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FTICRMS (version 0.8)

make.par.file: Create Parameter File for FT-ICR MS Analysis

Description

Creates a file of parameters that can be read by the functions in the FTICRMS package

Usage

make.par.file(covariates, form, par.file = "parameters.RData", root.dir = ".", ...)

Arguments

covariates
data frame with rownames given by raw data files with extensions (e.g., “.txt”) stripped
form
object of class “formula” to be used for testing using covariates
par.file
string containing name of file
root.dir
string containing location for file
...
parameters whose default values are to be overwritten (see below)

Value

No value returned; the file par.file is simply created in root.dir.

Details

Creates a file with name given by par.file in directory given by root.dir which contains values for all of the parameters used in the programs in the FTICRMS package. The possible parameters that can be included in ..., their default values, their descriptions, and the program(s) in which they are used are as follows:
add.norm = TRUE
logical; whether to normalize additively or multiplicatively on the log scale run.analysis
add.par = 0 additive parameter for "shiftedlog" or "glog" options for trans.method
run.cluster.matrix, run.lrg.peaks, run.peaks align.fcn = NA
function (and inverse) to apply to masses before (and after) applying align.method run.cluster.matrix, run.strong.peaks
align.method = "spline" alignment algorithm for peaks
run.cluster.matrix, run.strong.peaks base.dir = paste(root.dir, "/Baselines", sep="")
directory for baseline files run.baselines, run.cluster.matrix, run.lrg.peaks, run.peaks
bhbysubj = FALSE logical; whether to look for number of large peaks by subject (i.e., combining replicates) or by spectrum
run.cluster.matrix, run.analysis calc.all.peaks = FALSE
logical; whether to calculate all possible peaks or only sufficiently large ones run.cluster.matrix, run.lrg.peaks, run.peaks
cluster.constant = 10 parameter used in running cluster.method
run.cluster.matrix cluster.method = "ppm"
method for determining when two peaks from different spectra are the same run.cluster.matrix
cor.thresh = 0.8 threshold correlation for declaring isotopes
run.strong.peaks FDR = 0.1
False Discovery Rate in Benjamini-Hochberg test run.analysis
FTICRMS.version = "0.8" Version of FTICRMS that created file
Archiving purposes only gengamma.quantiles = TRUE
logical; whether to use generalized gamma quantiles when calculating large peaks run.lrg.peaks, run.peaks
halve.search = FALSE logical; whether to use a halving-line search if step leads to smaller value of function
run.baselines isotope.dist = 7
maximum distance for declaring isotopes run.analysis, run.cluster.matrix, run.strong.peaks
lrg.dir = paste(root.dir, "/Large_Peaks", sep="") directory for large peaks file
run.analysis, run.cluster.matrix, run.lrg.peaks, run.strong.peaks lrg.file = "lrg_peaks.RData"
name of file for storing large peaks run.analysis, run.cluster.matrix, run.lrg.peaks, run.strong.peaks
lrg.only = TRUE logical; whether to consider only peaks that have at least one “large” peak; i.e., identified by run.lrg.peaks
run.analysis, run.cluster.matrix masses = NA
specific masses to test run.analysis, run.cluster.matrix
max.iter = 20 convergence criterion in baseline calculation
run.baselines min.spect = 1
minimum number of spectra necessary for peak to be used in run.analysis run.cluster.matrix
neg.div = NA negativity divisor in baseline calculation
run.baselines neg.norm.by = "baseline"
method for negativity penalty in baseline analysis run.baselines
norm.peaks = "common" which peaks to use in normalization
run.analysis norm.post.repl = FALSE
logical; whether to normalize after combining replicates run.analysis
num.pts = 5 number of consecutive points needed for peak fitting
run.cluster.matrix, run.peaks oneside.min = 1
minimum number of points on each side of local maximum for peak fitting run.cluster.matrix, run.peaks
overwrite = FALSE logical; whether to replace existing files with new ones
All six programs par.file = "parameters.RData"
string containing name of parameters file All six programs
peak.dir = paste(root.dir, "/All_Peaks", sep="") directory for peak location files
run.cluster.matrix, run.lrg.peaks, run.peaks peak.method = "parabola"
method for locating peaks run.cluster.matrix, run.peaks
peak.thresh = 3.798194 threshold for declaring large peak
run.lrg.peaks, run.peaks pre.align = FALSE
shifts to apply before running run.strong.peaks run.cluster.matrix, run.strong.peaks
pval.fcn = "default" function to calculate p-values; default is overall p-value of test
run.analysis R2.thresh = 0.98
$R^2$ value needed for peak fitting run.cluster.matrix, run.peaks
raw.dir = paste(root.dir, "/Raw_Data", sep="") directory for raw data files
run.baselines rel.conv.crit = TRUE
whether convergence criterion should be relative to size of current baseline estimate run.baselines
repl.method = "max" how to deal with replicates
run.analysis res.dir = paste(root.dir, "/Results", sep="")
directory for results file run.analysis
res.file = "analyzed.RData" name for results file
run.analysis root.dir = "."
directory for parameters file and raw data All six programs
sm.div = NA smoothness divisor in baseline calculation
run.baselines sm.norm.by = "baseline"
method for smoothness penalty in baseline analysis run.baselines
sm.ord = 2 order of derivative to penalize in baseline analysis
run.baselines sm.par = 1e-11
smoothing parameter for baseline calculation run.baselines
subs subset of spectra to use for analysis
run.lrg.peaks, run.analysis subtract.base = FALSE
logical; whether to subtract calculated baseline from spectrum run.cluster.matrix, run.lrg.peaks, run.peaks
tol = 5e-8 convergence criterion in baseline calculation
run.baselines trans.method = "shiftedlog"
data transformation method run.cluster.matrix, run.lrg.peaks, run.peaks
use.model = "lm" what model to apply to data
run.analysis zero.rm = TRUE
whether to replace zeros in spectra with average of surrounding values run.baselines

References

Barkauskas, D.A. and D.M. Rocke. (2009a) “A general-purpose baseline estimation algorithm for spectroscopic data”. to appear in Analytica Chimica Acta. doi:10.1016/j.aca.2009.10.043

Barkauskas, D.A. et al. (2009b) “Analysis of MALDI FT-ICR mass spectrometry data: A time series approach”. Analytica Chimica Acta, 648:2, 207--214.

Barkauskas, D.A. et al. (2009c) “Detecting glycan cancer biomarkers in serum samples using MALDI FT-ICR mass spectrometry data”. Bioinformatics, 25:2, 251--257.

Xi, Y. and Rocke, D.M. (2008) “Baseline Correction for NMR Spectroscopic Metabolomics Data Analysis”. BMC Bioiniformatics, 9:324.

See Also

extract.pars