary". The type is detected dynamically.
A tsMSdata object.
This is an internal function not intended to be invoked directly.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
medianRILib, sampleRI,
peakFind, tsMSdata
# load example CDF files require(TargetSearchData) # load pre-calculated example data and objects data(TSExample) # get RI file path RI.path <- tsd_data_path() # update RI file path RIpath(sampleDescription) <- RI.path my.files <- RIfiles(sampleDescription) # make a three column matrix: lower RI, mass, upper RI refLib <- refLib(refLibrary) head(refLib) # extract the peaks peaks <- FindPeaks(my.files, refLib)# load example CDF files require(TargetSearchData) # load pre-calculated example data and objects data(TSExample) # get RI file path RI.path <- tsd_data_path() # update RI file path RIpath(sampleDescription) <- RI.path my.files <- RIfiles(sampleDescription) # make a three column matrix: lower RI, mass, upper RI refLib <- refLib(refLibrary) head(refLib) # extract the peaks peaks <- FindPeaks(my.files, refLib)
This function can be used to correct the detected retention time index (RI) markers or to manually force their location to specific retention times if, for example, the RI markers were not co-injected with the biological samples.
fixRI(samples, rimLimits, RImatrix=NULL, sampleNames=NULL, quiet=TRUE)fixRI(samples, rimLimits, RImatrix=NULL, sampleNames=NULL, quiet=TRUE)
samples |
A |
rimLimits |
A |
RImatrix |
Optional. A retention time matrix of the found retention time markers that
was obtained after running |
sampleNames |
Optional. A character vector naming the samples that are to be RI corrected. |
quiet |
Logical. Do not print a list of converted files. |
Sometimes the retention index limits (see ImportFameSettings)
are not set correctly and you will have to run the peak detection and RI
correction function (RIcorrect) again, which may take a
long time specially if there are many samples.
Instead, a simple approach is to fix the RI limits and use this function to correct the generated RI files. Since these files are much smaller than CDF files (chromatograms), this runs much faster.
Other possibility is that the time positions of one or more RI markers were wrongly detected because there was just simply no peak or the RI markers where not co-injected in some samples. You could manually force the locations of the RI markers. This case is discussed in the “RICorrection” vignette.
The behavior of this function depends on whether the parameter RImatrix
is NULL or not. If NULL, the RI markers will be searched again
(using the settings of rimLimits parameters, which you should have already
fixed) and the resulting values will be used to correct the RI files.
If it is a numeric matrix, then these values will be used to correct the
RI files. Note that this matrix dimensions are exactly m samples (rows)
times n (columns) RI markers.
sampleNames controls which samples will be corrected. If NULL
then all samples will be corrected. It could be character vector (sample
names) or a numeric vector representing the sample indexes.
Invisible NULL. It prints the corrected samples if quiet is
FALSE.
In case the RI files are in text format and their column names are not standard (for
example, when the files were generated with another software), use the global option
'TS_RI_columns' or transform the RI files to TargetSearch binary
format. See the documentation in function text2bin.
Alvaro Cuadros-Inostroza
RIcorrect, FAMEoutliers,ImportSamples,
ImportFameSettings
require(TargetSearchData) # import refLibrary, rimLimits and sampleDescription. data(TSExample) # get the CDF files cdfpath <- tsd_data_path() # select a subset of samples smp <- sampleDescription[1:4] # update the CDF path CDFpath(smp) <- cdfpath # make a copy of the RI markers object rim <- rimLimits # mess up the limits of marker 3 (real value is 369 seconds app.) rimLimits(rim)[3,] <- c(375, 400) # run RIcorrect (skip CDF-4 conversion) RImat <- RIcorrect(smp, rim, writeCDF4path=FALSE, Window = 15, IntThreshold = 50) # fix the limits of marker 3 rimLimits(rim)[3,] <- c(360, 400) # you could run again RIcorrect, but this is faster fixRI(smp, rim) # get the RI matrix RImat <- riMatrix(smp, rim) # compare the values with the real ones (previously stored in RImatrix) stopifnot( all.equal(RImat, RImatrix[,1:4], tolerance=1e-8) ) # manual adjustment or RI markers for sample 3. # Warning: this is just an example to illustrate how to use this function. # don't do this unless you know what you're doing. RImat[,3] <- c(252, 311, 369) fixRI(smp, rim, RImat, 3)require(TargetSearchData) # import refLibrary, rimLimits and sampleDescription. data(TSExample) # get the CDF files cdfpath <- tsd_data_path() # select a subset of samples smp <- sampleDescription[1:4] # update the CDF path CDFpath(smp) <- cdfpath # make a copy of the RI markers object rim <- rimLimits # mess up the limits of marker 3 (real value is 369 seconds app.) rimLimits(rim)[3,] <- c(375, 400) # run RIcorrect (skip CDF-4 conversion) RImat <- RIcorrect(smp, rim, writeCDF4path=FALSE, Window = 15, IntThreshold = 50) # fix the limits of marker 3 rimLimits(rim)[3,] <- c(360, 400) # you could run again RIcorrect, but this is faster fixRI(smp, rim) # get the RI matrix RImat <- riMatrix(smp, rim) # compare the values with the real ones (previously stored in RImatrix) stopifnot( all.equal(RImat, RImatrix[,1:4], tolerance=1e-8) ) # manual adjustment or RI markers for sample 3. # Warning: this is just an example to illustrate how to use this function. # don't do this unless you know what you're doing. RImat[,3] <- c(252, 311, 369) fixRI(smp, rim, RImat, 3)
This function imports a list of retention standard markers for RI correction.
ImportFameSettings(file, mass=NULL, standard=NULL, colnames=FALSE, ...)ImportFameSettings(file, mass=NULL, standard=NULL, colnames=FALSE, ...)
file |
A character string naming a tab-delimited text file with standard markers OR a matrix-like object. |
mass |
Optional. The m/z standard marker(s). Either a scalar, which applies to every marker, or a vector. |
standard |
Optional. The RI values of the standards. A numeric vector. |
colnames |
Logical flag. If |
... |
Options passed to |
The standard marker file is a tab-delimited text file with 2, 3 or 4
columns. Additional columns are ignored. If the parameter colnames
is FALSE, then the column names are ignored and they must be in the
following specified below. If TRUE, use the column names below (case
is ignored). Note that some columns are optional as they can be specified by
the options mass and standard.
LowerLimit - The Retention time lower limit in seconds
(required).
UpperLimit - The Retention time upper limit in seconds
(required).
RIstandard - The RI value of that standard. This is optional
(option standard).
mass - The m/z standard marker. This is optional
(option mass).
Instead of passing a file via the file option, one can pass a
matrix or a data.frame, The same aforementioned conditions
apply in terms of column names and number.
In general, the mass and the standard should be to NULL.
If not, then they take precedence over the values defined by the file
parameter.
If no arguments are given, a default object will be returned.
A tsRim object.
If the parameter colnames is set to TRUE, then care needs to be
taken regarding the column names: they must be named exactly as described in
the details section, otherwise they can be silently ignored and a
default value might be used instead. This has been the default behavior.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
require(TargetSearchData) # get the RI marker definition file rim.file <- tsd_file_path("rimLimits.txt") # set the mass marker to 87 mass <- 87 # load the definition rimLimits <- ImportFameSettings(rim.file, mass = mass) # sometimes you need to change the limits of a particular standard rimLimits(rimLimits)[2,] <- c(410, 450) # to change the mass value rimMass(rimLimits) <- 85 # alternatively, you can pass a two column matrix as limits and pass the # rest as parameters separately (toy example). limits <- cbind(c(10, 20, 30), c(15, 25, 35)) mass <- 100 standard <- c(100, 200, 300) rimLimits <- ImportFameSettings(limits, mass, standard) # or combine all into a matrix (note the column order!) def <- cbind(limits, standard, mass) rimLimits <- ImportFameSettings(def)require(TargetSearchData) # get the RI marker definition file rim.file <- tsd_file_path("rimLimits.txt") # set the mass marker to 87 mass <- 87 # load the definition rimLimits <- ImportFameSettings(rim.file, mass = mass) # sometimes you need to change the limits of a particular standard rimLimits(rimLimits)[2,] <- c(410, 450) # to change the mass value rimMass(rimLimits) <- 85 # alternatively, you can pass a two column matrix as limits and pass the # rest as parameters separately (toy example). limits <- cbind(c(10, 20, 30), c(15, 25, 35)) mass <- 100 standard <- c(100, 200, 300) rimLimits <- ImportFameSettings(limits, mass, standard) # or combine all into a matrix (note the column order!) def <- cbind(limits, standard, mass) rimLimits <- ImportFameSettings(def)
These functions import a metabolite library file that will be used to processed the GC-MS data. Two file formats are supported: a tab-delimited format and the more common NIST MSP format.
ImportLibrary(x, type = c("auto", "tab", "msp"), ...) ImportLibrary.tab(libfile, fields = NULL, RI_dev = c(2000,1000,200), SelMasses = 5, TopMasses = 15, ExcludeMasses = NULL, libdata, file.opt=NULL) ImportLibrary.msp(libfile, fields = NULL, RI_dev = c(2000,1000,200), SelMasses = 5, TopMasses = 15, ExcludeMasses = NULL)ImportLibrary(x, type = c("auto", "tab", "msp"), ...) ImportLibrary.tab(libfile, fields = NULL, RI_dev = c(2000,1000,200), SelMasses = 5, TopMasses = 15, ExcludeMasses = NULL, libdata, file.opt=NULL) ImportLibrary.msp(libfile, fields = NULL, RI_dev = c(2000,1000,200), SelMasses = 5, TopMasses = 15, ExcludeMasses = NULL)
x |
A character string or a |
libfile |
A character string naming a library file. See details. |
type |
The library file format. Possible options are |
fields |
A two component list. Each component contains a regular expression used to parse and extract the fields for retention index and selection masses. Only meaningful for MSP format. |
RI_dev |
A three component vector with RI windows. |
SelMasses |
The number of selective masses that will be used. |
TopMasses |
The number of most intensive masses that will be taken from the spectrum,
if no |
ExcludeMasses |
Optional. A vector containing a list of masses that will be excluded. |
libdata |
Optional. A data frame with library data. The format is the same
as the library file. It is equivalent to importing the library file first
with |
file.opt |
Optional. A list containing arguments to be passed to
|
... |
Further arguments passed to |
ImportLibrary is a wrapper for functions ImportLibrary.tab and
ImportLibrary.msp which detects automatically which function should be
called.
ImportLibrary.tab reads a tab delimited text file by calling the function
read.table which will be parsed and converted to a
tsLib object. The following arguments are used by default
(which are not exactly the defaults for read.table):
header=TRUE, sep="\t", quote="", dec=".", fill=TRUE, comment.char="#"
The argument file.opt can be used to change these options. Other
alternative is to import first the file with read.table and
friends, and call ImportLibrary with the resulting data.frame.
This allows more flexibility with libraries with unusual characters, for
example.
These columns are needed:
libID - A unique identifier for the metabolite.
Name - The metabolite name.
RI - The expected RI.
SEL_MASS - A list of selective masses separated with semicolon.
TOP_MASS - A list of the most abundant masses to be searched, separated
with semicolons.
Win_k - The RI windows, k = 1,2,3. Mass search is performed in three
steps. A RI window required for each one of them.
SPECTRUM - The metabolite spectrum. m/z and intensity values
are separated by spaces, colons or semicolons (see notes on the format below).
QUANT_MASS - A list of masses that might be used for quantification.
One value per metabolite and it must be one of the selective masses. (optional)
The columns Name and RI are mandatory. At least one of columns SEL_MASS,
TOP_MASS and SPECTRUM must be given as well. By using the
parameters SelMasses or TopMasses it is possible to set the selective
masses or the top masses from the spectra. The parameter ExcludeMasses is
used only when masses are obtained from the spectra.
The parameter RI_dev can be used to set the RI windows.
Note that in this case, all metabolites would have the same RI windows.
The SPECTRUM format can be a list of m/z-intensity pairs separated
by colons: 85:8 86:13 87:5 88:4 ..., or similar to the MSP spectrum format (shown
below): 85 8; 86 13; 87 5; 88 4; .... The internal parser is not strict,
so even a list of integers separated by spaces is allowed, for example,
86 8 86 13 .... The only restriction is that the number of integers is even,
otherwise the input is truncated. If the spectrum is not available for some analytes,
simply leave the respective cell empty or use NA. Note: Only
digits(0-9), spaces, colons(:) and semicolons(;) are allowed in this column; the
presence of other characters will generate and error, unless it is NA.
A unique identifier may be provided as well (libID). This could be a
external database identifier. If it is not provided, a random identifier will be created
of the form GC.k, k = 1,...,N.
The MSP format is a text file that can be imported/exported from NIST. A typical MSP file looks like this:
Name: Pyruvic Acid Synon: Propanoic acid, 2-(methoxyimino)-, trimethylsilyl ester Synon: RI: 223090 Synon: SEL MASS: 89|115|158|174|189 Formula: C7H15NO3Si MW: 189 Num Peaks: 41 85 8; 86 13; 87 5; 88 4; 89 649; 90 55; 91 28; 92 1; 98 13; 99 257; 100 169; 101 30; 102 7; 103 13; 104 1; 113 3; 114 35; 115 358; 116 44; 117 73; 118 10; 119 4; 128 2; 129 1; 130 10; 131 3; 142 1; 143 19; 144 4; 145 1; 157 1; 158 69; 159 22; 160 4; 173 1; 174 999; 175 115; 176 40; 177 2; 189 16; 190 2; Name: another metabolite ...
Different entries must be separated by empty lines. In order to parse the retention
time index (RI) and selective masses (SEL MASS), a two component list
containing the field names of RI and SEL_MASS must be provided by using the
parameter fields. In this example, use field = list("RI: ", "SEL MASS: ").
Note that ImportLibrary expects to find those fields next to "Synon:".
Alternatively, you could provide the RI and SEL_MASS using the tsLib
methods.
Libraries for TargetSearch and for different retention index systems, such as VAR5 or MDN35, can be downloaded from http://gmd.mpimp-golm.mpg.de/.
A tsLib object.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
# get the reference library file require(TargetSearchData) lib.file <- tsd_file_path("library.txt") # Import the reference library refLibrary <- ImportLibrary(lib.file) # set new names for the first 3 metabolites libName(refLibrary)[1:3] <- c("Metab01", "Metab02", "Metab03") # change the retention time deviations of Metabolite 3 RIdev(refLibrary)[3,] <- c(3000,1500,150)# get the reference library file require(TargetSearchData) lib.file <- tsd_file_path("library.txt") # Import the reference library refLibrary <- ImportLibrary(lib.file) # set new names for the first 3 metabolites libName(refLibrary)[1:3] <- c("Metab01", "Metab02", "Metab03") # change the retention time deviations of Metabolite 3 RIdev(refLibrary)[3,] <- c(3000,1500,150)
These functions import sample information from either a tab delimited file or a file system path. The sample information contain sample names, CDF files and their measurement day, also known as, measurement run or measurement batch.
ImportSamples(sampfile, CDFpath, RIpath, ftype=c("binary", "text"), ...) ImportSamplesFromDir(CDFpath=".", RIfiles=FALSE, ftype=c("binary", "text"), verbose=FALSE, ...)ImportSamples(sampfile, CDFpath, RIpath, ftype=c("binary", "text"), ...) ImportSamplesFromDir(CDFpath=".", RIfiles=FALSE, ftype=c("binary", "text"), verbose=FALSE, ...)
sampfile |
A character string naming a sample file or a |
CDFpath |
A character string naming a directory where the CDF files are located (by default is the current directory) |
RIpath |
A character string naming a directory where the RI corrected text files are/will be located. |
RIfiles |
Logical. If |
ftype |
A character string giving the file type for RI files. Options are "binary" and "text". |
verbose |
Logical. Show more output if |
... |
Extra options whose meaning depend on the function: for |
.
The sample file is a tab-delimited text file or, alternatively, a
data.frame like the one would get by calling
read.delim. The following columns
are expected, though only the first one below is mandatory.
CDF_FILE - The list of baseline corrected CDF files (mandatory).
MEASUREMENT_DAY - The day or batch when the sample was measured (optional).
SAMPLE_NAME - A unique sample identifier (optional).
The function first looks for columns matching those names. If they are not found, then it looks for columns with the substrings 'cdf', 'day' and 'name' respectively. If the 'cdf' column is not found, the function raises an error, but if 'day' is not found, then it assumes the measurement day is the same for all. Moreover, if the column for sample names/identifiers is missing, then the function uses the 'cdf' file names as identifiers.
During the column matching, the first match is taken in case of ambiguity. The column order does not matter. Other columns could be included in that file. They won't be used by the script, but will be included in the "sample" R object.
The files given in the 'cdf' column may optionally include a relative path,
such as mypath/myfile.cdf, which will be relative to the working
directory or relative to the argument CDFpath. Optionally, the
file extension can be omitted because ‘TargetSearch’ adds the .cdf
extension automatically if missing. Note: it may fail in case sensitive
file systems as a lower case extension is appended.
If the parameter CDFpath is missing, then the current directory
is used. If RIpath is missing, the value of CDFpath will
be used.
The ftype parameter sets the file format of the RI files, which
are created by the function RIcorrect. "text" is the
classic text format and "binary" is a binary version, designed
for speed, of the text format (TargetSearch >= 1.12.0). The file format
can be identified by the file extension (".txt" for text, ".dat" for
binary), but this is just an indicator: the file format is detected
dynamically during file reading. Use the method fileFormat
to set or get this parameter.
The function ImportSamplesFromDir scans for cdf files in the current
or given directory. The search can be made recursive by passing the
parameter recursive=TRUE (actually passed to dir).
