iso_ratio {IsoCor}

iso_ratio

Description

iso_ratio will calculate a robust estimate of an isotopic ratio between intensity values of 2 mass traces.

Usage

iso_ratio(
  data = data.frame(X = rnorm(10), Y = rnorm(10)),
  method = c("PBP", "PAI", "LRS")[1],
  thr = 1
)

Arguments

data

data.frame with two columns specifying data for isotope 1 and 2 respectively.

method

Method to calculate the isotope ratio.

thr

Threshold between 0..1 to limit the peaks scans used in the calculation (1=all scans, 0=apex only).

Details

Within ic_app we compute estimates for isotope ratios using raw data and several processing steps. iso_ratio is internally used to perform this calculation and could be used in an external data processing pipeline without the app context. However, users would need to extract intensity vectors of isotope peaks from raw data independently. Note! All non-finite values and x==0 will be removed before calculation.

Value

A single numeric value. The robust ratio estimate calculated from data.

Examples

peak1 <- 1+cos(x = seq(-pi, pi, length.out=100))
peak2 <- 0.05*peak1*runif(n=100, min=1, max=1.01)
iso_ratio(data=cbind(peak1, peak2))