Tonality

A library for handling tonal pitch classes, keys, accidentals and alterations.

Example

You can find the tonal pitch classes of the notes in a chord by specifying the chord as a collection of (scale degree, alteration) pairs.

```rust use tonality::{Alteration, Key, Tpc};

type Chord = Vec<(isize, Alteration)>;

// The seventh in a dominant seventh chord is altered one semitone flat relative // to the major scale let dom7: Chord = vec![(0, 0), (2, 0), (4, 0), (6, -1)]; let key = Key::Fs; let chordtones: Vec = dom7 .iter() .filtermap(|&(scaledeg, alter)| key.scaledegree(scale_deg).alter(alter)) .collect();

let expected = vec![Tpc::Fs, Tpc::As, Tpc::Cs, Tpc::E]; asserteq!(expected, chordtones); ```

Inspiration

Types and operations, in particular the Tpc type, are influenced by Musescore's internal library.

Related crates

pitch_calc lets you convert between a number of different pitch representations, including the frequency domain.

rust-music-theory supports procedurally utilizing music theory notions like Note, Chord, Scale, Interval and more.

This crate might support conversion to and from types in the above mentioned crates in the future.