The parameter verbose will print a list of detected files
is set to TRUE. This can be used for debugging.
A tsSample object.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
# get the sample definition definition file require(TargetSearchData) cdfpath <- tsd_data_path() sample.file <- tsd_file_path("samples.txt") # set a path where the RI files will be created RIpath <- "." # import samples sampleDescription <- ImportSamples(sample.file, CDFpath = cdfpath, RIpath = RIpath) # change the sample names. It is required that the names must be unique. sampleNames(sampleDescription) <- paste("Sample", 1:length(sampleDescription), sep = "_") # change the file paths (relative to the working path) CDFpath(sampleDescription) <- "my_cdfs" RIpath(sampleDescription) <- "my_RIs"# get the sample definition definition file require(TargetSearchData) cdfpath <- tsd_data_path() sample.file <- tsd_file_path("samples.txt") # set a path where the RI files will be created RIpath <- "." # import samples sampleDescription <- ImportSamples(sample.file, CDFpath = cdfpath, RIpath = RIpath) # change the sample names. It is required that the names must be unique. sampleNames(sampleDescription) <- paste("Sample", 1:length(sampleDescription), sep = "_") # change the file paths (relative to the working path) CDFpath(sampleDescription) <- "my_cdfs" RIpath(sampleDescription) <- "my_RIs"
A function that makes an index for selective or top masses.
Replaces the method libId.
makeIndex(lib, sel=TRUE)makeIndex(lib, sel=TRUE)
lib |
A tsLib object. |
sel |
A logical flag. If |
This is an internal function that should not be used. It is exposed
because the method it replaces, libId, was originally
exposed, so compatibility is not lost.
An integer vector, where each number is associated with an element of the library object, and its multiplicity with the number of selective or top masses.
It is equivalent to the deprecated method libId.
Alvaro Cuadros-Inostroza
# load example objects data(TSExample) # generate an index for selective masses (idx <- makeIndex(refLibrary, TRUE))# load example objects data(TSExample) # generate an index for selective masses (idx <- makeIndex(refLibrary, TRUE))
Return a tsLib object with the median RI of the selective masses across samples.
medianRILib(samples, Lib, makeReport = FALSE, pdfFile = "medianLibRep.pdf", columns = NULL, showProgressBar = FALSE)medianRILib(samples, Lib, makeReport = FALSE, pdfFile = "medianLibRep.pdf", columns = NULL, showProgressBar = FALSE)
samples |
A |
Lib |
A |
makeReport |
Logical. If |
pdfFile |
The file name where the report will be saved. |
columns |
Either |
showProgressBar |
Logical. Should the progress bar be displayed? |
A tsLib object. It will update the slot med_RI which contains
the median RI of every searched metabolite.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
ImportSamples, ImportLibrary, tsLib-class
require(TargetSearchData) data(TSExample) # get RI file path RI.path <- tsd_data_path() # update RI file path RIpath(sampleDescription) <- RI.path # Import Library refLibrary <- ImportLibrary(tsd_file_path('library.txt')) # update median RI refLibrary <- medianRILib(sampleDescription, refLibrary) # perhaps you need to adjust the library RI of one metabolite and the allowed time # deviation (first time deviation window) libRI(refLibrary)[5] <- 306500 RIdev(refLibrary)[5,1] <- 2000 refLibrary <- medianRILib(sampleDescription, refLibrary)require(TargetSearchData) data(TSExample) # get RI file path RI.path <- tsd_data_path() # update RI file path RIpath(sampleDescription) <- RI.path # Import Library refLibrary <- ImportLibrary(tsd_file_path('library.txt')) # update median RI refLibrary <- medianRILib(sampleDescription, refLibrary) # perhaps you need to adjust the library RI of one metabolite and the allowed time # deviation (first time deviation window) libRI(refLibrary)[5] <- 306500 RIdev(refLibrary)[5,1] <- 2000 refLibrary <- medianRILib(sampleDescription, refLibrary)
Convert from NetCDF format 3 into a custom TargetSearch NetCDF format 4. The new NetCDF just contains the raw data in a matrix format in order to allow easier and faster data manipulation.
ncdf4_convert(cdfFile, outFile = NULL, force = FALSE, baseline = FALSE, ...)ncdf4_convert(cdfFile, outFile = NULL, force = FALSE, baseline = FALSE, ...)
cdfFile |
The NetCDF file to be converted |
outFile |
The new output file. If |
force |
Logical. Set to |
baseline |
Logical. Whether or not baseline correct the input file. |
... |
extra options passed to |
Starting from version 1.42.0, TargetSearch introduces a custom NetCDF file which is used for faster and easier data manipulation. This means, ion traces within a retention time can be quickly extracted, which if often required before plotting. Formerly, this process required parsing the whole file before the data could be extracted.
Note that this function only takes one file at the time. To convert many files at the
same time, see the function ncdf4_convert_from_path() or the high level method
ncdf4Convert(). Alternatively, you can call this function in a loop or
using the lapply family of functions.
Keep in mind this function is intended for internal use (or advanced users); it is
exported for convenience. Using the method ncdf4Convert() is recommended.
A string. The path to the converted file or invisible.
The structure of the NetCDF format 4 is straightforward and the variables and attributes are self-evident. The following variables are defined.
retention_time is a vector representing the retention time in seconds (double).
retention_index is a vector representing the retention time indices (double).
If missing, then the variable contains zeros. Its length is equal to the length
of retention_time.
mass_range is vector of length two containing the minimum and maximum m/z
values (integer).
intensity is matrix of intensity values (integer) where columns represent
ion traces and rows are scans. The dimensions are length of "retention time"
times the number of ions, i.e., mass max - mass min + 1.
In addition, the following attributes are defined. Note that only creator and
version are mandatory.
creator a string equal to "TargetSearch" (for identification purposes).
version file format version (string). Currently "1.1".
time_corrected (optional) a flag (short integer) to indicate RI correction.
If missing it defaults to false.
baseline_corrected (optional) a flag (short integer) to indicate that the file was
baseline corrected by TargetSearch. If missing it defaults to false.
Currently, it is not possible to reconstruct the original NetCDF file from the converted file, especially if nominal mass or baseline correction was applied. On the other hand, if the NetCDF files are exported from custom chromatogram files (such as thermo raw files or LECO peg files), then the NetCDF 3 files can be deleted safely as there is always a way to recover them.
Alvaro Cuadros-Inostroza
ncdf4Convert(), ncdf4_convert_from_path(), baseline()
require(TargetSearchData) # get files from package TargetSearchData cdfpath <- tsd_data_path() # choose any file cdf <- file.path(cdfpath, '7235eg04.cdf') nc4 <- '7235eg04.nc4' # save file in current path # run the function ret <- ncdf4_convert(cdf, nc4) # the output should match the output file stopifnot(ret == nc4) # Use mapply to convert many files at the same time. cdf <- paste0('7235eg0', 6:8, '.cdf') nc4 <- paste0('7235eg0', 6:8, '.nc4') ret <- mapply(ncdf4_convert, file.path(cdfpath, cdf), nc4) stopifnot(ret == nc4)require(TargetSearchData) # get files from package TargetSearchData cdfpath <- tsd_data_path() # choose any file cdf <- file.path(cdfpath, '7235eg04.cdf') nc4 <- '7235eg04.nc4' # save file in current path # run the function ret <- ncdf4_convert(cdf, nc4) # the output should match the output file stopifnot(ret == nc4) # Use mapply to convert many files at the same time. cdf <- paste0('7235eg0', 6:8, '.cdf') nc4 <- paste0('7235eg0', 6:8, '.nc4') ret <- mapply(ncdf4_convert, file.path(cdfpath, cdf), nc4) stopifnot(ret == nc4)
Scan and convert NetCDF format 3 files into a custom TargetSearch NetCDF format 4
automatically. The function scans the given input path(s) for files with "cdf" extension.
This function simply wraps around ncdf4_convert(), so that function
will then convert each detected file.
ncdf4_convert_from_path(cdf_path = ".", out_path = cdf_path, recursive = FALSE, ignore.case = TRUE, ...)ncdf4_convert_from_path(cdf_path = ".", out_path = cdf_path, recursive = FALSE, ignore.case = TRUE, ...)
cdf_path |
Character string. The path(s) to scan for CDF files. |
out_path |
Character string. The output path(s) in which the converted files will be saved. |
recursive |
Logical. Should the search recurse into directories? |
ignore.case |
Logical. Should the file extension matching be case insensitive? |
... |
Extra options passed to |
This function simply searches for CDF-3 files and converts them to CDF-4 (custom format). By default the current path is scanned and files are converted and save in the same place.
Multiple input directories can be given. If this is the case, the output path out_path must
be either a single path (in which case all files will be copied to the same directory) or an equal
number of paths, such that there is a corresponding match between input and output directories.
If not, an assertion error will be raised.
By default the search is case insensitive (see parameter ignore.case). For sensitive
case matching, the function looks for all lowercase extension cdf. At the moment,
it is not possible to change this pattern.
If recursive is TRUE, the search will also descend into subdirectories and
the converted files will follow a similar directory structure. Output directories will be
created on demand if required (this is actually done by ncdf4_convert()
internally).
A character vector of generated files or invisible.
Alvaro Cuadros-Inostroza
# in this example we'll use a temporary directory as source # and storage of CDF (because we need to reduce testing time in Bioc) # get some files from package TargetSearchData and copy them # to `srcdir` require(TargetSearchData) cdffiles <- tsd_cdffiles()[1:4] srcdir <- file.path(tempdir(), 'gc-ms-data') dir.create(srcdir) file.copy(cdffiles, srcdir) # convert to output directory set above outdir <- tempfile() ncdf4_convert_from_path(srcdir, outdir) # recursive search. note that output files will be saved under "gc-ms-data" # in the output directory cdfpath <- tempdir() # (base path where we copy the CDF files) ncdf4_convert_from_path(cdfpath, outdir, recursive=TRUE) # clean-up the mess unlink(c(srcdir, outdir), recursive=TRUE)# in this example we'll use a temporary directory as source # and storage of CDF (because we need to reduce testing time in Bioc) # get some files from package TargetSearchData and copy them # to `srcdir` require(TargetSearchData) cdffiles <- tsd_cdffiles()[1:4] srcdir <- file.path(tempdir(), 'gc-ms-data') dir.create(srcdir) file.copy(cdffiles, srcdir) # convert to output directory set above outdir <- tempfile() ncdf4_convert_from_path(srcdir, outdir) # recursive search. note that output files will be saved under "gc-ms-data" # in the output directory cdfpath <- tempdir() # (base path where we copy the CDF files) ncdf4_convert_from_path(cdfpath, outdir, recursive=TRUE) # clean-up the mess unlink(c(srcdir, outdir), recursive=TRUE)
A flexible and convenient function to extract raw data from a NetCDF file format
4 using time ranges and m/z ranges or values. This is a better (and faster)
alternative to the old peakCDFextraction() function, which reads the whole CDF
into memory, specially when only sections of the CDF are needed.
ncdf4_data_extract(cdfFile, massValues, timeRange, useRT = FALSE)ncdf4_data_extract(cdfFile, massValues, timeRange, useRT = FALSE)
cdfFile |
A path to a NetCDF file format 4. |
massValues |
A numeric vector representing m/z values. |
timeRange |
A numeric vector of length 2 representing the lower and upper time limits. |
useRT |
Logical. If |
The function takes a NetCDF format 4 generated by "TargetSearch" and extracts raw intensity values from given m/z ion traces within a given time range. The time range can be in seconds or arbitrary retention time index units. For the latter case, the function expects a time corrected CDF file.
If the given time range is out of range, a NULL value will be returned. In contrast,
if the m/z values are out of range, then zeros will be returned for out of range masses
(provided that the time range is not out of range). If timeRange is missing, then
the whole time range. Similarly, if massRange is missing, then all the masses are
extracted. If both are missing, the function behaves as peakCDFextraction(), but
the output (a named list) uses slightly different names.
The NetCDF must be have been previously converted to the custom "TargetSearch" format,
otherwise an error will be raised. See ncdf4_convert() for the conversion.
A named list with the following components.
Time Numeric vector: the retention time in seconds
Index Numeric vector: the retention time index (or zero if the file was
was not retention time corrected
Intensity Matrix: Rows are the retention times (or scans) and columns are masses.
massRange Numeric vector of length 2: the mass range of the CDF
An error will be produced for invalid files. Also, this function is intended to be used internally, but it is exposed for convenience, for example, to create custom plots.
Alvaro Cuadros-Inostroza
ncdf4_convert(), peakCDFextraction()
# If you already have a NCDF4 file set the variable accordingly # and skip the following section # nc4file <- "/path/to/netcdf4.nc4" ### create NCDF4 from NCDF3 from the package TargetSearchData require(TargetSearchData) # pick first file cdffile <- tsd_cdffiles()[1] nc4file <- tempfile(fileext=".nc4") ncdf4_convert(cdffile, nc4file) # update RI data using pre-computed values ncdf4_update_ri(nc4file, c(252, 311, 269), c(262320, 323120, 381020)) ### end # extract all data (behaves like peakCDFextraction) data <- ncdf4_data_extract(nc4file) # extract only certain m/z values data <- ncdf4_data_extract(nc4file, massValues=c(116, 192)) # to use mass ranges, use the colon (:) operator for example data <- ncdf4_data_extract(nc4file, massValues=c(120:130, 200, 203:209)) # restrict extraction to a retention index interval data <- ncdf4_data_extract(nc4file, massValues=c(116, 192), timeRange=c(200000, 220000)) # same, but using retention time in seconds. data <- ncdf4_data_extract(nc4file, massValues=c(116, 192), timeRange=c(200, 300), useRT=TRUE)# If you already have a NCDF4 file set the variable accordingly # and skip the following section # nc4file <- "/path/to/netcdf4.nc4" ### create NCDF4 from NCDF3 from the package TargetSearchData require(TargetSearchData) # pick first file cdffile <- tsd_cdffiles()[1] nc4file <- tempfile(fileext=".nc4") ncdf4_convert(cdffile, nc4file) # update RI data using pre-computed values ncdf4_update_ri(nc4file, c(252, 311, 269), c(262320, 323120, 381020)) ### end # extract all data (behaves like peakCDFextraction) data <- ncdf4_data_extract(nc4file) # extract only certain m/z values data <- ncdf4_data_extract(nc4file, massValues=c(116, 192)) # to use mass ranges, use the colon (:) operator for example data <- ncdf4_data_extract(nc4file, massValues=c(120:130, 200, 203:209)) # restrict extraction to a retention index interval data <- ncdf4_data_extract(nc4file, massValues=c(116, 192), timeRange=c(200000, 220000)) # same, but using retention time in seconds. data <- ncdf4_data_extract(nc4file, massValues=c(116, 192), timeRange=c(200, 300), useRT=TRUE)
A simple function to plot m/z ion traces from a CDF-4 file. This new interface supersedes
the function plotPeakSimple (but that can be used for CDF-3 files).
ncdf4_plot_peak(obj, massValues, timeRange, useRT = TRUE, showRT = useRT, plot = TRUE, ...)ncdf4_plot_peak(obj, massValues, timeRange, useRT = TRUE, showRT = useRT, plot = TRUE, ...)
obj |
Either a |
massValues |
A numeric vector representing m/z values. |
timeRange |
A numeric vector of length 2 representing the lower and upper time limits. |
useRT |
Logical. If |
showRT |
Logical. Whether the x-axis of the resulting plot should represent seconds
( |
plot |
Logical. If |
... |
Extra arguments, such as |
The function takes a list of path to CDF-4 files or an object of class tsSample
as input; a list a m/z values to select for; and a time range, which can be in seconds
(default) or retention time index (RI) units. For the RI units to work, the CDF files must
have been previously time corrected (See RIcorrect, updateRI).
The selection of the time range units depends on the parameter useRT. If TRUE,
then the search will be restricted to the specified range in seconds, otherwise RI units
will be used. However, the displayed time units are defined by the parameter showRT.
The default behavior is to use the same time units that were search for, but using seconds to
search and RI units to display is possible by setting showRT = !useRT (or the reverse).
This is useful if the retention time correction was not performed correctly and you want
to verify what retention time correspond to what retention index.
The logical parameter plot controls whether a plot is drawn. This might be useful
for simply extracting the data used for the plot and not caring about the plot itself. The function
ncdf4_data_extract can be used for that purpose as well (in fact that function
is run under the hood).
Plot styling can be achieved by passing plotting extra parameters such as col, pch,
lty, and others (see par and plot).
There is however a caveat due to how this function is implemented: the function calls
matlines once per each file (or sample), so parameters
such as col, lty, etc., apply only to the m/z values, not to the samples.
If you want to display different color lines for different samples (for example), add a ‘s’
to the respective parameter name as a prefix. Currently, these parameters are allowed:
scol, stype, slty, slwd, spch, sbg, scex.
See the examples below for details.
Finally, all plotting parameters are cycled over and in case of conflicts, the ‘s’ parameters take precedence.
Either a named list, one element per sample or CDF file, or invisible.
Each element is in itself a list with the following components (same as the output of
ncdf4_data_extract).
Time Numeric vector: the retention time in seconds
Index Numeric vector: the retention time index (or zero if the file was
was not retention time corrected
Intensity Matrix: Rows are the retention times (or scans) and columns are masses.
massRange Numeric vector of length 2: the mass range of the CDF
This function is only for CDF-4 files. Use the method ncdf4Convert or the function
ncdf4_convert for conversion of CDF-3 files. You may also use function
plotPeakSimple if you don't want to convert the files.
Not all graphical parameters passed by ... will work, in particular
panel.first and panel.last are known to not work.
