Music scale manipulation

scales.py

#!/usr/bin/python

# Transpose the deltas so that the first one is 0 and everything is in [0, 12).
def normalize(deltas):
    root = deltas[0] % 12
    return [(delta + 12 - root) % 12 for delta in deltas]

def transpose(deltas, base):
    return [(delta + base) % 12 for delta in deltas]

# Gives the list of notes for the deltas using base as the base note
# (0=C, 1=Db, 2=D, ...)
# Two variants are available, one where only flats (and naturals) are used and 
# another where only sharps are used.
def notes(deltas, base, sharp):
    table = deltaToNoteSharp if sharp else deltaToNoteFlat
    return [table[(delta + base) % 12] for delta in deltas]
deltaToNoteFlat = ['C', 'Db', 'D', 'Eb', 'E', 'F', 'Gb', 'G', 'Ab', 'A', 'Bb', 'B']
deltaToNoteSharp = ['B#', 'C#','D', 'D#', 'E', 'F', 'F#', 'G', 'G#', 'A', 'A#', 'B']

# major pentatonic
keysMaj = normalize([1, 3, 5, 8, 10])

# minor pentatonic
keysMin = normalize([1, 4, 6, 8, 11])

print keysMaj

# C maj pentatonic
print notes(keysMaj, 0, False)
# A min pentatonic
print notes(keysMin, 9, False)