inst/comparison.md

In nathaniel-mahieu/centWaveP: CWT Based Chromatographic Peak Detection

xcms::findPeaks.centWave vs centWaveP

library(centWaveP)
library(xcms)
library(gridExtra)

centWaveP

file = "../../../Projects/Datasets/2nm118a_nh2_negative_ecoli_1213/2NM118A_HILICAnnoWgN14_2NM111G_12.mzXML"

xr = xcmsRaw(file, profstep=0)

roi.l = cent.xr(xr, ppm = 2, prefilter = c(4,0), maxskip = 5) # ppm is added to both sides

##  % finished: 0 10 20 30 40 50 60 70 80 90 100 
##  252768 m/z ROI's.

eic.l = lapply(sample(roi.l, 3000), roiToEic, xr, padding=100)
eic.noise.l = lapply(eic.l, estimateBaselineNoise, peakwidth = c(15, 60), minslope.peak = 20000)

peaks = lapply(seq_along(eic.noise.l), function(i) {
  wave(eic.noise.l[[i]], peakwidth = c(15, 70), valleywidth.min = 15, sensitivity = 1, smooth = T)
})

index = lapply(seq(peaks), function(i) {
  wns = peaks[[i]]$descent.fold.above.descentbaseline
  cbind(roi = rep(i, length(wns)), wsn = wns, num = seq_along(wns))
  }) %>% do.call(what = rbind)

nrow(index)

## [1] 136

SN < 1

ps0 = lapply(sample(which(index[,"wsn"] < 1), 16, replace = T), function(x) {
  plotWavePeak(unname(index[x, "num"]), eic.noise.l[[index[x,"roi"]]], peaks[[index[x,"roi"]]])
})
do.call(grid.arrange, ps0)  

1 < SN < 2

ps1 = lapply(sample(index[,"wsn"] %>% { which(. > 1  & . < 2) }, 16, replace = T), function(x) {
  plotWavePeak(unname(index[x, "num"]), eic.noise.l[[index[x,"roi"]]], peaks[[index[x,"roi"]]])
})
do.call(grid.arrange, ps1)  

2 < SN < 3

ps2 = lapply(sample(index[,"wsn"] %>% { which(. > 2  & . < 3) }, 16, replace = T), function(x) {
  plotWavePeak(unname(index[x, "num"]), eic.noise.l[[index[x,"roi"]]], peaks[[index[x,"roi"]]])
})
do.call(grid.arrange, ps2)

3 < SN < 4

ps3 = lapply(sample(index[,"wsn"] %>% { which(. > 3  & . < 5) }, 16, replace = T), function(x) {
  plotWavePeak(unname(index[x, "num"]), eic.noise.l[[index[x,"roi"]]], peaks[[index[x,"roi"]]])
})
do.call(grid.arrange, ps3)

5 < SN

ps4 = lapply(sample(index[,"wsn"] %>% { which(. > 5) }, 16, replace=T), function(x) {
  plotWavePeak(unname(index[x, "num"]), eic.noise.l[[index[x,"roi"]]], peaks[[index[x,"roi"]]])
})
do.call(grid.arrange, ps4)

xcms::findPeaks.centWave

ROI.list = xcms:::findmzROI(xr, dev = 2*1E-6, minCentroids = 4, prefilter = c(4,0), noise = 0)

##  % finished: 0 10 20 30 40 50 60 70 80 90 100 
##  319716 m/z ROI's.

peaks.xcms = findPeaks.centWave(xr, ppm = 2, peakwidth = c(15, 60), snthresh = 0, prefilter = c(4,0), noise = 0, ROI.list = sample(ROI.list, 3000))

## 
##  Detecting chromatographic peaks ... 
##  % finished: 0 10 20 30 40 50 60 70 80 90 100 
##  441  Peaks.

nrow(peaks.xcms)

## [1] 441

head(peaks.xcms)