Therefore, for more personalized plots, it is recommended to set plot=FALSE
and use the returned data for plotting.
Alvaro Cuadros-Inostroza
plotPeak,
plotPeakSimple,
ncdf4_data_extract,
RIcorrect,
updateRI
require(TargetSearchData) # load CDF files, convert them and save them in a temporary directory dest <- tempdir() cdf <- tsd_cdffiles()[1:3] cdf <- sapply(cdf, function(x) ncdf4_convert(x, outFile=file.path(dest, basename(x)))) # plot single m/z on many cdf files ncdf4_plot_peak(cdf, massValues=c(144), timeRange=c(255, 265)) # add some style (note the usage of `slty` and `scol`) ncdf4_plot_peak(cdf, massValues=c(144), timeRange=c(255, 265), scol=1:3, slty=1:3, main='Example Plot') # plot many m/z on single cdf file (colors are set by matlines) ncdf4_plot_peak(cdf[1], massValues=c(144, 145, 100, 218), timeRange=c(255, 265)) # add some styling (here simply use `lty` and `col`) ncdf4_plot_peak(cdf[1], massValues=c(144, 145, 100, 218), timeRange=c(255, 265), col=1:4, lty=1, main='Example Plot') # multiple m/z and files is possible but it gets messy ncdf4_plot_peak(cdf, massValues=c(144, 145, 218), timeRange=c(255, 265), scol=1:3, main='Example Plot') # do not plot anything and just get the data z <- ncdf4_plot_peak(cdf, massValues=c(144, 145, 218), timeRange=c(255, 265), plot=FALSE) str(z) # using a tsSample object can achieve the same results smp <- ImportSamplesFromDir(dest) ncdf4_plot_peak(smp, massValues=c(144), timeRange=c(255, 265))require(TargetSearchData) # load CDF files, convert them and save them in a temporary directory dest <- tempdir() cdf <- tsd_cdffiles()[1:3] cdf <- sapply(cdf, function(x) ncdf4_convert(x, outFile=file.path(dest, basename(x)))) # plot single m/z on many cdf files ncdf4_plot_peak(cdf, massValues=c(144), timeRange=c(255, 265)) # add some style (note the usage of `slty` and `scol`) ncdf4_plot_peak(cdf, massValues=c(144), timeRange=c(255, 265), scol=1:3, slty=1:3, main='Example Plot') # plot many m/z on single cdf file (colors are set by matlines) ncdf4_plot_peak(cdf[1], massValues=c(144, 145, 100, 218), timeRange=c(255, 265)) # add some styling (here simply use `lty` and `col`) ncdf4_plot_peak(cdf[1], massValues=c(144, 145, 100, 218), timeRange=c(255, 265), col=1:4, lty=1, main='Example Plot') # multiple m/z and files is possible but it gets messy ncdf4_plot_peak(cdf, massValues=c(144, 145, 218), timeRange=c(255, 265), scol=1:3, main='Example Plot') # do not plot anything and just get the data z <- ncdf4_plot_peak(cdf, massValues=c(144, 145, 218), timeRange=c(255, 265), plot=FALSE) str(z) # using a tsSample object can achieve the same results smp <- ImportSamplesFromDir(dest) ncdf4_plot_peak(smp, massValues=c(144), timeRange=c(255, 265))
Performs retention time index (RI) correction on a CDF file, using the
retention markers found by RIcorrect(), or to force the markers time
if, for example, the RI markers were not co-injected with the biological
samples. It wraps around rt2ri()
ncdf4_update_ri(cdfFile, observed, standard)ncdf4_update_ri(cdfFile, observed, standard)
cdfFile |
Path to the CDF file |
observed |
The observed RI markers retention times'. |
standard |
The RI of said markers. |
This function is similar to fixRI(), with the difference that is acts
upon a single file, whereas fixRI() requires a tsSample
object.
Returns invisible
This function is meant to be used internally. It is exposed for convenience.
Alvaro Cuadros-Inostroza
fixRI, RIcorrect, ImportFameSettings
# pull a CDF file from package TargetSearchData as example require(TargetSearchData) cdffile <- tsd_cdffiles()[9] # we need to convert from NCDF3 to NCDF4 in this example # (NCDF3 files do not work) nc4file <- ncdf4_convert(cdffile, 'example.nc4') # to update the RI we need to pass two equal-length vectors of # observed RT and standard RI values. obsRT <- c(252, 311, 369) # approx time of RI markers stdRI <- c(262320, 323120, 381020) # the exact RI of the markers # finally update the RI for these file ncdf4_update_ri(nc4file, obsRT, stdRI)# pull a CDF file from package TargetSearchData as example require(TargetSearchData) cdffile <- tsd_cdffiles()[9] # we need to convert from NCDF3 to NCDF4 in this example # (NCDF3 files do not work) nc4file <- ncdf4_convert(cdffile, 'example.nc4') # to update the RI we need to pass two equal-length vectors of # observed RT and standard RI values. obsRT <- c(252, 311, 369) # approx time of RI markers stdRI <- c(262320, 323120, 381020) # the exact RI of the markers # finally update the RI for these file ncdf4_update_ri(nc4file, obsRT, stdRI)
ncdf4Convert is a high level method used to convert from
CDF-3 to ‘TargetSearch’ new CDF-4 custom file format.
ncdf4Convert(obj, path, ...)ncdf4Convert(obj, path, ...)
obj |
A |
path |
A character vector representing file path in which the newly created CDF-4 files will be stored. If missing, the files will be save in the same directory as the source CDF-3 files |
... |
Extra arguments passed to |
This is a high level interface to ncdf4_convert which
uses a tsSample as input. The advantage of using
this function is that it updates the paths to the CDF-4 files for
downstream analysis.
The parameter path can be used to change the original paths,
which may be necessary if those files are on a read-only file-system.
If this parameter is missing, the same paths are used. Note that
the path are re-cycled to match the length of the samples.
The ... can be used to pass extra arguments to ncdf4_convert
and to baseline. Refer to those man pages for details.
A new tsSample object with updated CDF-4 file paths.
The files are converted in the background.
Alvaro Cuadros-Inostroza
require(TargetSearchData) data(TSExample) # get the CDF files cdfpath <- tsd_data_path() # update the CDF path CDFpath(sampleDescription) <- cdfpath # transform the CDF (the files are copied in the current directoru) newSamples <- ncdf4Convert(sampleDescription, path=".")require(TargetSearchData) data(TSExample) # get the CDF files cdfpath <- tsd_data_path() # update the CDF path CDFpath(sampleDescription) <- cdfpath # transform the CDF (the files are copied in the current directoru) newSamples <- ncdf4Convert(sampleDescription, path=".")
This function reads a netcdf chromatogram file, finds the apex intensities and returns a list containing the retention time and the intensity matrices.
NetCDFPeakFinding(ncdf, massRange = NULL, Window = 15, IntThreshold = 10, pp.method = "ppc", baseline = FALSE, ...)NetCDFPeakFinding(ncdf, massRange = NULL, Window = 15, IntThreshold = 10, pp.method = "ppc", baseline = FALSE, ...)
ncdf |
A character string naming a netcdf file or a list generated by the function
|
massRange |
Deprecated. It is completely ignored but it is kept for compatibility with old scripts. |
Window |
The window used by peak picking method. The number of points actually used
is |
IntThreshold |
Apex intensities lower than this value will be removed from the RI files. |
pp.method |
The pick picking method to be used. Options are |
baseline |
Logical. Should baseline correction be performed? |
... |
Extra options passed to |
The parameter ncdf should be either a path to a NetCDF file or a list
generated by the function peakCDFextraction. This list contains elements
named "Time", "Peaks", "massRange", "Index", and "baselineCorrected". Refer to
the function's man page for details.
Formerly, the massRange parameter was a numeric vector with two components: lower
and higher masses. Now, the mass range is detected automatically and it has no effect if
it is set. It is kept only for compatibility reasons.
There are three peak picking algorithms that can be used. The "smoothing" method
smooths the m/z curves by a moving average and then looks for a change of sign of the
intensity difference between two consecutive points. The "gaussian" is exactly
the same, but it uses a gaussian smoother instead of a moving average.
The "ppc" uses a sliding window and looks for the local maxima. This method is
based on the R-package ppc (now unavailable).
A three component list.
Time |
The retention time vector. |
Peaks |
The intensity matrix. Rows are the retention times and columns are masses. The first column is the lower mass value and the last one is the higher mass. |
massRange |
The mass range. |
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
require(TargetSearchData) # pick first CDF file CDFfile <- tsd_cdffiles()[1] # extract peaks of first chromatogram peaks.1 <- NetCDFPeakFinding(CDFfile, Window = 15, IntThreshold = 10, pp.method = "ppc") # scan acquisition times head(peaks.1$Time) # peaks in matrix form. first column is mass 85, last one is mass 320. head(peaks.1$Peaks)require(TargetSearchData) # pick first CDF file CDFfile <- tsd_cdffiles()[1] # extract peaks of first chromatogram peaks.1 <- NetCDFPeakFinding(CDFfile, Window = 15, IntThreshold = 10, pp.method = "ppc") # scan acquisition times head(peaks.1$Time) # peaks in matrix form. first column is mass 85, last one is mass 320. head(peaks.1$Peaks)
This function reads a netcdf chromatogram (format 3 or 4) file and returns a list containing raw data (retention time, intensity matrix) for easy manipulation.
peakCDFextraction(cdfFile, massRange)peakCDFextraction(cdfFile, massRange)
cdfFile |
A character string naming a netcdf file. |
massRange |
Deprecated. The mass range is extracted automatically. |
The cdfFile is a path to a CDF-3 or a CDF-4 format file. The CDF-4
format file is a custom file used on TargetSearch.
The massRange parameter is deprecated but kept for compatibility.
The actual m/z range is detected automatically and returned to the user.
A list with the following components:
Time |
The retention time vector. |
Index |
The retention time index vector or NULL if unavailable. |
Peaks |
The intensity matrix. Rows are the retention times and columns are masses. The first column is the lower mass value and the last one is the higher mass. |
massRange |
The mass range. |
baselineCorrected |
Logical. It is |
This function does not look for peaks, just extracts all the raw intensity values
of the chromatogram file. Use NetCDFPeakFinding instead.
The function does not know whether a CDF file was baseline corrected (for
example by the GC-MS software vendor), unless it was performed by the
function baseline. It is perfectly possible to have a
baseline corrected file and the element baselineCorrected be FALSE.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
ncdf4_data_extract for an updated and more flexible version
of this function, NetCDFPeakFinding, baseline.
### take a NCDF3 file from the package TargetSearchData require(TargetSearchData) # pick a CDF file and extract its data cdffile <- tsd_cdffiles()[4] peakData <- peakCDFextraction(cdffile) # it also works for NCDF4 files (we need to convert the file first) nc4file <- ncdf4_convert(cdffile, tempfile(fileext='.nc4')) peakData2 <- peakCDFextraction(nc4file) # clean-up unlink(nc4file)### take a NCDF3 file from the package TargetSearchData require(TargetSearchData) # pick a CDF file and extract its data cdffile <- tsd_cdffiles()[4] peakData <- peakCDFextraction(cdffile) # it also works for NCDF4 files (we need to convert the file first) nc4file <- ncdf4_convert(cdffile, tempfile(fileext='.nc4')) peakData2 <- peakCDFextraction(nc4file) # clean-up unlink(nc4file)
This function returns a list of the intensities and RI matrices that were searched.
peakFind(samples, Lib, cor_RI, columns = NULL, showProgressBar = FALSE)peakFind(samples, Lib, cor_RI, columns = NULL, showProgressBar = FALSE)
samples |
A |
Lib |
A |
cor_RI |
A matrix of correlating selective masses RI for every sample.
See |
columns |
Either |
showProgressBar |
Logical. Should the progress bar be displayed? |
A tsMSdata object.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
ImportSamples, ImportLibrary, medianRILib,
sampleRI, tsMSdata, tsLib,
tsSample
require(TargetSearchData) data(TSExample) # get RI file path RI.path <- tsd_data_path() refLibrary <- ImportLibrary(tsd_file_path("library.txt")) # update RI file path RIpath(sampleDescription) <- RI.path peakData <- peakFind(sampleDescription, refLibrary, corRI) # show peak Intensities. head(Intensity(peakData), 2) # How to get intensities for a particular metabolite # just select the identifier. Here extract the intensities # for the first metabolite in the library IntMatrix <- Intensity(peakData)[[1]]require(TargetSearchData) data(TSExample) # get RI file path RI.path <- tsd_data_path() refLibrary <- ImportLibrary(tsd_file_path("library.txt")) # update RI file path RIpath(sampleDescription) <- RI.path peakData <- peakFind(sampleDescription, refLibrary, corRI) # show peak Intensities. head(Intensity(peakData), 2) # How to get intensities for a particular metabolite # just select the identifier. Here extract the intensities # for the first metabolite in the library IntMatrix <- Intensity(peakData)[[1]]
Plots a given standard marker.
plotFAME(samples, RImatrix, whichFAME)plotFAME(samples, RImatrix, whichFAME)
samples |
A |
RImatrix |
A retention time matrix of the found retention time markers. |
whichFAME |
The retention marker to plot. Must be a number between |
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
RIcorrect, FAMEoutliers,
tsSample
data(TSExample) # plot Retention index standards 1 to 3 plotFAME(sampleDescription, RImatrix, 1) plotFAME(sampleDescription, RImatrix, 2) plotFAME(sampleDescription, RImatrix, 3)data(TSExample) # plot Retention index standards 1 to 3 plotFAME(sampleDescription, RImatrix, 1) plotFAME(sampleDescription, RImatrix, 2) plotFAME(sampleDescription, RImatrix, 3)
Plot a peak of a given metabolite in a given sample showing the search windows.
plotPeak(samples, Lib, metProf, rawpeaks, which.smp=1, which.met=1, massRange=NULL, corMass=FALSE)plotPeak(samples, Lib, metProf, rawpeaks, which.smp=1, which.met=1, massRange=NULL, corMass=FALSE)
samples |
A |
Lib |
A |
metProf |
A metabolite profile object. See |
rawpeaks |
A three component list containing the retention time, the intensity matrix,
and the mass range. See |
which.smp |
A numeric value indicating the sample. |
which.met |
A numeric value indicating the metabolite. |
massRange |
A two component numeric vector with the scan mass range to extract.
Use |
corMass |
Logical. If TRUE, show only correlating masses for the selected metabolite. Show all masses otherwise. |
The output is the same as the function peakCDFextraction, that is, a list
containing the retention time (Time), the intensity matrix (Peaks),
the retention index (Index), the m/z range (massRange), and a flag indicating
whether the chromatogram was baseline corrected (baselineCorrected).
The list can be recycled as the rawpeaks parameter for further plots (for example
in a loop), so the CDF file doesn't need to be read again.
This function was completely rewritten. For the old function, see plotPeakSimple.
In case the RI files are in text format and their column names are not standard (for
example, when the files were generated with another software), use the global option
'TS_RI_columns' or transform the RI files to TargetSearch binary
format. See the documentation in function text2bin.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
plotPeakSimple, RIcorrect, tsMSdata, tsRim,
peakCDFextraction, matplot
require(TargetSearchData) data(TSExample) # update CDF and RI paths CDFpath(sampleDescription) <- tsd_data_path() RIpath(sampleDescription) <- tsd_data_path() # Plot the peak "Valine" for sample number 1 grep("Valine", libName(refLibrary)) # answer: 3 # plot peak from the cdf file. The rawpeaks object can be recycled in order to plot # other metabolites. rawpeaks <- plotPeak(sampleDescription, refLibrary, metabProfile, which.smp=1, which.met=3, massRange=c(85,500), corMass=FALSE)require(TargetSearchData) data(TSExample) # update CDF and RI paths CDFpath(sampleDescription) <- tsd_data_path() RIpath(sampleDescription) <- tsd_data_path() # Plot the peak "Valine" for sample number 1 grep("Valine", libName(refLibrary)) # answer: 3 # plot peak from the cdf file. The rawpeaks object can be recycled in order to plot # other metabolites. rawpeaks <- plotPeak(sampleDescription, refLibrary, metabProfile, which.smp=1, which.met=3, massRange=c(85,500), corMass=FALSE)
Plot peak RI of the quant mass of a given metabolite across samples.
This function can be used to visualize the elution time of a metabolite
in the RI and RT dimension, and in combination with the function
sampleRI for fine tuning.
plotPeakRI(samples, Lib, libID, dev=NULL, mz=NULL, RI=NULL, RT=NULL, method=c('RI', 'Intensity'), useRI=TRUE, main=NULL, col=NULL, int_range=c(2,6), cex_range=c(.7,6), key_width=2)plotPeakRI(samples, Lib, libID, dev=NULL, mz=NULL, RI=NULL, RT=NULL, method=c('RI', 'Intensity'), useRI=TRUE, main=NULL, col=NULL, int_range=c(2,6), cex_range=c(.7,6), key_width=2)
samples |
A |
Lib |
A |
libID |
An index (integer or character) value representing the respective metabolite in
the reference library |
dev |
The allowed retention index (RI) deviation or |
mz |
A list of m/z values to search or |
RI |
The expected retention index or |
RT |
The expected retention time to search for instead of retention index, or |
method |
A character vector used to decided what peak should be chosen in case there are
ambiguous peaks. If |
useRI |
Logical. Should the RI or RT be displayed in the y-axis? |
main |
The title for the plot. If |
col |
A color vector (length > 2) to show different levels of peak intensity. |
int_range |
A length-two vector. The limits of the intensity for the color key. Note that the intensity is expressed in log10, for example, a value of 2 represents an intensity of 100. |
cex_range |
The 'cex' range value of the points. Lower-intense peaks are represented as points of smaller size. |
key_width |
The width in cm of the area allocated for the color key. |
This function uses internally FindAllPeaks, so the same rules apply,
i.e., the parameters dev, mz, RI, and RT have preference over
the settings of the metabolite indexed by libID.
