Learn R Programming

rtmsEcho (version 0.2.4)

getMRMAreas: Extract the peak areas for MRM mass transitions for a given well

Description

Extract the peak areas for MRM mass transitions for a given well

Usage

getMRMAreas(scanfile, tic, sample, ejections, well, removeBaseline = TRUE)

Value

A data frame containing the total intensity for each mass transition and each ejection; see Details for column specifics.

Arguments

scanfile

A file path to a Sciex raw scan file (extension .wiff.scan) containing the raw data referenced by the .wiff file from which the other parameters were extracted

tic

A total ion chromatogram data.frame as extracted by getTIC() or getAllTIC()

sample

A "sample" object representing a run in a .wiff file, from the samples field of an rtmsWiffReader object, containing information about the mass transitions measured in that run

ejections

An ejection table listing the timing and boundaries of the total ion chromatogram peaks for all shots in the run, as returned by measureEjections()

well

The well (a string) or well index (an integer) to be measured

removeBaseline

If TRUE, baseline intensity for each mass transition will be subtracted from the intensities in each ejection, to account for baseline intensities measured near the lower limit of quantitation

Details

The table return includes a measurement of total area for each of the mass transitions listed in sample. It contains one row for each measured shot each mass transition, with the following columns:

  • shotorder: The order of the peak within the shots fired during the run

  • well: The alphanumeric well name of the well from which the shot was fired

  • time: The time (in seconds) after the beginning of the run at which the intensity from the shot was at its peak

  • massindex: The index of the measured mass transition in the set of masses in the given sample

  • mass: The name of the mass transition measured (often a compound name or id)

  • area: The intensity area (in counts) for that particular mass transition from that shot's peak