neoscore.western.pitch

class neoscore.western.pitch.Pitch[source]

Bases: object

A written pitch with a letter, octave, and accidental.

This class does not define an actual concert pitch, MIDI code, pitch class, etc. associated with it. Users building notation systems on it can decide whether this represents a concert pitch or a written one. Neoscore’s western module treats it mostly as a written pitch, unconditionally writing provided accidentals regardless of context and key signatures.

The class supports a helpful shorthand for standard western 12-EDO pitches inspired by Lilypond’s pitch notation; see Pitch.from_str.

Extended accidentals are fully supported by passing arbitrary SMuFL glyph names to the accidental attribute.

letter: str

The a-g letter name of the pitch.

accidental: Optional[AccidentalType | str]

An accidental associated with the pitch.

For conventional accidentals, this can be an AccidentalType. Alternatively, this can be an arbitrary SMuFL glyph name string.

octave: int

The octave number, where 4 is the octave starting with middle-C.

classmethod from_str(shorthand: str) → Pitch[source]

Create a conventional Western Pitch from a string shorthand.

The pitch shorthand is inspired by Lilypond’s. It consists of three parts: a pitch letter, an optional accidental, and an optional octave mark.

  • Pitch letters are the standard c through b letters.

  • The accidental may be f or b for flat, s or # for sharp, n for natural, ss or x for double-sharp, and ff or bb for double-flat.

  • The octave indication is given by a series of apostrophes (') or commas (,), where each apostrophe increases the pitch by an octave, and each comma decreases it. All octave transformations are relative to the octave starting at middle-C. The absence of an octave indicator means a pitch is within the octave starting at middle-C. (Note that this differs from Lilypond’s notation, which starts at the octave below middle-C.)

Some examples:

  • Middle-C: c

  • The B directly below that: b,

  • The C one octave below middle-C: c,

  • The E-flat above middle-C: ef or eb

  • The F-sharp above middle-C: fs or f#

  • The G-double-sharp above middle-C: fx or fss

  • The A-double-flat above the treble staff: aff' or abb'

classmethod from_def(pitch_def: PitchDef) → Pitch[source]
__init__(letter: str, accidental: Optional[AccidentalType | str], octave: int) → None
property diatonic_degree_in_c: int

The diatonic degree of the pitch as if it were in C.

>>> Pitch.from_str("c").diatonic_degree_in_c
1
>>> Pitch.from_str("c'").diatonic_degree_in_c
1
>>> Pitch.from_str("d'''").diatonic_degree_in_c
2
>>> Pitch.from_str("bf,").diatonic_degree_in_c
7
property staff_pos_from_middle_c: float

The pitch’s staff position relative to middle C.

Values are in numeric pseudo-staff-units where positive values mean positions below middle C, and negative values mean positions above it.

>>> Pitch.from_str("c").staff_pos_from_middle_c
0
>>> Pitch.from_str("cs").staff_pos_from_middle_c
0
>>> Pitch.from_str("d").staff_pos_from_middle_c
-0.5
>>> Pitch.from_str("d'").staff_pos_from_middle_c
-4
>>> Pitch.from_str("cn,,").staff_pos_from_middle_c
7
neoscore.western.pitch.PitchDef

Shorthand for a Pitch

May be either a Pitch, a pitch string shorthand (see Pitch.from_str), or a Pitch init arg tuple.

alias of Union[Pitch, str, tuple]