In the plot, the x-axis are samples as defined by the object samples. The
y-axis is retention index (RI) as shown on the left-hand-size. On the right-hand-size
y-axis the approximate retention time (RT) is shown. This is because the RT varies
across samples, therefore it is averaged for displays purposes. If useRI==FALSE,
then the RT is displayed on the left hand size and the RI is averaged and shown on
the left.
Note that in general, the RI of the library or the RI given by the user is used for
peak searching, regardless of the value of parameter useRI. To search for RT
instead, then the parameter RT is required, as well as the deviation parameter
dev, as in the function FindAllPeaks.
The point size is proportional to the log10 of the peak intensity. Their size is
controlled by the parameters int_range and cex_range. By default,
intensities of 100 (log10 => 2) or lower are shown with cex=0.7, while intensities
greater than 1000000 (log10 => 6) as displayed with cex=6. This also affects the
scaling of the color key.
The best peaks, selected according to method, are shown with a black border,
while the other are shown with no border and slightly transparent.
The output is the RI of the best peaks or invisible. Note that if no peak is found, then no plot is drawn.
Returns invisible or a numeric vector with the corresponding RI of the best peak chosen by
method. The RI is returned even when the parameters useRI is set to
TRUE or the parameter RT is specified.
For a more comprehensive output (but less nicer plot), check the function
ri_plot_peak.
Alvaro Cuadros-Inostroza
The function ri_plot_peak which is a low level version
of this function, as well as FindAllPeaks for details of
the peak searching parameters. Check also referenced functions
sampleRI, ImportSamples, and ImportLibrary
def.par <- par(no.readonly = TRUE) # save parameters for resetting # load pre-calculated example data files and objects require(TargetSearchData) data(TSExample) # get and set the RI file path RIpath(sampleDescription) <- tsd_data_path() # search all peaks of Valine (GC.3) and selective masses. Retention index ri <- plotPeakRI(sampleDescription, refLibrary, 'GC.3') # increase deviation, change m/z to search, change colors and title main <- 'Valine' cols <- c('red', 'blue', 'green') ri <- plotPeakRI(sampleDescription, refLibrary, 'GC.3', dev=4000, mz=144, main=main, col=cols) # plot by RT instead. Note the RI is still returned and used for searching ri <- plotPeakRI(sampleDescription, refLibrary, 'GC.3', useRI=FALSE) # same, but search by RT instead of RI. Note that the deviation 'dev' is # required ri2 <- plotPeakRI(sampleDescription, refLibrary, 'GC.3', useRI=FALSE, RT=261, dev=2) stopifnot(ri == ri2) # should be the same par(def.par) # reset to defaultdef.par <- par(no.readonly = TRUE) # save parameters for resetting # load pre-calculated example data files and objects require(TargetSearchData) data(TSExample) # get and set the RI file path RIpath(sampleDescription) <- tsd_data_path() # search all peaks of Valine (GC.3) and selective masses. Retention index ri <- plotPeakRI(sampleDescription, refLibrary, 'GC.3') # increase deviation, change m/z to search, change colors and title main <- 'Valine' cols <- c('red', 'blue', 'green') ri <- plotPeakRI(sampleDescription, refLibrary, 'GC.3', dev=4000, mz=144, main=main, col=cols) # plot by RT instead. Note the RI is still returned and used for searching ri <- plotPeakRI(sampleDescription, refLibrary, 'GC.3', useRI=FALSE) # same, but search by RT instead of RI. Note that the deviation 'dev' is # required ri2 <- plotPeakRI(sampleDescription, refLibrary, 'GC.3', useRI=FALSE, RT=261, dev=2) stopifnot(ri == ri2) # should be the same par(def.par) # reset to default
Plot selected ions in a given time range. This is the old plot peak interface.
Note: This function is considered deprecated and its usage is
discouraged; users should use ncdf4_plot_peak.
plotPeakSimple(rawpeaks, time.range, masses, cdfFile = NULL, useRI = FALSE, rimTime = NULL, standard = NULL, massRange = NULL, ...)plotPeakSimple(rawpeaks, time.range, masses, cdfFile = NULL, useRI = FALSE, rimTime = NULL, standard = NULL, massRange = NULL, ...)
rawpeaks |
A three component list containing the retention time, the intensity matrix,
and the mass range. See |
time.range |
The time range to plot in retention time or retention time index units to plot. |
masses |
A vector containing the ions or masses to plot. |
cdfFile |
The name of a CDF file. If a file name is specified, the ions will be extracted
from there instead of using |
useRI |
Logical. Whether to use Retention Time Indices or not. |
rimTime |
A retention time matrix of the found retention time markers. It is only used
when |
standard |
A numeric vector with RI values of retention time markers. It is only used
when |
massRange |
A two component numeric vector with the scan mass range to extract or
|
... |
Further options passed to |
This function used to be named 'plotPeak'. This function was completely rewritten so we kept the old version and renamed it 'plotPeakSimple'.
Important: This function is considered deprecated, though it is not yet labeled as such.
Please consider using ncdf4_plot_peak. This function, however, needs CDF files
version 4.
That said, this function can still be used to plot peaks for CDF files version 3 without the need to convert them to CDF format 4.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
plotPeak, RIcorrect, tsMSdata, tsRim,
peakCDFextraction, matplot, ncdf4_plot_peak for the new interface.
require(TargetSearchData) data(TSExample) # update CDF path CDFpath(sampleDescription) <- tsd_data_path() # Plot the peak "Valine" for sample number 1 grep("Valine", libName(refLibrary)) # answer: 3 # select the first file cdfFile <- CDFfiles(sampleDescription)[1] # select "Valine" top masses top.masses <- topMass(refLibrary)[[3]] # plot peak from the cdf file plotPeakSimple(cdfFile = cdfFile, time.range = libRI(refLibrary)[3] + c(-2000,2000), masses = top.masses, useRI = TRUE, rimTime = RImatrix[,1], standard = rimStandard(rimLimits), massRange = c(85, 500)) # the same, but extracting the peaks into a list first. This may be better if # you intend to loop through several peaks. rawpeaks <- peakCDFextraction(cdfFile, massRange = c(85,500)) plotPeakSimple(rawpeaks, time.range = libRI(refLibrary)[3] + c(-2000,2000), masses = top.masses, useRI = TRUE, rimTime = RImatrix[,1], standard = rimStandard(rimLimits), massRange = c(85, 500))require(TargetSearchData) data(TSExample) # update CDF path CDFpath(sampleDescription) <- tsd_data_path() # Plot the peak "Valine" for sample number 1 grep("Valine", libName(refLibrary)) # answer: 3 # select the first file cdfFile <- CDFfiles(sampleDescription)[1] # select "Valine" top masses top.masses <- topMass(refLibrary)[[3]] # plot peak from the cdf file plotPeakSimple(cdfFile = cdfFile, time.range = libRI(refLibrary)[3] + c(-2000,2000), masses = top.masses, useRI = TRUE, rimTime = RImatrix[,1], standard = rimStandard(rimLimits), massRange = c(85, 500)) # the same, but extracting the peaks into a list first. This may be better if # you intend to loop through several peaks. rawpeaks <- peakCDFextraction(cdfFile, massRange = c(85,500)) plotPeakSimple(rawpeaks, time.range = libRI(refLibrary)[3] + c(-2000,2000), masses = top.masses, useRI = TRUE, rimTime = RImatrix[,1], standard = rimStandard(rimLimits), massRange = c(85, 500))
A simple function to plot the reference spectrum of a compound in the style of common visualization tools. This is useful when comparing the spectrum of a metabolite with such software tools.
plotRefSpectra(lib, libID, col='darkblue', main=NULL, xlab='m/z', ylab='Intensity', label=TRUE, cex=0.8, label_col=NULL, sel_font=4, type='h', ...)plotRefSpectra(lib, libID, col='darkblue', main=NULL, xlab='m/z', ylab='Intensity', label=TRUE, cex=0.8, label_col=NULL, sel_font=4, type='h', ...)
lib |
A |
libID |
An index (integer or character) value representing the respective metabolite in
the reference library |
col |
The color(s) of the vertical lines. This option is passed to
|
main |
The title for the plot. If |
xlab |
The x axis label. Passed to |
ylab |
The y axis label. Passed to |
label |
Logical. It controls whether the m/z labels are displayed. |
cex |
The |
label_col |
The color vector for the m/z labels. |
sel_font |
The font for the m/z labels of the selective masses. This should
be an integer like the parameter |
type |
A character that specifies the plot type. Defaults to |
... |
Extra graphical parameters passed to |
This is a simple function to plot the spectrum of a reference metabolite. It is expected that the spectrum for that metabolite is not empty, in which case nothing is plotted and a warning is thrown.
The m/z label positions are determined automatically such that they do not intersect with each other and do not touch the vertical lines of the plot.
Returns invisible().
Alvaro Cuadros-Inostroza
See the function ImportLibrary for importing a metabolite library.
See plot and par for graphical parameters.
def.par <- par(no.readonly = TRUE) # save parameters for resetting # load pre-calculated example data files and objects data(TSExample) # plot the reference spectrum of the compound ID 'GC.3' plotRefSpectra(refLibrary, 'GC.3') # that is equivalent to plotRefSpectra(refLibrary['GC.3']) # change some graphical parameter and add a grid via 'panel.first' plotRefSpectra(refLibrary, 'GC.3', col='darkred', main='Valine', xlab='mz', ylab='intensity', cex=0.7, label_col='blue', sel_font=2, panel.first=grid()) par(def.par) # reset to defaultdef.par <- par(no.readonly = TRUE) # save parameters for resetting # load pre-calculated example data files and objects data(TSExample) # plot the reference spectrum of the compound ID 'GC.3' plotRefSpectra(refLibrary, 'GC.3') # that is equivalent to plotRefSpectra(refLibrary['GC.3']) # change some graphical parameter and add a grid via 'panel.first' plotRefSpectra(refLibrary, 'GC.3', col='darkred', main='Valine', xlab='mz', ylab='intensity', cex=0.7, label_col='blue', sel_font=2, panel.first=grid()) par(def.par) # reset to default
plotRIdev plots the Retention Time Index Deviation of a given set of metabolites.
plotAllRIdev saves the plots of the RI deviations of all the metabolites in the library object
into a PDF file.
plotRIdev(Lib, peaks, libID = 1, ...) plotAllRIdev(Lib, peaks, pdfFile, width = 8, height = 8, ...)plotRIdev(Lib, peaks, libID = 1, ...) plotAllRIdev(Lib, peaks, pdfFile, width = 8, height = 8, ...)
Lib |
A |
peaks |
A |
libID |
A numeric vector providing the indices of the metabolites to plot. |
pdfFile |
A file name where the plot will be saved. Only |
width, height
|
The width and height of the plots in inches. Only |
... |
Further options passed to |
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
ImportLibrary, tsLib,
tsMSdata, pdf
require(TargetSearchData) data(TSExample) # get RI file path RI.path <- tsd_data_path() # update RI file path RIpath(sampleDescription) <- RI.path peakData <- peakFind(sampleDescription, refLibrary, corRI) # Plot RI deviation of metabolite "Valine" grep("Valine", libName(refLibrary)) # answer: 3 plotRIdev(refLibrary, peakData, libID = 3) # Plot an RI deviation overview of the first nine metabolites plotRIdev(refLibrary, peakData, libID = 1:9) # Save all RI deviation into a pdf file plotAllRIdev(refLibrary, peakData, pdfFile = "RIdeviations.pdf")require(TargetSearchData) data(TSExample) # get RI file path RI.path <- tsd_data_path() # update RI file path RIpath(sampleDescription) <- RI.path peakData <- peakFind(sampleDescription, refLibrary, corRI) # Plot RI deviation of metabolite "Valine" grep("Valine", libName(refLibrary)) # answer: 3 plotRIdev(refLibrary, peakData, libID = 3) # Plot an RI deviation overview of the first nine metabolites plotRIdev(refLibrary, peakData, libID = 1:9) # Save all RI deviation into a pdf file plotAllRIdev(refLibrary, peakData, pdfFile = "RIdeviations.pdf")
plotSpectra plots a contrast between the reference spectra and the median spectra of a
given metabolite in the library. plotAllRIdev saves the plots of the median-reference
spectra comparisons of all the metabolites in the reference library into a PDF file.
plotSpectra(Lib, peaks, libID = 1, type = c("ht", "ss", "diff")) plotAllSpectra(Lib, peaks, type = "ht", pdfFile, width = 8, height = 8, ...)plotSpectra(Lib, peaks, libID = 1, type = c("ht", "ss", "diff")) plotAllSpectra(Lib, peaks, type = "ht", pdfFile, width = 8, height = 8, ...)
Lib |
A |
peaks |
A |
libID |
A numeric vector providing the indices of the metabolites to plot. |
type |
The type of the plot. Options are |
pdfFile |
A file name where the plot will be saved. Only |
width, height
|
The width and height of the plots in inches. Only |
... |
Further options passed to |
The median spectra is obtained by computing the median intensity of every ion across the samples. The median and the reference spectra values are scaled to vary between 0 and 999 in order to make them comparable.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
require(TargetSearchData) data(TSExample) # get RI file path RI.path <- tsd_data_path() # update RI file path RIpath(sampleDescription) <- RI.path peakData <- peakFind(sampleDescription, refLibrary, corRI) # Plot a comparison RI deviation of metabolite "Valine" grep("Valine", libName(refLibrary)) # answer: 3 plotSpectra(refLibrary, peakData, libID = 3, type = "ht") # Plot the spectra "side by side" plotSpectra(refLibrary, peakData, libID = 3, type = "ss") # Plot the spectra difference plotSpectra(refLibrary, peakData, libID = 3, type = "diff")require(TargetSearchData) data(TSExample) # get RI file path RI.path <- tsd_data_path() # update RI file path RIpath(sampleDescription) <- RI.path peakData <- peakFind(sampleDescription, refLibrary, corRI) # Plot a comparison RI deviation of metabolite "Valine" grep("Valine", libName(refLibrary)) # answer: 3 plotSpectra(refLibrary, peakData, libID = 3, type = "ht") # Plot the spectra "side by side" plotSpectra(refLibrary, peakData, libID = 3, type = "ss") # Plot the spectra difference plotSpectra(refLibrary, peakData, libID = 3, type = "diff")
This function makes a profile from the masses that correlate for each metabolite.
Profile(samples, Lib, peakData, r_thres = 0.95, method = "dayNorm", minPairObs = 5)Profile(samples, Lib, peakData, r_thres = 0.95, method = "dayNorm", minPairObs = 5)
samples |
A |
Lib |
A |
peakData |
A |
r_thres |
A correlation threshold. |
method |
Normalisation method. Options are |
minPairObs |
Minimum number of pair observations. Correlations between two variables are computed using all complete pairs of observations in those variables. If the number of observations is too small, you may get high correlations values just by chance, so this parameters is used to avoid that. Cannot be set lower than 5. |
A tsProfile object. The slots are:
Info |
A data frame with a profile of all masses that correlate. |
Intensity |
A list containing peak-intensity matrices, one matrix per metabolite. |
RI |
A list containing RI matrices, one matrix per metabolite. |
profInt |
A matrix with the averaged intensities of the correlating masses. |
profRI |
A matrix with the averaged RI of the correlating masses. |
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
ImportSamples, ImportLibrary, medianRILib,
peakFind, tsProfile
require(TargetSearchData) data(TSExample) # get RI file path RI.path <- tsd_data_path() # update RI file path RIpath(sampleDescription) <- RI.path # Import Library refLibrary <- ImportLibrary(tsd_file_path('library.txt')) # update median RI refLibrary <- medianRILib(sampleDescription, refLibrary) # get the sample RI corRI <- sampleRI(sampleDescription, refLibrary, r_thres = 0.95) # obtain the peak Intensities of all the masses in the library peakData <- peakFind(sampleDescription, refLibrary, corRI) # make a profile of the metabolite data metabProfile <- Profile(sampleDescription, refLibrary, peakData, r_thres = 0.95) # same as above, but with different thresholds. metabProfile <- Profile(sampleDescription, refLibrary, peakData, r_thres = 0.9, minPairObs = 5)require(TargetSearchData) data(TSExample) # get RI file path RI.path <- tsd_data_path() # update RI file path RIpath(sampleDescription) <- RI.path # Import Library refLibrary <- ImportLibrary(tsd_file_path('library.txt')) # update median RI refLibrary <- medianRILib(sampleDescription, refLibrary) # get the sample RI corRI <- sampleRI(sampleDescription, refLibrary, r_thres = 0.95) # obtain the peak Intensities of all the masses in the library peakData <- peakFind(sampleDescription, refLibrary, corRI) # make a profile of the metabolite data metabProfile <- Profile(sampleDescription, refLibrary, peakData, r_thres = 0.95) # same as above, but with different thresholds. metabProfile <- Profile(sampleDescription, refLibrary, peakData, r_thres = 0.9, minPairObs = 5)
This function reduces/removes redundancy in a profile.
