iwNormQE.5 {msPurity} | R Documentation

## Q-Exactive +/- 0.5 range, normalisation for isolation window efficiency

### Description

Creates a function based on a previous experimental analysis of a Q-Exactive at +/- 0.5 isolation window efficiency. See http://pubs.acs.org/doi/abs/10.1021/acs.analchem.6b04358

The function that is created will output a value between 0 to 1 based on the position between the minOff and maxOff params

NOTE: The resulting function will work for values greater that 0.5 and less than -0.5.

This is because (on our instrument tested at least) when using a window of +/- 0.5, the isolation is NOT confined to the +/-0.5 Da window. Resulting in ions from outside the window being isolated. For this reason the function can normalise values outside of the the +/- 1 Da range. Please see above paper figure 3 for more details.

### Usage

    iwNormQE.5()

### Value

normalisation function for +/- 0.5 range for Q-Exactive

### Examples

    iwNormFun <- iwNormQE.5()
    pm <- data.frame(mz=c(99.5, 99.9, 100, 100.1, 100.5),i=c(1000, 1000, 1000, 1000, 1000))
    mzmax = 100.5
    mzmin = 99.5
    middle <- mzmax-(mzmax-mzmin)/2
    adjustmz = pm$mz-middle

    # normalise the intensities
    pm$normi = pm$i*iwNormFun(adjustmz)

[Package msPurity version 1.18.0 Index]