## ----setup, include=FALSE, cache=FALSE---------------------------------------- library("knitr") opts_chunk$set(tidy.opts=list(width.cutoff=45), tidy=FALSE, fig.align="center", fig.height=4.25, comment=NA, prompt=TRUE) ## ----env, echo=FALSE---------------------------------------------------------- suppressPackageStartupMessages(library("MALDIquant")) ## ----mqsetup, eval=FALSE------------------------------------------------------ # install.packages(c("MALDIquant", "MALDIquantForeign")) ## ----mqlibrary, eval=FALSE---------------------------------------------------- # library("MALDIquant") ## ----mqobjects---------------------------------------------------------------- s <- createMassSpectrum(mass=1:10, intensity=1:10, metaData=list(name="Spectrum1")) s ## ----mqaccess----------------------------------------------------------------- mass(s) intensity(s) metaData(s) ## ----mqdataimport------------------------------------------------------------- data(fiedler2009subset) ## ----mqdataimport2------------------------------------------------------------ length(fiedler2009subset) fiedler2009subset[1:2] ## ----mqqclength--------------------------------------------------------------- any(sapply(fiedler2009subset, isEmpty)) table(sapply(fiedler2009subset, length)) ## ----mqqcregular-------------------------------------------------------------- all(sapply(fiedler2009subset, isRegular)) ## ----mqqcplots---------------------------------------------------------------- plot(fiedler2009subset[[1]]) plot(fiedler2009subset[[16]]) ## ----mqvs--------------------------------------------------------------------- spectra <- transformIntensity(fiedler2009subset, method="sqrt") ## ----mqsm--------------------------------------------------------------------- spectra <- smoothIntensity(spectra, method="SavitzkyGolay", halfWindowSize=10) ## ----mqve--------------------------------------------------------------------- baseline <- estimateBaseline(spectra[[16]], method="SNIP", iterations=100) plot(spectra[[16]]) lines(baseline, col="red", lwd=2) ## ----mqbc--------------------------------------------------------------------- spectra <- removeBaseline(spectra, method="SNIP", iterations=100) plot(spectra[[1]]) ## ----mqcb--------------------------------------------------------------------- spectra <- calibrateIntensity(spectra, method="TIC") ## ----mqpa--------------------------------------------------------------------- spectra <- alignSpectra(spectra, halfWindowSize=20, SNR=2, tolerance=0.002, warpingMethod="lowess") ## ----mqav1-------------------------------------------------------------------- samples <- factor(sapply(spectra, function(x)metaData(x)$sampleName)) ## ----mqav2-------------------------------------------------------------------- avgSpectra <- averageMassSpectra(spectra, labels=samples, method="mean") ## ----mqpd1-------------------------------------------------------------------- noise <- estimateNoise(avgSpectra[[1]]) plot(avgSpectra[[1]], xlim=c(4000, 5000), ylim=c(0, 0.002)) lines(noise, col="red") lines(noise[,1], noise[, 2]*2, col="blue") ## ----mqpd2-------------------------------------------------------------------- peaks <- detectPeaks(avgSpectra, method="MAD", halfWindowSize=20, SNR=2) plot(avgSpectra[[1]], xlim=c(4000, 5000), ylim=c(0, 0.002)) points(peaks[[1]], col="red", pch=4) ## ----mqpb--------------------------------------------------------------------- peaks <- binPeaks(peaks, tolerance=0.002) ## ----mqfp--------------------------------------------------------------------- peaks <- filterPeaks(peaks, minFrequency=0.25) ## ----mqim--------------------------------------------------------------------- featureMatrix <- intensityMatrix(peaks, avgSpectra) head(featureMatrix[, 1:3]) ## ----sessioninfo, echo=FALSE, results="asis"---------------------------------- toLatex(sessionInfo(), locale=FALSE)