##            mz    mzmin    mzmax       rt    rtmin    rtmax      into
## [1,] 612.8240 612.8233 612.8246  962.053  954.758  967.675 1594222.6
## [2,] 207.0390 207.0389 207.0394  129.254  122.483  137.122  799475.6
## [3,] 328.1153 328.1151 328.1157 2000.120 1984.260 2011.440 8815864.7
## [4,] 328.1153 328.1151 328.1157 2000.120 1984.260 2011.440 8815864.7
## [5,] 544.3498 544.3492 544.3505 1243.640 1242.510 1282.070 4271358.7
## [6,] 544.3495 544.3488 544.3503 1179.240 1178.670 1179.800  207298.2
##           intb     maxo     sn
## [1,] 1594210.2 221493.9 221493
## [2,]  786179.0 155846.3     12
## [3,] 8815837.5 777535.7 777535
## [4,] 8815837.5 777535.7 777535
## [5,] 3195635.5 154251.5      5
## [6,]  159851.8 135370.6      6

1 < SN < 5

 ps4 = lapply(sample(peaks.xcms[,"sn"] %>% { which(. > 1 & . < 5) }, 16, replace=T), function(i) {
   scrange = c(peaks.xcms[i,"rtmin"]-30, peaks.xcms[i,"rtmax"]+30)
   scrange[scrange < 1] = 1; scrange[scrange > max(xr@scantime)] = max(xr@scantime)
    eic = rawEIC(xr, mzrange = c(peaks.xcms[i,"mzmin"], peaks.xcms[i,"mzmax"]), rtrange = scrange)

    df = data.frame(eic)

    ggplot(df) +
      geom_line(aes(x = scan, y = intensity))
   })
do.call(grid.arrange, ps4)

5 < SN < 10

 ps4 = lapply(sample(peaks.xcms[,"sn"] %>% { which(. > 5 & . < 10) }, 16, replace=T), function(i) {
   scrange = c(peaks.xcms[i,"rtmin"]-30, peaks.xcms[i,"rtmax"]+30)
   scrange[scrange < 1] = 1; scrange[scrange > max(xr@scantime)] = max(xr@scantime)
    eic = rawEIC(xr, mzrange = c(peaks.xcms[i,"mzmin"], peaks.xcms[i,"mzmax"]), rtrange = scrange)

    df = data.frame(eic)

    ggplot(df) +
      geom_line(aes(x = scan, y = intensity))
   })
do.call(grid.arrange, ps4)

10 < SN < 100

 ps4 = lapply(sample(peaks.xcms[,"sn"] %>% { which(. > 10 & . < 100) }, 16, replace=T), function(i) {
   scrange = c(peaks.xcms[i,"rtmin"]-30, peaks.xcms[i,"rtmax"]+30)
   scrange[scrange < 1] = 1; scrange[scrange > max(xr@scantime)] = max(xr@scantime)
    eic = rawEIC(xr, mzrange = c(peaks.xcms[i,"mzmin"], peaks.xcms[i,"mzmax"]), rtrange = scrange)

    df = data.frame(eic)

    ggplot(df) +
      geom_line(aes(x = scan, y = intensity))
   })
do.call(grid.arrange, ps4)

SN > 100

 ps4 = lapply(sample(peaks.xcms[,"sn"] %>% { which(. > 100) }, 16, replace=T), function(i) {
   scrange = c(peaks.xcms[i,"rtmin"]-30, peaks.xcms[i,"rtmax"]+30)
   scrange[scrange < 1] = 1; scrange[scrange > max(xr@scantime)] = max(xr@scantime)
    eic = rawEIC(xr, mzrange = c(peaks.xcms[i,"mzmin"], peaks.xcms[i,"mzmax"]), rtrange = scrange)

    df = data.frame(eic)

    ggplot(df) +
      geom_line(aes(x = scan, y = intensity))
   })
do.call(grid.arrange, ps4)

nathaniel-mahieu/centWaveP documentation built on May 23, 2019, 12:19 p.m.