Convert a series of notes into frequency

sheet_to_freq.py

"""
Note To Frequency Converter
MIT License 2022

Inspired by stuartmemo's JavaScript version

See https://gist.github.com/stuartmemo/3766449 for more info and this gist in more languages

"""

NOTES = ('a', 'a#', 'b', 'c', 'c#', 'd', 'd#', 'e', 'f', 'f#', 'g', 'g#')

def freq(note):
    if len(note) == 3:
        octave = int(note[2])
    else:
        octave = int(note[1])

    key_no = NOTES.index(note[:-1])

    if key_no < 3:
        key_no = key_no + 12 + ((octave - 1) * 12) + 1
    else:
        key_no = key_no + ((octave - 1) * 12) + 1

    return 440 * (2 ** ((key_no - 49) / 12))

# Test
print(freq('a4'))

# Actual - change the BPM to alter duration, or assign duration values yourself. The time shown below is in seconds.
bpm = 90.0
quad_dur = round(60.0 / bpm, 3)
eighth_dur = round(quad_dur / 2.0, 3)
sixteenth_dur = round(eighth_dur / 2.0, 3)

# If using Assembly, this may also come in handy.
# eighth_dur = 2
# sixteenth_dur = 1

# Transcribe your notes in here
sheet = [
    ('d#5', eighth_dur),
    ('d5', eighth_dur),
    ('a#5', eighth_dur),
    ('a5', sixteenth_dur),
    ('g5', sixteenth_dur),
    ('f#5', eighth_dur),
    ('g5', eighth_dur),
    ('a5', eighth_dur),
    ('c5', eighth_dur),

    ('d#5', eighth_dur),
    ('d5', eighth_dur),
    ('c6', eighth_dur),
    ('a#5', sixteenth_dur),
    ('a5', sixteenth_dur),
    ('g5', eighth_dur),
    ('a5', eighth_dur),
    ('a#5', eighth_dur),
    ('e5', eighth_dur),

    ('g5', eighth_dur),
    ('a5', eighth_dur),
    ('a#5', eighth_dur),
    ('e5', eighth_dur),
    ('g5', eighth_dur),
    ('a5', eighth_dur),
    ('a#5', eighth_dur),
    ('e6', eighth_dur),

    ('d6', eighth_dur),
    ('d6', eighth_dur),
    ('c6', eighth_dur),
    ('c6', eighth_dur),
    ('a#5', eighth_dur),
    ('a#5', eighth_dur),
    ('a5', eighth_dur),
    ('a#4', eighth_dur),

    ('d#5', eighth_dur),
    ('d5', eighth_dur),
    ('a#5', eighth_dur),
    ('a5', sixteenth_dur),
    ('g5', sixteenth_dur),
    ('f#5', eighth_dur),
    ('g5', eighth_dur),
    ('a5', eighth_dur),
    ('c5', eighth_dur),

    ('d#5', eighth_dur),
    ('d5', eighth_dur),
    ('c6', eighth_dur),
    ('a#5', sixteenth_dur),
    ('a5', sixteenth_dur),
    ('g5', eighth_dur),
    ('a5', eighth_dur),
    ('a#5', eighth_dur),
    ('e5', eighth_dur),

    ('g5', eighth_dur),
    ('a5', eighth_dur),
    ('a#5', eighth_dur),
    ('e5', eighth_dur),
    ('f5', eighth_dur),
    ('f#5', eighth_dur),
    ('g5', eighth_dur),
    ('e6', eighth_dur),

    ('d6', eighth_dur),
    ('d6', eighth_dur),
    ('c6', eighth_dur),
    ('c6', eighth_dur),
    ('a#5', eighth_dur),
    ('a#5', eighth_dur),
    ('a5', eighth_dur),
    ('a#4', eighth_dur)
]

# This export format is for Assembly specifially. You may write your own version if you need.
def export(sheet):
    lines = ['FREQ_L\tDW\t']
    first_note = True

    for note, dur in sheet:
        f = freq(note)
        if len(lines[-1] + f', {int(f)}, {dur}') > 80:
            lines.append(f'\tDW\t{int(f)}, {dur}')
        else:
            if not first_note:
                lines[-1] += ', '
            else:
                first_note = False
            lines[-1] += f'{int(f)}, {dur}'

    return '\n'.join(lines)

if __name__ == '__main__':
    export(sheet)