Expand description
A score reduced to the chords it is made of: music21’s
analysis.reduceChords.
reduce_chords is music21’s ChordReducer.run. It reads the score’s
notes as spans of time – a part, a stretch, and the notes sounding in
it – and then thins them out: a span of no length goes, the spans of
each part are fused where they sound the same notes in one measure, they
are cut at every offset the bass moves, the notes above the bass of a
dissonant moment go, the gaps the thinning leaves are filled, and spans
shorter than half a note and then shorter than a note go unless they
fill their measure. What is left is chordified against the score, and
each measure is reduced to the few chords weighing most in it.
The weight of a chord is music21’s qlbsmpConsonance: how long it
sounds, times how strong its beat is, times a tenth if it is dissonant,
with the last chord of a measure counted as if it stood on the
downbeat.
Structs§
- Reduction
Options - What a reduction is asked for: music21’s arguments to
ChordReducer.run.
Functions§
- reduce_
chords - A score reduced to its chords: music21’s
ChordReducer.run, which hands back a score of one part.