2-point correction of RIs

correctRindex performs correction of retention indices (RIs) based on reference substances. Even after conversion of RTs to RIs slight deviations might exist. These deviations can be further normalized, if they are linear, by using two metabolites for which the RIs are known (e.g. internal standards).

Usage

correctRindex(x, y)

Arguments

x

numeric vector with retention indices, calculated by indexRtime

y

data.frame containing two columns. The first is expected to contain the measured RIs of the reference substances and the second the reference RIs.

Value

numeric vector of same length than x with corrected retention indices. Values are floating point decimals. If integer values shall be used conversion has to be performed manually.

Author

Michael Witting

Examples

ref <- data.frame(rindex = c(110, 210),
refindex = c(100, 200))
rindex <- c(110, 210)
correctRindex(rindex, ref)
#> [1] 100 200