def note_number_to_hz(note_number):
    # MIDI note numbers are defined as the number of semitones relative to C0
    # in a 440 Hz tuning
    return 440.0*(2.0**((note_number - 69)/12.0))
Convert a (fractional) MIDI note number to its frequency in Hz.
dataset/ETHPy150Open craffel/pretty-midi/pretty_midi/utilities.py/note_number_to_hz