Module pitch

Expand description

Pitch construction, spelling and pitch-space helpers.

Structs§

Accidental: Symbolic and numerical accidental information for a pitch.
AccidentalDisplayOptions: The context music21’s updateAccidentalDisplay reads: the pitches that came before, in this measure and the previous one, the other pitches sounding at the same time, the key signature’s altered pitches, and the cautionary-accidental switches, with music21’s defaults.
Microtone: A microtonal pitch adjustment measured in cents, optionally shifted by a harmonic like Python music21’s music21.pitch.Microtone.
Pitch: A musical pitch with spelling, octave, accidental and optional microtone.
PitchClass: A normalized pitch-class value.
PitchOptions: Builder options for constructing a Pitch.

AccidentalAttribute: One part of an Accidental, for Accidental::set_attribute_independently. music21 names the part with a string and raises on any other name; here the three writable parts are the only ones that can be spelled.
AccidentalSpecifier: Input accepted by Accidental::new and Accidental::set.
MicrotoneSpecifier: Input accepted by Microtone::new and Microtone::with_harmonic_shift.
PitchClassSpecifier: Input accepted by PitchClass::new and pitch-class builders.
PitchName: Input accepted as a pitch name or pitch-space number.

CHROMATIC_PITCH_CLASS_NAMES: Canonical pitch names for chromatic pitch classes.

convert_pitch_class_to_str: music21’s convertPitchClassToStr: an integer pitch class as one character, A for ten and B for eleven, reduced modulo twelve first.
dissonance_score: How awkward a set of pitches reads together: music21’s _dissonanceScore with all three of its terms on. It averages a penalty for accidentals beyond one sharp or flat, a penalty growing with the denominator of each pair’s Pythagorean ratio, and a reward for every third and sixth, so that C E G scores below C F- G.
pitch_class_name: Returns a canonical pitch name for a chromatic pitch class.
simplify_multiple_enharmonics: Respells a set of pitches so that they read as simply as possible together: music21’s simplifyMultipleEnharmonics. The first pitch is kept as written and each of the others may be swapped for a common enharmonic; the spelling chosen is the one the criterion scores lowest, by default dissonance_score. Up to four pitches are searched exhaustively, more are settled greedily one at a time, as upstream does. With a key signature the tonic of its major key is placed first as an anchor and removed again afterwards.

CriterionFunction: A scoring function for simplify_multiple_enharmonics: lower is a simpler spelling.