ProfileCleanUp(Profile, timeSplit=500, r_thres=0.95, minPairObs=5, prioritization=c('mass','score'), corMass=1, score=0, show=c('unidentified','knowns','full'))ProfileCleanUp(Profile, timeSplit=500, r_thres=0.95, minPairObs=5, prioritization=c('mass','score'), corMass=1, score=0, show=c('unidentified','knowns','full'))
Profile |
A |
timeSplit |
A RI window. |
r_thres |
A correlation threshold. |
minPairObs |
Minimum number of pair observations. Correlations between two variables are computed using all complete pairs of observations in those variables. If the number of observations is too small, you may get high correlations values just by chance, so this parameters is used to avoid that. Cannot be set lower than 5. |
prioritization |
Selects whether the metabolite suggestion should be based on
the number of correlation masses ( |
corMass |
Metabolites with a number of correlation masses lower than |
score |
Metabolites with a score lower than |
show |
A character vector. If |
Metabolites that are inside a timeSplit window will be correlated
to see whether the metabolites are potentially the same or not, by using
r_thres as a cutoff. If so, the best candidate will be chosen
according to the value of prioritization: If 'mass', then
metabolites will be suggested based on number of correlating masses, and
if 'score', then the score will be used. Metabolites that don't have
al least corMass correlating masses and score score will
be marked as 'unidentified' and not will be suggested, unless all the
metabolites in group are unidentified.
For example, suppose that three metabolites A (CM=3, S=900), B (CM=6, S=700), C (CM=5, S=800) correlate within the same time group, where CM is the number of correlating masses and S is the score.
If prioritization='mass', corMass=3, score=650, then the suggested order is B, C, A.
If prioritization='mass', corMass=3, score=750, then the suggested order is C, A, B.
If prioritization='mass', corMass=3, score=850, then the suggested order is A, B, C.
If prioritization='score', corMass=3, score=650, then the suggested order is A, C, B.
If prioritization='score', corMass=4, score=650, then the suggested order is C, B, A.
If prioritization='score', corMass=4, score=850, then the suggested order is C, A, B.
Note that by choosing prioritization='mass', score=0, and
corMass=1 you will get the former behavior (TargetSearch <= 1.6).
A tsProfile object with a non-redundant profile of the masses that
were searched and correlated, and intensity and RI matrices of the correlating masses.
slot "Info" |
A data frame with a profile of all masses that correlate and the metabolites
that correlate in a |
slot "profInt" |
A matrix with the averaged intensities of the correlating masses. |
slot "profRI" |
A matrix with the averaged RI of the correlating masses. |
slot "Intensity" |
A list containing peak-intensity matrices, one matrix per metabolite. |
slot "RI" |
A list containing RI matrices, one matrix per metabolite. |
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
# load example data require(TargetSearchData) data(TSExample) RI.path <- tsd_data_path() refLibrary <- ImportLibrary(tsd_file_path("library.txt")) # update RI file path RIpath(sampleDescription) <- RI.path # Import Library refLibrary <- ImportLibrary(tsd_file_path('library.txt')) # update median RI refLibrary <- medianRILib(sampleDescription, refLibrary) # get the sample RI corRI <- sampleRI(sampleDescription, refLibrary, r_thres = 0.95) # obtain the peak Intensities of all the masses in the library peakData <- peakFind(sampleDescription, refLibrary, corRI) metabProfile <- Profile(sampleDescription, refLibrary, peakData, r_thres = 0.95) # here we use the metabProfile previously calculated and return a "cleaned" profile. metabProfile.clean <- ProfileCleanUp(metabProfile, timeSplit = 500, r_thres = 0.95) # Different cutoffs could be specified metabProfile.clean <- ProfileCleanUp(metabProfile, timeSplit = 1000, r_thres = 0.9)# load example data require(TargetSearchData) data(TSExample) RI.path <- tsd_data_path() refLibrary <- ImportLibrary(tsd_file_path("library.txt")) # update RI file path RIpath(sampleDescription) <- RI.path # Import Library refLibrary <- ImportLibrary(tsd_file_path('library.txt')) # update median RI refLibrary <- medianRILib(sampleDescription, refLibrary) # get the sample RI corRI <- sampleRI(sampleDescription, refLibrary, r_thres = 0.95) # obtain the peak Intensities of all the masses in the library peakData <- peakFind(sampleDescription, refLibrary, corRI) metabProfile <- Profile(sampleDescription, refLibrary, peakData, r_thres = 0.95) # here we use the metabProfile previously calculated and return a "cleaned" profile. metabProfile.clean <- ProfileCleanUp(metabProfile, timeSplit = 500, r_thres = 0.95) # Different cutoffs could be specified metabProfile.clean <- ProfileCleanUp(metabProfile, timeSplit = 1000, r_thres = 0.9)
Create an intensity matrix using quantification masses. The quantification masses can be specified when importing the library file or automatically.
quantMatrix(Lib, metabProfile, value=c("quantmass", "maxint", "maxobs"), selmass=FALSE)quantMatrix(Lib, metabProfile, value=c("quantmass", "maxint", "maxobs"), selmass=FALSE)
Lib |
A |
metabProfile |
A |
value |
The method to select automatically the quantification mass. The options are: “maxint” which selects the selective mass with the highest median intensity across all samples; “maxobs” which selects the mass which the most observations (the one with fewer missing values; or “quantmass” which uses the selected quantification mass defined by the library |
selmass |
Logical. If |
An intensity matrix with metabolites as rows and samples as columns. The column
names are the sample names of the respective tsSample object and the rownames
correspond with the library unique identifiers.
In addition, the matrix has these attributes:
“quantMass” is a numeric vector that contains the quantification masses that was selected.
“isSelMass” is a logical vector that indicates whether the quantification mass is also a selected mass.
“isCorMass” to indicate that the mass is one of the correlating masses.
“libNames” the metabolite names (a character vector).
Alvaro Cuadros-Inostroza
require(TargetSearchData) data(TSExample) # process chromatograms and get a profile RI.path <- tsd_data_path() RIpath(sampleDescription) <- RI.path refLibrary <- ImportLibrary(tsd_file_path('library.txt')) refLibrary <- medianRILib(sampleDescription, refLibrary) corRI <- sampleRI(sampleDescription, refLibrary, r_thres = 0.95) peakData <- peakFind(sampleDescription, refLibrary, corRI) metabProfile <- Profile(sampleDescription, refLibrary, peakData, r_thres = 0.95) # get a Matrix using use default values, ie, use the quantification masses # defined in the library quantMat <- quantMatrix(refLibrary, metabProfile) quantMat # use 'maxint' to select the metabolites with the highest median intensity quantMat <- quantMatrix(refLibrary, metabProfile, 'maxint') # use 'maxobs' to select the metabolites with the most observed values quantMat <- quantMatrix(refLibrary, metabProfile, 'maxobs')require(TargetSearchData) data(TSExample) # process chromatograms and get a profile RI.path <- tsd_data_path() RIpath(sampleDescription) <- RI.path refLibrary <- ImportLibrary(tsd_file_path('library.txt')) refLibrary <- medianRILib(sampleDescription, refLibrary) corRI <- sampleRI(sampleDescription, refLibrary, r_thres = 0.95) peakData <- peakFind(sampleDescription, refLibrary, corRI) metabProfile <- Profile(sampleDescription, refLibrary, peakData, r_thres = 0.95) # get a Matrix using use default values, ie, use the quantification masses # defined in the library quantMat <- quantMatrix(refLibrary, metabProfile) quantMat # use 'maxint' to select the metabolites with the highest median intensity quantMat <- quantMatrix(refLibrary, metabProfile, 'maxint') # use 'maxobs' to select the metabolites with the most observed values quantMat <- quantMatrix(refLibrary, metabProfile, 'maxobs')
A convenient function to extract peak data from a RI file. This function is mostly
intended for debugging purposes, for example, when a given peak is not found within
a expected time range (which could be because a faulty retention time correction).
The arguments of this function are similar as those of the ncdf4_data_extract function.
ri_data_extract(RIfile, massValues, timeRange, useRT = FALSE, ...)ri_data_extract(RIfile, massValues, timeRange, useRT = FALSE, ...)
RIfile |
A path to a RI file format (binary or text). |
massValues |
A numeric vector representing m/z values. The values will be converted to integers internally. |
timeRange |
A numeric vector of even length, or, a two-column matrix. This parameter represents the lower and upper time limits. See details below. |
useRT |
Logical. If |
... |
Extra parameters passed to internal functions. Currently, only the |
The function takes a RI file generated by TargetSearch (binary or text works)
and extracts all the peaks detected of given m/z ion traces in a given time range.
The time range can be in seconds or arbitrary retention time index units.
The parameter timeRange can be either a numeric vector of even length or a
two-column matrix. If it is a matrix, the first column represent the lower bounds
while the second the upper ones. If it is a vector, it must have at least two elements,
which in this case represent the lower and upper limits, or if longer, it will be coerced to matrix
internally (Important: the values are filled by columns). In any case,
the number of rows of the (coerced) matrix must divide the length of the massValues
parameter, such that each row corresponds to a time range for each m/z value.
This is done so the ranges can be recycled.
The output is simply a four column matrix in which a row is a peak of a given ion trace at a retention time (index). The output is always a matrix even if no peaks are found, in which case the number of rows is zero.
A four column matrix with column names described below. Each row represents a peak in the specified time range. Potentially, there could be zero rows if no peaks are found.
RI retention time index of the peak.
RT retention time.
Intensity peak height intensity
mz the m/z of the peak
This function is intended to be used internally or by advances users. It can be used
for debugging when TargetSearch fails to find a peak.
See also the function FindAllPeaks which offers a similar functionality
but with different input parameters.
Alvaro Cuadros-Inostroza
text2bin,
ncdf4_data_extract,
FindAllPeaks,
FindPeaks
require(TargetSearchData) path <- tsd_data_path() rifile <- tsd_rifiles()[1] # extract peak data for m/z 116 and 117 in time range 180 - 220 seconds data <- ri_data_extract(rifile, c(116, 117), c(180, 220), useRT=TRUE) # same but using Retention Time Index data <- ri_data_extract(rifile, c(116, 117), c(205000, 228000), useRT=FALSE) # different time ranges for each m/z trange <- c(180, 240, 280, 190, 250, 290) data <- ri_data_extract(rifile, c(116, 144, 147), trange, useRT=TRUE) # Note: the range definition above is equivalent to trange <- cbind(c(180,240,280), c(190, 250, 290))require(TargetSearchData) path <- tsd_data_path() rifile <- tsd_rifiles()[1] # extract peak data for m/z 116 and 117 in time range 180 - 220 seconds data <- ri_data_extract(rifile, c(116, 117), c(180, 220), useRT=TRUE) # same but using Retention Time Index data <- ri_data_extract(rifile, c(116, 117), c(205000, 228000), useRT=FALSE) # different time ranges for each m/z trange <- c(180, 240, 280, 190, 250, 290) data <- ri_data_extract(rifile, c(116, 144, 147), trange, useRT=TRUE) # Note: the range definition above is equivalent to trange <- cbind(c(180,240,280), c(190, 250, 290))
Plot retention index or time of peaks from RI files or samples. This is a low level
interface to plotPeakRI that not relies on a metabolite library.
This function is useful for quick peak data visualization.
ri_plot_peak(obj, massValues, timeRange, useRT = TRUE, showRT = useRT, sizefun = NULL, plot = TRUE, ...)ri_plot_peak(obj, massValues, timeRange, useRT = TRUE, showRT = useRT, sizefun = NULL, plot = TRUE, ...)
obj |
Either a |
massValues |
A numeric vector representing m/z values. |
timeRange |
A numeric vector of length 2 representing the lower and upper time limits. |
useRT |
Logical. If |
showRT |
Logical. Whether the x-axis of the resulting plot should represent seconds
( |
sizefun |
A function that could be used to scale the point size of the plot via the
parameter 'cex', for example, to scale the peak intensity. This function should take a numeric
vector as input and return a positive value. If |
plot |
Logical. If |
... |
Extra arguments, such as |
The function uses internally ri_data_extract wrapped with a call to
lapply. Because the output of lapply is
a list, the list is transformed to a matrix by calling rbind. A column
of sample indices called sample is added so each row can be traced back to a sample.
The x-axis of the plot are indexed samples (or RI files), i.e., first sample is 1,
second 2, and so on. The y-axis is retention time (RT) or retention index (RI)
depending on the value of showRT. Note that you can search by RT and plot
by RI depending on the value of useRT.
Plot styling can be achieved by passing plotting extra parameters such as col, pch,
lty, and others (see par and plot).
Because the styles can be applied per sample or per m/z value, it is possible
to prefix a ‘s’ to those parameters to specify that the style applies to samples and
no masses. The available parameters are scol, spch, sbg and scex.
See examples and also the notes below.
The parameter sizefun is a function that takes a numeric vector as input and
returns a positive value which correspond to the point size (parameter cex).
This function will be applied on the peak intensities and the result will be used as cex.
If NULL, the scaling function is implemented as (log10(x/100) * (9/8) + (1/2),
where x is the peak intensity. Note that if either cex or scex is
passed to the function, then sizefun will have no effect.
The logical parameter plot controls whether a plot is drawn. This might be useful
for simply extracting the data for custom plotting with other packages such as ggplot2.
Returns invisible or a five-column matrix (see below), where the number
of rows correspond to the number of peaks (or points) in the searched range. If no peaks
are found in the given range, then it returns NULL.
RI retention time index or the peak.
RT retention time.
Intensity peak height intensity.
mz the m/z of the peak.
sample an integer representing the sample index.
Compare this list with ri_data_extract.
This function is intended for advanced users and for debugging purposes when TargetSearch
fails to detect a peak.
Not all graphical parameters passed by ... will work, in particular
panel.first and panel.last are known to not work.
Therefore, for more personalized plots, it is recommended to set plot=FALSE
and use the returned data for plotting.
Alvaro Cuadros-Inostroza
require(TargetSearchData) # get RI files from TargetSearchData path <- tsd_data_path() rifiles <- tsd_rifiles() # simple plot no style z <- ri_plot_peak(rifiles, massValues=c(144, 145, 100, 218), timeRange=c(255, 265)) # watch output data head(z) # add some style ri_plot_peak(rifiles, massValues=c(144, 145, 100, 218), timeRange=c(255, 265), pch=1:4, col=1:4) # display the Retention Index instead ri_plot_peak(rifiles, massValues=c(144, 145, 100, 218), timeRange=c(255, 265), pch=1:4, col=1:4, showRT=FALSE) # use RI index for the time range ri_plot_peak(rifiles, massValues=c(144, 145, 100, 218), timeRange=c(267000, 275000), useRT=FALSE, pch=1:4, col=1:4) # use styling per sample scol <- rep(1:5, each=3) ri_plot_peak(rifiles, massValues=c(144), timeRange=c(255, 265), pch=19, scol=scol) # using a tsSample object can achieve the same results (RI files are in text format) smp <- ImportSamplesFromDir(path, ftype = "text") ri_plot_peak(smp, massValues=c(144), timeRange=c(255, 265), pch=19, scol=scol)require(TargetSearchData) # get RI files from TargetSearchData path <- tsd_data_path() rifiles <- tsd_rifiles() # simple plot no style z <- ri_plot_peak(rifiles, massValues=c(144, 145, 100, 218), timeRange=c(255, 265)) # watch output data head(z) # add some style ri_plot_peak(rifiles, massValues=c(144, 145, 100, 218), timeRange=c(255, 265), pch=1:4, col=1:4) # display the Retention Index instead ri_plot_peak(rifiles, massValues=c(144, 145, 100, 218), timeRange=c(255, 265), pch=1:4, col=1:4, showRT=FALSE) # use RI index for the time range ri_plot_peak(rifiles, massValues=c(144, 145, 100, 218), timeRange=c(267000, 275000), useRT=FALSE, pch=1:4, col=1:4) # use styling per sample scol <- rep(1:5, each=3) ri_plot_peak(rifiles, massValues=c(144), timeRange=c(255, 265), pch=19, scol=scol) # using a tsSample object can achieve the same results (RI files are in text format) smp <- ImportSamplesFromDir(path, ftype = "text") ri_plot_peak(smp, massValues=c(144), timeRange=c(255, 265), pch=19, scol=scol)
Convert retention time indices to retention times indices based on observed FAME RI and their standard values.
ri2rt(riTime, rt.observed, ri.standard)ri2rt(riTime, rt.observed, ri.standard)
riTime |
And RI vector or matrix to convert to Retention Time. |
rt.observed |
The observed FAME RT's. It could be a vector or a matrix. |
ri.standard |
The standard RI for each FAME |
This function is the inverse of rt2ri.
The converted RT
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
# RI standards standard <- c(100, 200, 300, 400, 500) # observed standard retention times observed <- c(10.4, 19.3, 32.4, 40.2, 50.3) # a random set of retention times RI <- runif(100,90,600) # the corrected RIs RT <- ri2rt(RI, observed, standard)# RI standards standard <- c(100, 200, 300, 400, 500) # observed standard retention times observed <- c(10.4, 19.3, 32.4, 40.2, 50.3) # a random set of retention times RI <- runif(100,90,600) # the corrected RIs RT <- ri2rt(RI, observed, standard)
This function reads from CDF files, finds the apex intensities, converts the retention time to retention time index (RI), and writes RI corrected text files (a.k.a. RI files). In addition, it can perform baseline correction and also convert files to the new NetCDF-4 TargetSearch format.
RIcorrect(samples, rimLimits = NULL, massRange=NULL, Window, IntThreshold, pp.method="ppc", showProgressBar=FALSE, baseline=FALSE, writeCDF4path=TRUE, ...)RIcorrect(samples, rimLimits = NULL, massRange=NULL, Window, IntThreshold, pp.method="ppc", showProgressBar=FALSE, baseline=FALSE, writeCDF4path=TRUE, ...)
samples |
A |
rimLimits |
A |
massRange |
Deprecated. It is completely ignored but it is kept for compatibility with old scripts. |
Window |
The window used for smoothing. The number of points actually used
is |
IntThreshold |
Apex intensities lower than this value will be removed from the RI files. |
pp.method |
Peak picking method. Options are "smoothing", "gaussian" and "ppc". See details. |
showProgressBar |
Logical. Should the progress bar be displayed? |
baseline |
Logical. Should baseline correction be performed? |
writeCDF4path |
Whether or not convert a CDF-3 into a CDF-4. It can take a logical value or a character vector representing file paths. See details below. |
... |
A list of options passed to |
There are three pick picking methods available: "ppc", "smoothing", "gaussian".
