IsoSpec is a fine structure calculator used for obtaining the most probable masses of a chemical compound given the frequencies of the composing isotopes and their masses. It finds the smallest set of isotopologues with a given probability. The probability is assumed to be that of the product of multinomial distributions, each corresponding to one particular element and parametrized by the frequencies of finding these elements in nature. These numbers are supplied by IUPAC  the International Union of Pure and Applied Chemistry.
Package details 


Author  Mateusz Krzysztof Lacki and Michal Startek 
Maintainer  Matteo Lacki <[email protected]> 
License  BSD_2_clause + file LICENCE 
Version  1.9.2 
URL  http://matteolacki.github.io/IsoSpec/ 
Package repository  View on CRAN 
Installation 
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