13. Pitches¶
Named chromatic pitches are the everyday pitches attached to notes and chords:
abjad> note = Note("cs''8")
abjad> note.written_pitch
NamedChromaticPitch("cs''")
13.1. Creating pitches¶
Use pitch tools to create named chromatic pitches:
abjad> named_chromatic_pitch = pitchtools.NamedChromaticPitch("cs''")
abjad> named_chromatic_pitch
NamedChromaticPitch("cs''")
13.2. Inspecting the name of a pitch¶
Use str() to get the name of named chromatic pitches:
abjad> str(named_chromatic_pitch)
cs''
13.3. Inspecting the octave of a pitch¶
Get the octave number of named chromatic pitches with octave_number:
abjad> named_chromatic_pitch.octave_number
5
13.4. Working with pitch deviation¶
Use deviation to model the fact that two pitches differ by a fraction of a semitone:
abjad> note_1 = Note(24, (1, 2))
abjad> note_2 = Note(24, (1, 2))
abjad> staff = Staff([note_1, note_2])
abjad> show(staff)
abjad> note_2.written_pitch = pitchtools.NamedChromaticPitch(24, deviation = -31)
The pitch of the the first note is greater than the pitch of the second:
abjad> note_1.written_pitch > note_2.written_pitch
True
Use markup to include indications of pitch deviation in your score:
abjad> markuptools.Markup(note_2.written_pitch.deviation_in_cents, 'up')(note_2)
13.5. Sorting pitches¶
Named chromatic pitches sort by octave, diatonic pitch-class and accidental, in that order:
abjad> pitchtools.NamedChromaticPitch('es') < pitchtools.NamedChromaticPitch('ff')
True
13.6. Comparing pitches¶
Compare named chromatic pitches to each other:
abjad> named_chromatic_pitch_1 = pitchtools.NamedChromaticPitch("c''")
abjad> named_chromatic_pitch_2 = pitchtools.NamedChromaticPitch("d''")
abjad> named_chromatic_pitch_1 == named_chromatic_pitch_2
False
abjad> named_chromatic_pitch_1 != named_chromatic_pitch_2
True
abjad> named_chromatic_pitch_1 > named_chromatic_pitch_2
False
abjad> named_chromatic_pitch_1 < named_chromatic_pitch_2
True
abjad> named_chromatic_pitch_1 >= named_chromatic_pitch_2
False
abjad> named_chromatic_pitch_1 <= named_chromatic_pitch_2
True
13.7. Converting one type of pitch to another¶
Convert any named chromatic pitch to a named diatonic pitch:
abjad> named_chromatic_pitch.named_diatonic_pitch
NamedDiatonicPitch("c''")
To a numbered chromatic pitch:
abjad> named_chromatic_pitch.numbered_chromatic_pitch
NumberedChromaticPitch(13)
Or to a numbered diatonic pitch:
abjad> named_chromatic_pitch.numbered_diatonic_pitch
NumberedDiatonicPitch(7)
13.8. Converting pitches to pitch-classes¶
Convert any named chromatic pitch to a named chromatic pitch-class:
abjad> named_chromatic_pitch.named_chromatic_pitch_class
NamedChromaticPitchClass('cs')
To a named diatonic pitch-class:
abjad> named_chromatic_pitch.named_diatonic_pitch_class
NamedDiatonicPitchClass('c')
To a numbered chromatic pitch-class:
abjad> named_chromatic_pitch.numbered_chromatic_pitch_class
NumberedChromaticPitchClass(1)
Or to a numbered diatonic pitch-class:
abjad> named_chromatic_pitch.numbered_diatonic_pitch_class
NumberedDiatonicPitchClass(0)
13.9. Copying pitches¶
Use copy.copy() to copy named chromatic pitches:
abjad> import copy
abjad> copy.copy(named_chromatic_pitch)
NamedChromaticPitch("cs''")
Or use copy.deepcopy() to do the same thing.