The "ppc" method (default) implements the peak detection method described in the ppc
package. It looks for the local maxima within a 2*Window + 1 scans for
every mass trace.
The "smoothing" method calculates a moving average of 2*Window + 1 points
for every mass trace. Then it looks for a change of sign (from positive to negative) of
the difference between two consecutive points. Those points will be returned as
detected peaks.
The "gaussian" method behaves similar to the "smoothing" method, but instead a gaussian smoother is used instead of the moving average.
To work out a suitable Window value, the following might be useful:
Window = (SR * PW - 1) / 2, where SR is the scan rate of the MS instrument and
PW is the peak width. Because Window is an integer, the resulting value must be
rounded. For example, for SR = 20 scans per second, a PW = 1.5 seconds, then
Window = 14.5, which can be rounded to 15.
The RI file type is determined by the output of fileFormat
method applied to the tsSample input object. To
choose between the available formats ("binary" and "text"), select it
with fileFormat method before calling RIcorrect.
The parameter writeCDF4path is used to convert CDF-3 files into a
custom CDF-4 format. It can be logical or a character vector. If TRUE,
the default, the CDF-3 files will be converted automatically to CDF-4
format. The files will be saved in the same directory as the original CDF-3.
If it is character vector representing file paths, then the CDF-4 will be
saved in those paths instead (re-cycled to the length of samples).
Finally, if FALSE, then no CDF conversion will be performed. This is not
recommended, but if possible if you want to match the old TargetSearch
behaviour. Note that also the baseline correction or the retention
time indices will not be updated as well.
If baseline is TRUE, the CDF files will be baseline corrected
by passing the extra parameters to baseline. See there for
details.
A retention time matrix of the found retention time markers. Every column represents a sample and rows RT markers.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
ImportSamples, ImportFameSettings,
NetCDFPeakFinding, FAMEoutliers,
tsSample, tsRim.
require(TargetSearchData) # import refLibrary, rimLimits and sampleDescription. data(TSExample) # get the CDF files cdfpath <- tsd_data_path() cdfpath list.files(cdfpath) # update the CDF path CDFpath(sampleDescription) <- cdfpath # change file format of RI files as bin fileFormat(sampleDescription) <- 'binary' # Parameters: Intensity Threshold = 50 peak detection method = "ppc", window = 15 # To match the old behavior, the do not create CDF-4 Files (not recommended) RImatrix <- RIcorrect(sampleDescription, rimLimits, writeCDF4path=FALSE, Window = 15, pp.method = "ppc", IntThreshold = 50) # Convert to CDF-4 (recommended) with same parameters # Note: save files in same directory (as RImatrix <- RIcorrect(sampleDescription, rimLimits, writeCDF4path=".", Window = 15, pp.method = "ppc", IntThreshold = 50) # we need to update the sampleDescription to use the new files # this is not done automatically sampleDescription <- ncdf4Convert(sampleDescription, ".") # you can try other parameters and other peak picking algorithm RImatrix <- RIcorrect(sampleDescription, rimLimits, Window = 15, pp.method = "smoothing", IntThreshold = 10) RImatrix <- RIcorrect(sampleDescription, rimLimits, Window = 15, pp.method = "ppc", IntThreshold = 100)require(TargetSearchData) # import refLibrary, rimLimits and sampleDescription. data(TSExample) # get the CDF files cdfpath <- tsd_data_path() cdfpath list.files(cdfpath) # update the CDF path CDFpath(sampleDescription) <- cdfpath # change file format of RI files as bin fileFormat(sampleDescription) <- 'binary' # Parameters: Intensity Threshold = 50 peak detection method = "ppc", window = 15 # To match the old behavior, the do not create CDF-4 Files (not recommended) RImatrix <- RIcorrect(sampleDescription, rimLimits, writeCDF4path=FALSE, Window = 15, pp.method = "ppc", IntThreshold = 50) # Convert to CDF-4 (recommended) with same parameters # Note: save files in same directory (as RImatrix <- RIcorrect(sampleDescription, rimLimits, writeCDF4path=".", Window = 15, pp.method = "ppc", IntThreshold = 50) # we need to update the sampleDescription to use the new files # this is not done automatically sampleDescription <- ncdf4Convert(sampleDescription, ".") # you can try other parameters and other peak picking algorithm RImatrix <- RIcorrect(sampleDescription, rimLimits, Window = 15, pp.method = "smoothing", IntThreshold = 10) RImatrix <- RIcorrect(sampleDescription, rimLimits, Window = 15, pp.method = "ppc", IntThreshold = 100)
A function to search for retention index RI markers.
riMatrix(samples, rim)riMatrix(samples, rim)
samples |
A |
rim |
A |
This function works similar to RIcorrect, but searches
for RI markers in RI files (not in CDF files). Can be used to retrieve
the retention times of RI markers in already processed files.
Note that it does not perform any RI adjustment. See fixRI.
A retention time matrix of the found retention time markers. Every column represents a sample and rows RT markers.
In case the RI files are in text format and their column names are not standard (for
example, when the files were generated with another software), use the global option
'TS_RI_columns' or transform the RI files to TargetSearch binary
format. See the documentation in function text2bin.
Alvaro Cuadros-Inostroza
RIcorrect, FAMEoutliers,ImportSamples,
ImportFameSettings, fixRI
require(TargetSearchData) # import refLibrary, rimLimits and sampleDescription. data(TSExample) # get the CDF files cdfpath <- tsd_data_path() # select a subset of samples smp <- sampleDescription[1:4] # update the CDF path CDFpath(smp) <- cdfpath # make a copy of the RI markers object rim <- rimLimits # run RIcorrect RImat <- RIcorrect(smp, rim, massRange = c(85,320), writeCDF4path=FALSE, Window = 15, pp.method = "ppc", IntThreshold = 50) # extract the retention times of the markers RImat2 <- riMatrix(smp, rim) # both matrices should be equal stopifnot( all.equal(RImat, RImat2, tolerance=1e-8) )require(TargetSearchData) # import refLibrary, rimLimits and sampleDescription. data(TSExample) # get the CDF files cdfpath <- tsd_data_path() # select a subset of samples smp <- sampleDescription[1:4] # update the CDF path CDFpath(smp) <- cdfpath # make a copy of the RI markers object rim <- rimLimits # run RIcorrect RImat <- RIcorrect(smp, rim, massRange = c(85,320), writeCDF4path=FALSE, Window = 15, pp.method = "ppc", IntThreshold = 50) # extract the retention times of the markers RImat2 <- riMatrix(smp, rim) # both matrices should be equal stopifnot( all.equal(RImat, RImat2, tolerance=1e-8) )
Convert retention times to retention indices based on observed FAME RI and their standard values.
rt2ri(rtTime, observed, standard)rt2ri(rtTime, observed, standard)
rtTime |
The extracted RT's to convert |
observed |
The observed FAME RT's |
standard |
The standard RI for each FAME |
Linear interpolation, interpolation outside bounds are done with continued linear interpolation from the last two FAME's
The converted RI
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
# RI standards standard <- c(100, 200, 300, 400, 500) # observed standard retention times observed <- c(10.4, 19.3, 32.4, 40.2, 50.3) # a random set of retention times RT <- runif(100,1,60) # the corrected RIs RI <- rt2ri(RT, observed, standard)# RI standards standard <- c(100, 200, 300, 400, 500) # observed standard retention times observed <- c(10.4, 19.3, 32.4, 40.2, 50.3) # a random set of retention times RT <- runif(100,1,60) # the corrected RIs RI <- rt2ri(RT, observed, standard)
Return a matrix of the sample specific retention indices (RI) based on the correlating selective masses.
sampleRI(samples, Lib, r_thres = 0.95, columns = NULL, method = "dayNorm", minPairObs = 5, showProgressBar = FALSE, makeReport = FALSE, pdfFile = "medianLibRep.pdf")sampleRI(samples, Lib, r_thres = 0.95, columns = NULL, method = "dayNorm", minPairObs = 5, showProgressBar = FALSE, makeReport = FALSE, pdfFile = "medianLibRep.pdf")
samples |
A |
Lib |
A |
r_thres |
A correlation threshold. |
columns |
Either |
method |
Normalization method. Options are |
minPairObs |
Minimum number of pair observations. Correlations between two variables are computed using all complete pairs of observations in those variables. If the number of observations is too small, you may get high correlations values just by chance, so this parameters is used to avoid that. Cannot be set lower than 5. |
showProgressBar |
Logical. Should the progress bar be displayed? |
makeReport |
Logical. If |
pdfFile |
The file name where the report will be saved. |
A matrix of correlating selective masses RI. Columns represent samples and rows the median RI of the selective masses.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
ImportSamples, ImportLibrary,
medianRILib, tsLib, tsSample
require(TargetSearchData) data(TSExample) # get RI file path RI.path <- tsd_data_path() # update RI file path RIpath(sampleDescription) <- RI.path # Import Library refLibrary <- ImportLibrary(tsd_file_path('library.txt')) # get the sample RI corRI <- sampleRI(sampleDescription, refLibrary, r_thres = 0.95) # same as above, but changing the correlation threshold and the minimum number # of observations corRI <- sampleRI(sampleDescription, refLibrary, r_thres = 0.9, minPairObs = 10)require(TargetSearchData) data(TSExample) # get RI file path RI.path <- tsd_data_path() # update RI file path RIpath(sampleDescription) <- RI.path # Import Library refLibrary <- ImportLibrary(tsd_file_path('library.txt')) # get the sample RI corRI <- sampleRI(sampleDescription, refLibrary, r_thres = 0.95) # same as above, but changing the correlation threshold and the minimum number # of observations corRI <- sampleRI(sampleDescription, refLibrary, r_thres = 0.9, minPairObs = 10)
Functions listed here are defunct and no longer available.
These function have been removed from ‘TargetSearch’ and no longer available. Use the replacement if any.
fixRIcorrection has been replaced by fixRI.
TargetSearchGUI has been removed. Please use regular
‘TargetSearch’ functions. The old source code is archived at
https://github.com/acinostroza/TargetSearchGUI.
The functions listed here have been deprecated and may be removed as soon as of the next release.
These functions are deprecated. Use the replacement if available.
This function converts a list of RI files (also known as peak list files) in text or binary format to binary or text format.
text2bin(in.files, out.files=NULL, columns=NULL) bin2text(in.files, out.files=NULL)text2bin(in.files, out.files=NULL, columns=NULL) bin2text(in.files, out.files=NULL)
in.files |
A character vector of file paths to the input RI files. |
out.files |
A character vector of file paths. If |
columns |
Either a numeric vector with the positions of the columns for |
These functions transform a list of RI files from and to binary to text representation. The format of the input files is detected dynamically and an error will be issued on invalid files.
Transforming a binary file to text might be useful if you need to inspect what a RI file looks in the inside (for example, you need to check that the peak detection was correct). On the other hand, a text file to binary is highly recommended as it is faster to parse than a text file.
For text files, the order of the columns is important (see option columns above). The first
entry is the spectrum list, followed by the retention time index and the retention time. If the
column names are other than SPECTRUM, RETENTION_TIME_INDEX, and RETENTION_TIME,
use the respective column names or the column names positions starting at zero (first column
is zero, second is one, and so on).
Many functions relay on those column names and having to pass them as arguments on each function
is tedious, so the global option TS_RI_columns can be set at the beginning, for example:
# using column names
options(TS_RI_columns=c('spec_column', 'RI_column', 'RT_column'))
# using column indices (zero-based!)
options(TS_RI_columns=c(1, 2, 0))
where "spec_column", "RI_column", and "RT_columns" are the names of the spectrum, retention index and retention time columns.
This command is useful if your RI files were generated by another software. However, it
is highly recommended to simple convert those custom RI files into TargetSearch's binary
format and do not worry about column names.
A character vector of the created files paths or invisible.
The so-called RI files contain lists of m/z peaks detected for every ion trace measured in the samples. Historically, the file format was a simple tab-delimited text file in the format described below. Note that the column order could differ and additional columns could be present, but they are ignored.
| RETENTION_TIME | SPECTRUM | RETENTION_TIME_INDEX |
| 212.46 | 250:26 256:26 316:27 | 221029.7 |
| 212.51 | 114:46 162:30 251:27 | 221081.3 |
| 212.56 | 319:25 | 221132.9 |
| 212.61 | 95:38 108:30 262:32 266:27 292:25 | 221184.5 |
The retention time is usually represented in seconds, while the retention time in arbitrary units, which depends on the retention time correction standard method (in the table above it is in milliseconds, but other units can be used).
The spectrum column is represented by pairs of m/z and raw intensity (peak height), similarly
as the representation of a metabolite library (see ImportLibrary). Thus each
pair correspond to a peak of the respective ion trace.
The disadvantage of using text files is they are slow to parse, so a binary format was created
which represents the peak data as binary vectors so they are fast to parse. These files contain
the extension dat.
Beware that the respective tsSample object may need to be updated by using
the method fileFormat.
Alvaro Cuadros-Inostroza
ImportSamples, tsSample,
RIcorrect
require(TargetSearchData) # take three example files from package TargetSearchData in.files <- tsd_rifiles()[1:3] # out files to current directory out.files <- sub(".txt", ".dat", basename(in.files)) # convert to binary format res <- text2bin(in.files, out.files) stopifnot(res == out.files) # convert back to text res <- bin2text(out.files) stopifnot(res == basename(in.files)) # Demonstrate how to use the `columns` option # make dummy RI file with arbitrary column names and save it tmp <- data.frame(RT=c(101.5,102.5), SPEC=c('12:100 23:100', '114:46 162:30'), RI=c(300, 400) + .75) # file must be tab-delimited, unquoted strings and no row names RI_test <- tempfile(fileext=".txt") write.table(tmp, file=RI_test, sep="\t", quote=FALSE, row.names=FALSE) # convert this text file to binary format ## wrong! It fails because of invalid columns # text2bin(RI_test) # correct! The columns are correct text2bin(RI_test, columns=c('SPEC', 'RI', 'RT')) # same example but using integers (not recommended) text2bin(RI_test, columns=c(1, 2, 0)) # note they start from zero. # Alternative, set a global option (so it can be used in a session) opt <- options(TS_RI_columns=c('SPEC', 'RI', 'RT')) text2bin(RI_test) # or using integers (again, not recommended) options(TS_RI_columns=c(1, 2, 0)) text2bin(RI_test) # unset options options(opt)require(TargetSearchData) # take three example files from package TargetSearchData in.files <- tsd_rifiles()[1:3] # out files to current directory out.files <- sub(".txt", ".dat", basename(in.files)) # convert to binary format res <- text2bin(in.files, out.files) stopifnot(res == out.files) # convert back to text res <- bin2text(out.files) stopifnot(res == basename(in.files)) # Demonstrate how to use the `columns` option # make dummy RI file with arbitrary column names and save it tmp <- data.frame(RT=c(101.5,102.5), SPEC=c('12:100 23:100', '114:46 162:30'), RI=c(300, 400) + .75) # file must be tab-delimited, unquoted strings and no row names RI_test <- tempfile(fileext=".txt") write.table(tmp, file=RI_test, sep="\t", quote=FALSE, row.names=FALSE) # convert this text file to binary format ## wrong! It fails because of invalid columns # text2bin(RI_test) # correct! The columns are correct text2bin(RI_test, columns=c('SPEC', 'RI', 'RT')) # same example but using integers (not recommended) text2bin(RI_test, columns=c(1, 2, 0)) # note they start from zero. # Alternative, set a global option (so it can be used in a session) opt <- options(TS_RI_columns=c('SPEC', 'RI', 'RT')) text2bin(RI_test) # or using integers (again, not recommended) options(TS_RI_columns=c(1, 2, 0)) text2bin(RI_test) # unset options options(opt)
A TargetSearch example GC-MS data. This datasets contains TargetSearch object
examples generated from a E.coli salt stress experiment (See package TargetSearchData).
data(TSExample)data(TSExample)
The data contains the following objects:
a tsSample object. The sample description.
a tsLib object. The reference library.
a tsRim object. The RI markers definition.
a matrix object. The retention time of the RI markers.
a matrix object. The sample RI.
a tsMSdata object. The intensities and RIs of all the
masses that were searched for.
a tsProfile object. The metabolite profile.
This dataset contain only the objects. The actual source files are provided by the package TargetSearchData.
