use sva_formula::note::frequency;
#[test]
fn the_tuning_anchor_and_its_equal_tempered_neighbours() {
assert_eq!(frequency(69), 440.0);
assert_eq!(frequency(81), 880.0, "an octave is a doubling");
assert!((frequency(60) - 261.6255653005986).abs() < 1e-9);
assert!((frequency(70) / 440.0 - 2f64.powf(1.0 / 12.0)).abs() < 1e-12);
}