recMID {CorMID}R Documentation

recMID.

Description

recMID will reconstruct a measured GC-APCI-MS spectrum of a compound given its true MID and the fragment ratio.

Usage

recMID(
  mid = c(1, 0, 0),
  r = list(`M+H` = 1),
  fml = NULL,
  cutoff = 0.001,
  algo = c("CorMID", "Rdisop")
)

## S3 method for class 'recMID'
plot(x, ...)

Arguments

mid

A numeric vector with sum=1 and length of C atoms +1.

r

Fragment ratios. A numeric vector with sum=1.

fml

A compound formula.

cutoff

Remove values below this threshold from output vector.

algo

The algorithm used to estimate the isotopic distribution of a chemical formula.

x

Object of class recMID.

...

Further plotting parameters.

Details

recMID is basically the inverse function to CorMID. Providing a specific chemical formula together with information regarding the true MID and r, this function will compute a vector of ion intensities which can be expected in a GC-APCI-MS analysis for this compound.

Value

A reconstructed MID, i.e. the relative intensity values that would be measured for the specified molecule 'fml' with respect to parameters“mid' and 'r'. The default values for 'mid' and 'r' are set to reflect natural abundance and no fragmentation.

Examples

fml <- "C9H20O3Si2"
mid <- c(0.9,0,0,0.1)
r <- list("M+H"=0.8, "M-H"=0.1, "M+H2O-CH4"=0.1)
(rMID <- CorMID::recMID(mid=mid, r=r, fml=fml))
plot(rMID)
plot(x = rMID, ylim=c(0,max(rMID)))
plot(x = rMID, xlim=c(-2,12), ylim=NULL, col=2, lwd=12, las=2, xlab="label")

CorMID::CorMID(int = rMID, fml=fml, prec=0.001, r=unlist(r), trace_steps = TRUE)


[Package CorMID version 0.3.1 Index]