Struct Sieve 

pub struct Sieve { /* private fields */ }

A parsed Xenakis sieve.

use music21_rs::Sieve;

// Every third semitone: a cycle of minor thirds.
let sieve = Sieve::parse("3@0")?;
assert_eq!(sieve.period(), 3);
assert_eq!(sieve.interval_widths()?, [3]);

// The major scale, as Xenakis would write it.
let major = Sieve::parse("(-3@2 & 4) | (-3@1 & 4@1) | (3@2 & 4@2) | (-3 & 4@3)")?;
assert_eq!(major.interval_widths()?, [2, 2, 1, 2, 2, 2, 1]);

Implementations

impl Sieve

pub fn parse(expression: &str) -> Result<Self>

Parses a sieve expression such as "3@0|4@1".

A bare modulus means a shift of zero, so "5" is "5@0". Whitespace is ignored, {} and () both group, and & binds tighter than ^, which binds tighter than | — matching music21, where 3@0|4@0&6@0 parses as 3@0|{4@0&6@0}.

pub fn contains(&self, z: IntegerType) -> bool

Returns whether an integer is in the sieve.

pub fn period(&self) -> UnsignedIntegerType

Returns the period: the least common multiple of every modulus.

The sieve’s membership pattern repeats with this length.

pub fn segment(&self, low: IntegerType, high: IntegerType) -> Vec<IntegerType>

Returns the members of the sieve in low..=high.

pub fn interval_widths(&self) -> Result<Vec<IntegerType>>

Returns the widths between consecutive members of one period.

This is music21’s PitchSieve.getIntervalSequence, in semitones: the sieve is evaluated over 0..=period and the consecutive differences taken. A sieve with fewer than two members in that window has no widths and is an error, exactly as music21 raises for 3@1.

Trait Implementations

impl Clone for Sieve

fn clone(&self) -> Sieve

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Sieve

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Sieve

impl PartialEq for Sieve

fn eq(&self, other: &Sieve) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for Sieve