ume (version 1.5.2)

calc_nm: Calculate Nominal Mass of a Molecule

Description

Computes the nominal mass (integer mass) for each molecular formula in the provided data. This function uses isotope masses stored in the dataset ume::masses, based on values from NIST, for accurate calculation of each element's nominal mass contribution.

Usage

calc_nm(mfd, ...)

Value

A numeric vector of the calculated nominal mass.

Arguments

mfd

data.table with molecular formula data as derived from ume::assign_formulas. Column names of elements/isotopes must match names in the isotope column of ume::masses; values are integers representing counts per formula.

...

Additional arguments passed to methods.

Details

The function calculates the nominal mass of each molecular formula by retrieving the relevant integer mass values of isotopes from ume::masses. This information is processed to create a calculation string which is then evaluated to obtain the nominal mass for each molecule.

The nominal mass is derived by summing the integer masses of each constituent element in the formula, where the integer mass for each element is multiplied by the number of atoms of that element in the molecule.

Note: This function depends on ume::get_isotope_info() for isotope data retrieval.

See Also

Other calculations: calc_data_summary(), calc_dbe(), calc_eval_params(), calc_exact_mass(), calc_ideg(), calc_ma(), calc_neutral_mass(), calc_norm_int(), calc_number_assignment(), calc_number_occurrence(), calc_recalibrate_ms()

Examples

# Example using a demo dataset to calculate nominal mass
calc_nm(mfd = mf_data_demo)