Transposing chords from one key to another
To transpose chords, use transposer like this:
python transposer.py --from=F# --to=Eb input.txt
The input file should be a plain text file, but can contain any text - only lines starting with a vertical bar (|) will be transposed. On these lines, root notes must be in upper case while everything else should be in lower case.
The contents of example.txt:
Rocking start, jazzy ending
| D | G A | Bbm7#11/Db |
Using transposer --from=D --to=E example.txt will produce the result
Result (D -> E):
Rocking start, jazzy ending
| E | A B | Cm7#11/D# |
Run unit tests using Python's doctest:
python -m doctest -v transposer.py