There's also a huge pile of chord charts published online for the jazz standards and the Great American Songbook, that would be interesting to analyze.
Can't resist mentioning that old joke : "A pop guitarist plays five chords for ten thousand people, a jazz guitarist plays ten thousand chords for five people"
I've kind of lost touch. My "fake books" were all hand written and photocopied.
Even the better players were becoming so dependent on them, that it was detracting from the music, so I went cold turkey and learned the tunes.
An app called "iRealPro" has chord changes in a strange format, and somebody once created a Python library to decode it.
There was once a book called "pocket changes" with just chord changes, and I think it was converted to text format, but can't find it anywhere online. The changes are an outgrowth of a quirk in the copyright law, where the melody and words can be copyrighted, but not the harmony.
Some of the chord charts are machine readable (available as just plain text), while others are images, but looks like all/almost all of them are available as MIDI as well.
