flux-algebra 0.1.0

Algebraic structures for music theory: HarmonicRing, PLR group, Tropical semiring, TuningField
Documentation 
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//! Tuning field: algebraic extensions for tuning systems.

/// A tuning field representing rational intervals.
#[derive(Debug, Clone)]
pub struct TuningField {
    pub base_frequency: f64,
    pub intervals: Vec<f64>,
}

impl TuningField {
    pub fn equal_temperament(n: usize) -> Self {
        Self {
            base_frequency: 440.0,
            intervals: (0..n).map(|i| 2.0_f64.powi(i as i32) / n as f64).collect(),
        }
    }
    pub fn frequency(&self, degree: usize) -> f64 {
        self.base_frequency
            * self
                .intervals
                .get(degree % self.intervals.len())
                .unwrap_or(&1.0)
    }
    pub fn cents(&self, ratio: f64) -> f64 {
        1200.0 * ratio.log2()
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    #[test]
    fn test_et() {
        let et = TuningField::equal_temperament(12);
        assert_eq!(et.intervals.len(), 12);
    }
}