calculateNrPeaks {BRAIN} | R Documentation

## Function computing heuristically the required number of consecutive aggregated isotopic variants.

### Description

Function computing heuristically the required number of consecutive aggregated isotopic variants (starting from the monoisotopic mass).

### Usage

    calculateNrPeaks(aC)

### Arguments

`aC` | List with fields C, H, N, O, S of integer non-negative values (if any field is ommited, then its value is set to 0).

### Details

This function uses following rule of thumb: the difference between the theoretical monoisotopic mass and the theoretical average mass is computed and multiplied by two. Subsequently, the obtained number is rounded to the nearest integer greater than or equal to the multiplied difference. For small molecules, the minimal number of returned variants is five.

### Value

Integer number not lower than 5.

### Author(s)

Jurgen Claesen <jurgen.claesen@uhasselt.be>

### References

[Clae] Claesen J., Dittwald P., Burzykowski T. and Valkenborg D. An efficient method to calculate the aggregated isotopic distribution and exact center-masses. JASMS, 2012, doi:10.1007/s13361-011-0326-2

### See Also

`useBRAIN`

### Examples

      aC <-  list(C=23832, H=37816, N=6528, O=7031, S=170)  # Human dynein heavy chain
      res <- calculateNrPeaks(aC = aC)

[Package BRAIN version 1.40.0 Index]