ImportLibrary,
ImportSamples,
ImportFameSettings,
# this run an example pipeline require(TargetSearchData) ## The directory with the NetCDF GC-MS files cdfpath <- tsd_data_path() cdfpath list.files(cdfpath) # get files from TargetSearchData samp.file <- tsd_file_path("samples.txt") rim.file <- tsd_file_path("rimLimits.txt") lib.file <- tsd_file_path("library.txt") # import files from package sampleDescription <- ImportSamples(samp.file, CDFpath = cdfpath, RIpath = ".") refLibrary <- ImportLibrary(lib.file) rimLimits <- ImportFameSettings(rim.file, mass = 87) # update NCDF4 sampleDescription <- ncdf4Convert(sampleDescription, path=".") # perform RI correction RImatrix <- RIcorrect(sampleDescription, rimLimits, massRange = c(85,320), IntThreshold = 25, pp.method = "ppc", Window = 15) # update median RI refLibrary <- medianRILib(sampleDescription, refLibrary) # get the sample RI corRI <- sampleRI(sampleDescription, refLibrary, r_thres = 0.95) # obtain the peak Intensities of all the masses in the library peakData <- peakFind(sampleDescription, refLibrary, corRI) # make a profile of the metabolite data metabProfile <- Profile(sampleDescription, refLibrary, peakData, r_thres = 0.95) # show the metabolite profile profileInfo(metabProfile) # show the matrix intensities Intensity(metabProfile)# this run an example pipeline require(TargetSearchData) ## The directory with the NetCDF GC-MS files cdfpath <- tsd_data_path() cdfpath list.files(cdfpath) # get files from TargetSearchData samp.file <- tsd_file_path("samples.txt") rim.file <- tsd_file_path("rimLimits.txt") lib.file <- tsd_file_path("library.txt") # import files from package sampleDescription <- ImportSamples(samp.file, CDFpath = cdfpath, RIpath = ".") refLibrary <- ImportLibrary(lib.file) rimLimits <- ImportFameSettings(rim.file, mass = 87) # update NCDF4 sampleDescription <- ncdf4Convert(sampleDescription, path=".") # perform RI correction RImatrix <- RIcorrect(sampleDescription, rimLimits, massRange = c(85,320), IntThreshold = 25, pp.method = "ppc", Window = 15) # update median RI refLibrary <- medianRILib(sampleDescription, refLibrary) # get the sample RI corRI <- sampleRI(sampleDescription, refLibrary, r_thres = 0.95) # obtain the peak Intensities of all the masses in the library peakData <- peakFind(sampleDescription, refLibrary, corRI) # make a profile of the metabolite data metabProfile <- Profile(sampleDescription, refLibrary, peakData, r_thres = 0.95) # show the metabolite profile profileInfo(metabProfile) # show the matrix intensities Intensity(metabProfile)
This is a class representation of a reference library.
Objects can be created by the function ImportLibrary.
Name:"character", the metabolite or analyte names.
RI:"numeric", the expected retention time indices (RI) of the metabolites/analytes.
medRI:"numeric", the median RI calculated from the samples.
RIdev:"matrix", the RI deviation windows, k = 1,2,3. A three column matrix
selMass:"list", every component is a numeric vector containing the selective masses.
topMass:"list", every component is a numeric vector containing the top masses.
quantMass:"numeric", the mass used for quantification.
libData:"data.frame", additional library information.
spectra:"list", the metabolite spectra. Each component is a two column matrix: m/z and intensity.
[signature(x = "tsLib"): Selects a subset of metabolites from the library.
$namesignature(x = "tsLib"): Access column name of libData slot.
libIdsignature(obj = "tsLib"): Returns a vector of indices.
lengthsignature(x = "tsLib"): returns the length of the library. i.e., number of metabolites.
libDatasignature(obj = "tsLib"): gets/sets the libData slot.
libNamesignature(obj = "tsLib"): gets the Name slot.
libRIsignature(obj = "tsLib"): gets the RI slot.
medRIsignature(obj = "tsLib"): gets the medRI slot.
refLibsignature(obj = "tsLib"): Low level method to create a matrix representation of the library.
RIdevsignature(obj = "tsLib"): gets the RI deviations.
RIdev<-signature(obj = "tsLib"): sets the RI deviations.
quantMasssignature(obj = "tsLib"): gets the quantification mass.
quantMass<-signature(obj = "tsLib"): sets the quantification mass.
selMasssignature(obj = "tsLib"): gets the selective masses.
showsignature(object = "tsLib"): show method.
spectrasignature(obj = "tsLib"): gets the spectra.
topMasssignature(obj = "tsLib"): gets the top masses.
cCombine two or more tsLib objects.
Some care is needed when using the methods quantMass<-, selMass<-, topMass<-.
In order to be consistent, the first m/z value of the slot topMass and selMass are
equal to quantMass, and the values of selMass are equal to the first couple of values
of topMass. In other words, the following constrain is applied.
quantMass : x[0]
selMass : x[0], x[1], ..., x[k]
topMass : x[0], x[1], ..., x[k], x[k+1], ..., x[n]
where 1 <= k <= n and x[i] is a m/z value. Thus, using one these methods will
change the values of the other slots. In the future, these methods will be deprecated, so it
is better to not rely on them.
See the last example on how this can lead to unexpected results.
The c method requires that the combination of all objects have unique identifiers (names),
or in other words, the objects cannot share identifiers. Duplicated identifiers are not
allowed and an error will be thrown. This method also requires that the column names of the
libData slot (see method libData) are the same, because the method calls
rbind internally.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
showClass("tsLib") # define some metabolite names libNames <- c("Metab1", "Metab2", "Metab3") # the expected retention index RI <- c(100,200,300) # selective masses to search for. A list of vectors. selMasses <- list(c(95,204,361), c(87,116,190), c(158,201,219)) # define the retention time windows to look for the given selective masses. RIdev <- matrix(rep(c(10,5,2), length(libNames)), ncol = 3, byrow = TRUE) # Set the mass spectra. A list object of two-column matrices, or set to # NULL if the spectra is not available spectra <- NULL # some extra information about the library libData <- data.frame(Name = libNames, Lib_RI = RI) # create a reference library object refLibrary <- new("tsLib", Name = libNames, RI = RI, medRI = RI, RIdev = RIdev, selMass = selMasses, topMass = selMasses, spectra = spectra, libData = libData) # get the metabolite names libName(refLibrary) # set new names libName(refLibrary) <- c("Metab01", "Metab02", "Metab03") # get the expected retention times libRI(refLibrary) # set the retention time index for metabolite 3 to 310 seconds libRI(refLibrary)[3] <- 310 # change the selection and top masses of metabolite 3 selMass(refLibrary)[[3]] <- c(158,201,219,220,323) topMass(refLibrary)[[3]] <- c(158,201,219,220,323) # change the retention time deviations RIdev(refLibrary)[3,] <- c(8,4,1) ##################################################################### # objects can be subset and combined with the `[` and `c` operators lib1 <- refLibrary[1:2] lib2 <- refLibrary[3] lib <- c(lib1, lib2) # this restores the object refLibrary ##################################################################### # These examples show how changing a quantitaive or selective mass # could lead to unexpected results. # show quantMasses quantMass(refLibrary) # suppose that we want to change the quant mass of metabolite 1 to 96 due # to a typo in the library. We could do just quantMass(refLibrary)[1] <- 96 # however, we still see the mass 95 in the selective and top masses. selMass(refLibrary)[[1]] topMass(refLibrary)[[1]] # to remove the mass 95, set the topMass and selMass explicitly, noting that # the first masses coincides with 96 (the quantMass) selMass(refLibrary)[[1]] <- c(96, 204, 361) topMass(refLibrary)[[1]] <- c(96, 204, 361)showClass("tsLib") # define some metabolite names libNames <- c("Metab1", "Metab2", "Metab3") # the expected retention index RI <- c(100,200,300) # selective masses to search for. A list of vectors. selMasses <- list(c(95,204,361), c(87,116,190), c(158,201,219)) # define the retention time windows to look for the given selective masses. RIdev <- matrix(rep(c(10,5,2), length(libNames)), ncol = 3, byrow = TRUE) # Set the mass spectra. A list object of two-column matrices, or set to # NULL if the spectra is not available spectra <- NULL # some extra information about the library libData <- data.frame(Name = libNames, Lib_RI = RI) # create a reference library object refLibrary <- new("tsLib", Name = libNames, RI = RI, medRI = RI, RIdev = RIdev, selMass = selMasses, topMass = selMasses, spectra = spectra, libData = libData) # get the metabolite names libName(refLibrary) # set new names libName(refLibrary) <- c("Metab01", "Metab02", "Metab03") # get the expected retention times libRI(refLibrary) # set the retention time index for metabolite 3 to 310 seconds libRI(refLibrary)[3] <- 310 # change the selection and top masses of metabolite 3 selMass(refLibrary)[[3]] <- c(158,201,219,220,323) topMass(refLibrary)[[3]] <- c(158,201,219,220,323) # change the retention time deviations RIdev(refLibrary)[3,] <- c(8,4,1) ##################################################################### # objects can be subset and combined with the `[` and `c` operators lib1 <- refLibrary[1:2] lib2 <- refLibrary[3] lib <- c(lib1, lib2) # this restores the object refLibrary ##################################################################### # These examples show how changing a quantitaive or selective mass # could lead to unexpected results. # show quantMasses quantMass(refLibrary) # suppose that we want to change the quant mass of metabolite 1 to 96 due # to a typo in the library. We could do just quantMass(refLibrary)[1] <- 96 # however, we still see the mass 95 in the selective and top masses. selMass(refLibrary)[[1]] topMass(refLibrary)[[1]] # to remove the mass 95, set the topMass and selMass explicitly, noting that # the first masses coincides with 96 (the quantMass) selMass(refLibrary)[[1]] <- c(96, 204, 361) topMass(refLibrary)[[1]] <- c(96, 204, 361)
This is a class to represent MS data obtained from the sample.
The method as.list converts every slot (RI, RT, and Intensity)
of a tsMSdata object into a matrix. The converted matrices
are stored in a list. Each converted matrix has an attribute called 'index' that
relates the metabolite index with the respective rows. The components
of the resulting list are named as the slots. If the slot RT is
not defined or empty, then the output list will have only two components.
('RT' and 'Intensity').
These objects are created by the functions FindPeaks and
peakFind and there is really no need to create them manually,
so the examples focus on simple data manipulations.
The assignment methods retIndex<-, retTime<-, and
Intensity<- are exposed for convenience, though they should not be
needed in general. These objects are tightly coupled to the reference library
(tsLib) and sample (tsSample)
objects, so a modification could cause unexpected errors. Use under your own
risk if you know what you are doing.
Objects be created by calling the functions FindPeaks or
peakFind. See their respective documentation.
RI:"list", a list containing an RI matrix, one matrix per metabolite
RT:"list", a list containing an RT matrix, one matrix per metabolite
Intensity:"list", a list containing a peak intensity matrix, one matrix per metabolite
signature(obj = "tsMSdata"): gets the peak intensity list.
signature(obj = "tsMSdata"): gets the peak intensity list.
signature(obj = "tsMSdata"): gets RT list.
signature(obj = "tsMSdata"): sets the RI list.
signature(obj = "tsMSdata"): gets the RT list.
signature(obj = "tsMSdata"): sets the RT list.
signature(object = "tsMSdata"): show function.
signature(object = "tsMSdata"): coerce a list object. See details
For reasons explained in the details section, the methods retIndex<-,
retTime<-, and Intensity<- are considered deprecated
and could be removed without notice in the feature.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
showClass("tsMSdata") # some example manipulations using object peakData data(TSExample) peakData # extract the intensities of the metabolites int <- Intensity(peakData) # `int` is a list of matrices where rows are m/z values and columns are samples head(int) # extract retention indices (same structure for the intensities) ri <- retIndex(peakData) head(ri) # coerce the whole object into a list of matrices (see details) data <- as.list(peakData) # it is possible to use the assignment methods `retIndex<-` and `Intensity<-` # in these objects, but it is not recommended (only if you know what you are # doing) for example for small tweaks (not sure what this accomplishes however) ri[[1]][1,1] <- 234000 retIndex(peakData) <- rishowClass("tsMSdata") # some example manipulations using object peakData data(TSExample) peakData # extract the intensities of the metabolites int <- Intensity(peakData) # `int` is a list of matrices where rows are m/z values and columns are samples head(int) # extract retention indices (same structure for the intensities) ri <- retIndex(peakData) head(ri) # coerce the whole object into a list of matrices (see details) data <- as.list(peakData) # it is possible to use the assignment methods `retIndex<-` and `Intensity<-` # in these objects, but it is not recommended (only if you know what you are # doing) for example for small tweaks (not sure what this accomplishes however) ri[[1]][1,1] <- 234000 retIndex(peakData) <- ri
This is class used to represent a metabolite profile obtained with
TargetSearch. This class contains the data you are most
likely to use in downstream data analysis.
The metabolite profile information (slot info) is a data.frame
that contains information regarding each target metabolite in the reference
library (object tsLib). The information can be accessed
with the method profileInfo. The profile include the following
columns,
Name The metabolite/analyte name.
Lib_RI The reference or expected RI (retention index).
Mass_count The number of correlating masses.
Non_consecutive_Mass_count Same as mass count, but
discounting consecutive masses that correspond with isotopic peaks, which
often correlate anyway.
Sample_Count_per_Mass The number of samples in which each
correlating mass was found. The values are separated by colons (;).
The values of the actual masses are in following column.
Masses The correlating masses separated by colons (;).
RI The average RI detected in the samples.
Score_all_masses The similarity score calculated using the
average intensity of all the masses that were searched for, regardless of
whether they are correlating masses.
Score_cor_masses Same as above, but only correlating masses
are considered.
Other columns could be present by they are carried over from the metabolite
library tsLib object.
If the object is created by the function ProfileCleanUp instead,
additional columns will be created with the prefix Cor_ followed
by a string, such as Cor_RI. These columns contain information
of “collapsed” metabolites that correlate to mean that they could
conflict. The collapsed values are often separated by a vertical bar |.
The slots profRT, profRI and profInt contain averaged
(median) values for each the matrices in the slots RT, RI,
and Intensity. The values are computed only considering the masses
that correlate (the other masses are ignored). They represent an average of
RT, RI and Intensity per metabolite per sample, given that each selected mass
has their own values and often only and average is needed. These matrices are
accessed with the methods profileRT, profileRI and
profileRT.
Similar to the tsMSdata assignment methods, the
“setters” methods are exposed for convenience, though they should
not be required. The reason is that all the objects are tightly tied and
unexpected modifications could result in unintended errors. Use only if you
know what you are doing.
Objects of this class are created by the functions Profile or
ProfileCleanUp. There is no need to generate objects using
new methods.
info:"data.frame", the metabolite profile information.
See details.
RI:"list", a list of RI matrices, one matrix per
metabolite, in which rows represent select/top masses and columns
correspond to samples.
RT:"list", a list of RT matrices, one matrix per
metabolite, in which rows represent select/top masses and columns
correspond to samples.
Intensity:"list", a list of peak-intensity matrices,
one matrix per metabolite, and within each matrix, rows represent
select/top masses and columns correspond to samples.
profRI:"matrix", the profile RI matrix.
profRT:"matrix", the profile RT matrix.
profInt:"matrix", the profile Intensity matrix.
This class extends tsMSdata directly. Methods that
apply to that class apply to tsProfile.
signature(obj = "tsProfile"): get the profile information.
signature(obj = "tsProfile"): set the profile information.
signature(obj = "tsProfile"): get the profile intensity matrix.
signature(obj = "tsProfile"): set the profile intensity matrix.
signature(obj = "tsProfile"): get the profile RI matrix.
signature(obj = "tsProfile"): set the profile RI matrix.
signature(obj = "tsProfile"): get the profile RT matrix.
signature(obj = "tsProfile"): set the profile RT matrix.
signature(object = "tsProfile"): the show function.
For reasons explained in the details section, the methods profileRI<-,
profileRT<-, profileInt<-, and profileInfo are considered
deprecated and could be removed without notice in the feature.
Alvaro Cuadros-Inostroza
Profile, ProfileCleanUp, tsMSdata
showClass("tsProfile") # some example manipulations using object peakData data(TSExample) metabProfile # extract the profile information of the metabolite analysis info <- profileInfo(metabProfile) # `info` is a data.frame with the information described in details head(info) # extract profiled metabolite intensities mat <- profileInt(metabProfile) head(mat) # It is possible to use the assignment methods such as `retIndex<-`, # `Intensity<-`, `profileInt`, etc., in these objects, but it isn't # recommended. Use only if if you know what you are doing. ## Not run: profileInt(metabProfile) <- updatedMetabMatrix profileInfo(metabProfile) <- updatedMetabInfo ## End(Not run) # in the mock examples above, the objects updated* are updated data.frame or # matrices with metabolite results.showClass("tsProfile") # some example manipulations using object peakData data(TSExample) metabProfile # extract the profile information of the metabolite analysis info <- profileInfo(metabProfile) # `info` is a data.frame with the information described in details head(info) # extract profiled metabolite intensities mat <- profileInt(metabProfile) head(mat) # It is possible to use the assignment methods such as `retIndex<-`, # `Intensity<-`, `profileInt`, etc., in these objects, but it isn't # recommended. Use only if if you know what you are doing. ## Not run: profileInt(metabProfile) <- updatedMetabMatrix profileInfo(metabProfile) <- updatedMetabInfo ## End(Not run) # in the mock examples above, the objects updated* are updated data.frame or # matrices with metabolite results.
This is a class to represent retention index markers.
Objects can be created by the function ImportFameSettings or by calls
of the form new("tsRim", limits = [two column matrix with time limits],
standard = [a vector with RI standards], mass = [m/z marker]).
limits:"matrix", two column matrix with lower and upper
limits where the standards will be search. One row per standard.
standard:"numeric", the marker RI values.
mass:"numeric", the m/z marker.
