matchms.filtering.peak_processing.reduce_to_number_of_peaks module

matchms.filtering.peak_processing.reduce_to_number_of_peaks.reduce_to_number_of_peaks(spectrum_in: Spectrum, n_required: int = 0, n_max: int = inf, ratio_desired: float | None = None) → Spectrum[source]

Lowest intensity peaks will be removed when it has more peaks than desired.

Parameters:

  • spectrum_in – Input spectrum.

  • n_required – Number of minimum required peaks. Spectra with fewer peaks will be set to ‘None’. Default is 1.

  • n_max – Maximum number of peaks. Remove peaks if more peaks are found. Default is inf.

  • ratio_desired – Set desired ratio between maximum number of peaks and parent mass. For spectra without parent mass (e.g. GCMS spectra) this will raise an error when ratio_desired is used. Default is None.