ppm: Calculate ppm values

In RMassBank: Workflow to process tandem MS files and build MassBank records

Description

Calculates ppm values for a given mass.

Usage

ppm(mass, dppm, l = FALSE, p = FALSE)

Arguments

mass	The "real" mass
dppm	The mass deviation to calculate
l	Boolean: return limits? Defaults to FALSE.
p	Boolean: return ppm error itself? Defaults to FALSE.

Details

This is a helper function used in RMassBank code.

Value

By default (l=FALSE, p=FALSE) the function returns the mass plus the ppm error (for 123.00000 and 10 ppm: 123.00123, or for 123 and -10 ppm: 122.99877).

For l=TRUE, the function returns the upper and lower limit (sic!) For p=TRUE, just the difference itself is returned (0.00123 for 123/10ppm).

Author(s)

Michael A. Stravs, Eawag <[e-mail]>

Examples

ppm(100, 10)

RMassBank documentation built on Nov. 8, 2020, 6:06 p.m.