[signature(x = "tsRim"): Selects a subset of markers.
rimLimitssignature(obj = "tsRim"): gets the time limits.
rimLimits<-signature(obj = "tsRim"): sets the time limits.
rimMasssignature(obj = "tsRim"): gets the m/z marker.
rimMass<-signature(obj = "tsRim"): sets the m/z marker.
rimStandardsignature(obj = "tsRim"): gets the standards.
rimStandard<-signature(obj = "tsRim"): sets the standards.
lengthReturns the number of retention index standards.
cFunction to combine multiple objects.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
showClass("tsRim") # create a rimLimit object: # - set the lower (first column) and upper (second column) time limites to # search for standards. Lim <- rbind(c(200, 300), c(400,450), c(600,650)) # - set the retention indices of the standard Std <- c(250000, 420000, 630000) # - set the mass marker mass <- 87 # - create the object rimLimits <- new("tsRim", limits = Lim, standard = Std, mass = mass) # - get the number of standards using `length` length(rimLimits) # sometimes you need to change the limits of a particular standard rimLimits(rimLimits)[2,] <- c(410, 450) # to change the mass value rimMass(rimLimits) <- 85 # to select a subset rim <- rimLimits[1:2] # remove a marker (number 3 in this case) rim <- rimLimits[-3] # objects can be combined using the `c` method obj <- new("tsRim", limits = cbind(100 * 1:6, 100 * 1:6 + 20), standard = 1000 * 1:6, mass = 100) # a random object # combine objects obj <- c(rimLimits, obj)showClass("tsRim") # create a rimLimit object: # - set the lower (first column) and upper (second column) time limites to # search for standards. Lim <- rbind(c(200, 300), c(400,450), c(600,650)) # - set the retention indices of the standard Std <- c(250000, 420000, 630000) # - set the mass marker mass <- 87 # - create the object rimLimits <- new("tsRim", limits = Lim, standard = Std, mass = mass) # - get the number of standards using `length` length(rimLimits) # sometimes you need to change the limits of a particular standard rimLimits(rimLimits)[2,] <- c(410, 450) # to change the mass value rimMass(rimLimits) <- 85 # to select a subset rim <- rimLimits[1:2] # remove a marker (number 3 in this case) rim <- rimLimits[-3] # objects can be combined using the `c` method obj <- new("tsRim", limits = cbind(100 * 1:6, 100 * 1:6 + 20), standard = 1000 * 1:6, mass = 100) # a random object # combine objects obj <- c(rimLimits, obj)
This is a class to represent a set of samples.
Objects can be created by the function ImportSamples or by calling
the object generator function.
new("tsSample", Names = [sample names], CDFfiles = [list of CDF file names],
RIfiles = [list of RI file names], CDFpath = [CDF files path],
RIpath = [RI files path], days = [measurement days],
data = [additional sample information], ftype = [RI file format])
Names:"character", the sample names.
CDFfiles:"character", the list of CDF file names.
RIfiles:"character", the list of RI file names.
CDFpath:"character", CDF files path. Deprecated. See Notes.
RIpath:"character", RI file path. Deprecated. See Notes.
days:"character", measurement days.
data:"data.frame", additional sample information.
[signature(x = "tsSample"): Selects a subset of samples.
$namesignature(x = "tsSample"): Access column name of sampleData slot.
CDFfilessignature(obj = "tsSample"): list of CDF files.
RIfilessignature(obj = "tsSample"): list of RI files.
RIpathsignature(obj = "tsSample"): The RI file path.
CDFpathsignature(obj = "tsSample"): The CDF file path.
lengthsignature(x = "tsSample"): number of samples.
sampleDatasignature(obj = "tsSample"): additional sample information.
sampleDayssignature(obj = "tsSample"): measurement days.
sampleNamessignature(obj = "tsSample"): sample names. The names must be unique
showsignature(object = "tsSample"): the show function.
fileFormatsignature(obj = "tsSample"): Sets or gets the RI file format.
Options are either "binary" or "text". See note below.
cFunction to combine multiple objects.
The method fileFormat only changes the internal information
of the file type and not the files themselves. To actually
change the files, use the functions bin2text
and text2bin.
Note that the slot Names (i.e., the sample names/identifiers) must
be unique. This allows sample selection by using sample identifiers as well
as indices. Also, if columns are selected, the output will be either a vector or
a data.frame depending on whether one or more columns were selected.
More over, it is required that the rownames of the data slot are
equal to the sample names slots. This is handled internally. If the Names
are not provided, then the CDF files are used instead (directories and
extension are removed). In this case the file names must be unique.
The slots CDFpath and RIpath are deprecated and not used.
However, the methods to set or get the paths will still work. The file
paths is stored on the CDFfiles and RIfiles slots.
The c method requires that the combination of all objects have
unique identifiers (names), or in other words, the objects cannot share
identifiers. Duplicated identifiers are not allowed and an error will be thrown.
This method also requires that the column names of the data slot
(see method sampleData) are the same, because the method calls
rbind internally.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
showClass("tsSample") # get a list of CDF files from a directory require(TargetSearchData) CDFpath <- tsd_data_path() cdffiles <- dir(CDFpath, "cdf", full=TRUE) # define the RI file path RIpath <- "." # create a tsSample object with minimal info sampleDescription <- new("tsSample", CDFfiles = cdffiles, RIpath = RIpath) ## ## ## ## ## # Alternatively, the CDF path and CDF file names can be given separately # (this was the old TargetSearch behavior) cdffiles <- basename(cdffiles) # create the sample object sampleDescription <- new("tsSample", CDFfiles = cdffiles, CDFpath = CDFpath, RIpath = RIpath) ## ## ## ## ## # More parameters could be defined: # define the RI files and the RI path RIfiles <- sub("cdf$", "txt", paste("RI_", cdffiles, sep = "")) RIpath <- "." # get the measurement days (the four first numbers of the cdf files, in this # example) days <- substring(cdffiles, 1, 4) # sample names (must be unique) smp_names <- paste("Sample", 1:length(sampleDescription), sep = "_") # add some sample info smp_data <- data.frame(CDF_FILE =cdffiles, GROUP = gl(5,3)) # create the sample object sampleDescription <- new("tsSample", Names = smp_names, CDFfiles = cdffiles, CDFpath = CDFpath, RIpath = RIpath, days = days, RIfiles = RIfiles, data = smp_data) # change the file paths (relative to the working path) CDFpath(sampleDescription) <- "my_cdfs" RIpath(sampleDescription) <- "my_RIs" # change sample Names sampleNames(sampleDescription) <- sprintf("S%03d", 1:length(sampleDescription)) ## sample subsetting. # select samples 1, 3 and 5 (sampleset <- sampleDescription[c(1, 3, 5)]) # or use sample IDs (sampleset <- sampleDescription[c("S001", "S003", "S005")]) ## extract columns # select column 'GROUP' (group <- sampleDescription$GROUP) # or (group <- sampleDescription[, 'GROUP']) ## change the measurement days (sets the same day for all samples) sampleDays(sampleDescription) <- "1" ## Note: the length of `measurement days` variable must be 1 or equal ## to the number of samples, otherwise an error will be thrown ## objects can be combined with the c() function samp1 <- sampleDescription[1:5] samp2 <- sampleDescription[6:10] samp3 <- sampleDescription[11:15] samp <- c(samp1, samp2, samp3)showClass("tsSample") # get a list of CDF files from a directory require(TargetSearchData) CDFpath <- tsd_data_path() cdffiles <- dir(CDFpath, "cdf", full=TRUE) # define the RI file path RIpath <- "." # create a tsSample object with minimal info sampleDescription <- new("tsSample", CDFfiles = cdffiles, RIpath = RIpath) ## ## ## ## ## # Alternatively, the CDF path and CDF file names can be given separately # (this was the old TargetSearch behavior) cdffiles <- basename(cdffiles) # create the sample object sampleDescription <- new("tsSample", CDFfiles = cdffiles, CDFpath = CDFpath, RIpath = RIpath) ## ## ## ## ## # More parameters could be defined: # define the RI files and the RI path RIfiles <- sub("cdf$", "txt", paste("RI_", cdffiles, sep = "")) RIpath <- "." # get the measurement days (the four first numbers of the cdf files, in this # example) days <- substring(cdffiles, 1, 4) # sample names (must be unique) smp_names <- paste("Sample", 1:length(sampleDescription), sep = "_") # add some sample info smp_data <- data.frame(CDF_FILE =cdffiles, GROUP = gl(5,3)) # create the sample object sampleDescription <- new("tsSample", Names = smp_names, CDFfiles = cdffiles, CDFpath = CDFpath, RIpath = RIpath, days = days, RIfiles = RIfiles, data = smp_data) # change the file paths (relative to the working path) CDFpath(sampleDescription) <- "my_cdfs" RIpath(sampleDescription) <- "my_RIs" # change sample Names sampleNames(sampleDescription) <- sprintf("S%03d", 1:length(sampleDescription)) ## sample subsetting. # select samples 1, 3 and 5 (sampleset <- sampleDescription[c(1, 3, 5)]) # or use sample IDs (sampleset <- sampleDescription[c("S001", "S003", "S005")]) ## extract columns # select column 'GROUP' (group <- sampleDescription$GROUP) # or (group <- sampleDescription[, 'GROUP']) ## change the measurement days (sets the same day for all samples) sampleDays(sampleDescription) <- "1" ## Note: the length of `measurement days` variable must be 1 or equal ## to the number of samples, otherwise an error will be thrown ## objects can be combined with the c() function samp1 <- sampleDescription[1:5] samp2 <- sampleDescription[6:10] samp3 <- sampleDescription[11:15] samp <- c(samp1, samp2, samp3)
tsUpdate tsUpdate is a generic function which can be used to update
and old ‘TargetSearch’ class definition. Currently, this
function is only implemented for tsSample objects.
signature(obj = "tsSample")Method to update an old tsSample object.
A change was introduced starting from ‘TargetSearch’ version 1.42.0.
Alvaro Cuadros-Inostroza
## Not run: newObject <- tsUpdate(oldObject) ## End(Not run)## Not run: newObject <- tsUpdate(oldObject) ## End(Not run)
This function can be used to correct or adjust the detected retention time
index (RI) markers or their location to specific retention times. This
function adds on fixRI() as it also corrects the RI of the CDF files
updateRI(samples, rimLimits, RImatrix = NULL, quiet = TRUE)updateRI(samples, rimLimits, RImatrix = NULL, quiet = TRUE)
samples |
A tsSample object created by ImportSamples. |
rimLimits |
A tsRim object. See ImportFameSettings. |
RImatrix |
An optional matrix. It represents a retention time matrix of the detected retention time markers that was obtained after running RIcorrect |
quiet |
Logical. Do not print a list of converted files. |
Sometimes the retention time of the RI markers are not detected correctly, either because there was a problem with the standard, or the time limits of the tsRim object were not set correctly, or simply because the markers are not injected with the samples.
In any case, the retention time correction can be fixed by calling this
function. This function works almost exactly like fixRI(), in fact, it
is called internally, and allows correction of RIfiles and CDFfiles at the
same time. Check also the documentation of fixRI() for extra details.
The parameters are the tsSample and the tsRim object, with
optionally a RImatrix to force the location of the markers. The parameter
quiet can be unset to show what samples are corrected.
If only a subset of samples require correction, then they can be chosen by
subsetting the object sample.
Neededless to say, this function expect that the CDF files exists and are
in the TargetSearch format. If this is not the case, then use the function
fixRI(), as this function deals only with RI files.
The retention index matrix. If RImatrix is not NULL, then the
output is the same matrix.
It is required that all the sample names of samples are contained in the
colnames of RImatrix, but the reverse is not necessary. The number of
columns of the output matrix will match the number of samples. Extra columns
in RImatrix will be ignored and not returned.
Alvaro Cuadros-Inostroza
fixRI(), RIcorrect(), ImportSamples(), ImportFameSettings()
require(TargetSearchData) # import refLibrary, rimLimits and sampleDescription. data(TSExample) CDFpath(sampleDescription) <- tsd_data_path() # convert a subset of files to netCDF4 smp <- ncdf4Convert(sampleDescription[1:6], path=".") # make a copy of the RI markers object fames <- rimLimits # mess up the limits of marker 3 (real value is 369 seconds app.) rimLimits(fames)[3,] <- c(375, 400) # run RIcorrect (skip CDF-4 conversion) RImat <- RIcorrect(smp, fames, Window = 15, IntThreshold = 200) # fix the limits of marker 3 rimLimits(fames)[3,] <- c(360, 380) # update RI files and CDF files RImat <- updateRI(smp, fames) # Pass a RI matrix for manual adjustment RImat[, 3] <- c(252, 311, 369) RImat <- updateRI(smp, fames, RImat) # To select specific samples, simply use sample subsetting # Note, RImat2 has only one column in this case. ( RImat2 <- updateRI(smp[3], fames, RImat) )require(TargetSearchData) # import refLibrary, rimLimits and sampleDescription. data(TSExample) CDFpath(sampleDescription) <- tsd_data_path() # convert a subset of files to netCDF4 smp <- ncdf4Convert(sampleDescription[1:6], path=".") # make a copy of the RI markers object fames <- rimLimits # mess up the limits of marker 3 (real value is 369 seconds app.) rimLimits(fames)[3,] <- c(375, 400) # run RIcorrect (skip CDF-4 conversion) RImat <- RIcorrect(smp, fames, Window = 15, IntThreshold = 200) # fix the limits of marker 3 rimLimits(fames)[3,] <- c(360, 380) # update RI files and CDF files RImat <- updateRI(smp, fames) # Pass a RI matrix for manual adjustment RImat[, 3] <- c(252, 311, 369) RImat <- updateRI(smp, fames, RImat) # To select specific samples, simply use sample subsetting # Note, RImat2 has only one column in this case. ( RImat2 <- updateRI(smp[3], fames, RImat) )
This is a convenient function to save the TargetSearch result into tab-delimited text files.
Write.Results(Lib, metabProfile, quantMatrix=c('quantmass', 'maxint', 'maxobs', 'none'), prefix = NULL, selmass = FALSE)Write.Results(Lib, metabProfile, quantMatrix=c('quantmass', 'maxint', 'maxobs', 'none'), prefix = NULL, selmass = FALSE)
Lib |
A |
metabProfile |
A |
quantMatrix |
Should an intensity matrix using quantification masses be
created? This parameter will be passed to |
prefix |
A character string. This is a file name prefix for the output
text files. If it is set to |
selmass |
Logical. This parameter is passed to the function
|
The function generates the following tab-delimited text files, where “prefix” corresponds with the selected file prefix.
prefix.peak.intensity.txt. Contains information on peak intensity
for each target mass in the library per sample.
prefix.peak.RI.txt. Contains information on retention index
(RI) for each target mass in the library per sample.
prefix.profile.info.txt. Contains the profile information for
each metabolite. See Profile and ProfileCleanUp
for details.
prefix.profile.intensities.txt. Contains information on profile
intensities per metabolite. This value is an average of all correlating
masses normalized to the mean.
prefix.profile.ri.txt. Contains information on average retention
indices of the correlating masses. This value is an average of all correlating
masses.
prefix.profile.quantmatrix.txt. The quantification matrix
as tab-delimited text file. See quantMatrix for details.
If the argument quantMatrix is equal to “none”, then this
file is not created.
The functions uses write.table as backend to write the files
with parameters set="\t" and quote=FALSE.
This function does not return anything. It just prints a message with the saved files.
Alvaro Cuadros-Inostroza, Matthew Hannah, Henning Redestig
peakFind, Profile, ProfileCleanUp,
tsLib, tsMSdata, tsProfile,
quantMatrix
# load precomputed results from `TSExample` data(TSExample) # we need the objects metabProfile and refLibrary. This will create files # with prefix 'TargetSearch-YYYY-MM-DD' corresponding to today's date Write.Results(refLibrary, metabProfile) # change the prefix with the parameter `prefix` to 'my_experiment' Write.Results(refLibrary, metabProfile, prefix='my_experiment')# load precomputed results from `TSExample` data(TSExample) # we need the objects metabProfile and refLibrary. This will create files # with prefix 'TargetSearch-YYYY-MM-DD' corresponding to today's date Write.Results(refLibrary, metabProfile) # change the prefix with the parameter `prefix` to 'my_experiment' Write.Results(refLibrary, metabProfile, prefix='my_experiment')
This function creates tab delimited text file with library information.
The created file can be re-imported with the ImportLibrary
function.
writeLibText(lib, file)writeLibText(lib, file)
lib |
A |
file |
A string naming the output file. |
Alvaro Cuadros-Inostroza
require(TargetSearchData) # get the reference library file lib.file <- tsd_file_path("library.txt") # Import the reference library refLibrary <- ImportLibrary(lib.file) # save it to a file writeLibText(refLibrary, file="libraryCopy.txt")require(TargetSearchData) # get the reference library file lib.file <- tsd_file_path("library.txt") # Import the reference library refLibrary <- ImportLibrary(lib.file) # save it to a file writeLibText(refLibrary, file="libraryCopy.txt")
This function creates MSP format file from peak intensities that can be viewed with NIST.
writeMSP(metlib, metprof, file, append = FALSE)writeMSP(metlib, metprof, file, append = FALSE)
metlib |
A |
metprof |
A |
file |
A string naming the output file. |
append |
Logical. If |
The generated file can be used to search in other library spectra using the software NIST Search Software. This software is available here (only MS Windows is supported) https://chemdata.nist.gov/dokuwiki/doku.php?id=chemdata:nistlibs
Note: the output file usually has extension .msp, which conflicts with
MS Windows Software Patch files. Care is needed to not accidentally double
click the file.
Alvaro Cuadros-Inostroza
peakFind, Profile, ProfileCleanUp,
tsLib, tsMSdata, tsProfile
# here we use precomputed objects, in particular the reference library #(refLibrary) and the metabolite profile (metabProfile). data(TSExample) # to call the function, simply use the aforementioned objects as inputs # the file 'output_file.msp' can be open in NIST Search Software writeMSP(refLibrary, metabProfile, file="output_file.msp")# here we use precomputed objects, in particular the reference library #(refLibrary) and the metabolite profile (metabProfile). data(TSExample) # to call the function, simply use the aforementioned objects as inputs # the file 'output_file.msp' can be open in NIST Search Software writeMSP(refLibrary, metabProfile, file="output_file.msp")