13.10. Accidental abbreviations¶
Abjad abbreviates accidentals according to the LilyPond english.ly module:
accidental name abbreviation quarter sharp ‘qs’ quarter flat ‘qf’ sharp ‘s’ flat ‘f’ three-quarters sharp ‘tqs’ three-quarters flat ‘tqf’ double sharp ‘ss’ double flat ‘ff’
13.11. Chromatic pitch numbers¶
Abjad numbers chromatic pitches by semitone with middle C set equal to 0:
The code to generate this table is as follows:
score, treble_staff, bass_staff = scoretools.make_empty_piano_score()
duration = Fraction(1, 32)
treble = measuretools.AnonymousMeasure([])
bass = measuretools.AnonymousMeasure([])
treble_staff.append(treble)
bass_staff.append(bass)
pitches = range(-12, 12 + 1)
configurationtools.set_default_accidental_spelling('sharps')
for i in pitches:
note = Note(i, duration)
rest = Rest(duration)
clef = pitchtools.suggest_clef_for_named_chromatic_pitches([note.pitch])
if clef == contexttools.ClefMark('treble'):
treble.append(note)
bass.append(rest)
else:
treble.append(rest)
bass.append(note)
diatonic_pitch_number = str(note.pitch.numbered_chromatic_pitch)
markuptools.Markup(diatonic_pitch_number, 'down')(bass[-1])
score.override.rest.transparent = True
score.override.stem.stencil = False
show(score, 'paris.ly')
13.12. Diatonic pitch numbers¶
Abjad numbers diatonic pitches by staff space with middle C set equal to 0:
The code to generate this table is as follows:
score, treble_staff, bass_staff = scoretools.make_empty_piano_score()
duration = Fraction(1, 32)
treble = measuretools.AnonymousMeasure([])
bass = measuretools.AnonymousMeasure([])
treble_staff.append(treble)
bass_staff.append(bass)
pitches = []
diatonic_pitches = [0, 2, 4, 5, 7, 9, 11]
pitches.extend([-24 + x for x in diatonic_pitches])
pitches.extend([-12 + x for x in diatonic_pitches])
pitches.extend([0 + x for x in diatonic_pitches])
pitches.extend([12 + x for x in diatonic_pitches])
pitches.append(24)
configurationtools.set_default_accidental_spelling('sharps')
for i in pitches:
note = Note(i, duration)
rest = Rest(duration)
clef = pitchtools.suggest_clef_for_named_chromatic_pitches([note.pitch])
if clef == contexttools.ClefMark('treble'):
treble.append(note)
bass.append(rest)
else:
treble.append(rest)
bass.append(note)
diatonic_pitch_number = abs(note.pitch.numbered_diatonic_pitch)
markuptools.Markup(diatonic_pitch_number, 'down')(bass[-1])
score.override.rest.transparent = True
score.override.stem.stencil = False
show(score, 'paris.ly')
13.13. Octave designation¶
Abjad designates octaves with both numbers and ticks:
Octave notation Tick notation C7 c’‘’‘ C6 c’‘’ C5 c’‘ C4 c’ C3 c C2 c, C1 c,,
13.14. Accidental spelling¶
Abjad chooses between enharmonic spellings at pitch-initialization according to the following table:
Chromatic pitch-class number Chromatic pitch-class name (default) 0 C 1 C# 2 D 3 Eb 4 E 5 F 6 F# 7 G 8 Gb 9 A 10 Bb 11 B
abjad> staff = Staff([Note(n, (1, 8)) for n in range(12)])
abjad> show(staff)
Use pitch tools to respell with sharps:
abjad> pitchtools.respell_named_chromatic_pitches_in_expr_with_sharps(staff)
abjad> show(staff)
Or flats:
abjad> pitchtools.respell_named_chromatic_pitches_in_expr_with_flats(staff)
abjad> show(staff)
