Math

Magnitude, dropping the sign.

Linear amplitude to decibels, the inverse of db: 1.amp is 0. The amplitude must be above zero.

Beats per minute to bars per second. The beat is the quarter note; how many of them make a bar is the project's time signature, so 120.bpm is 0.5 in 4/4 — the default tempo — and 0.667 in 3/4, where the bar is shorter.

Smallest whole number at or above x.

Detune a frequency by cents, 1/100 of a semitone: 440.cents(-14) flattens A4 slightly.

Constrain a number to lo..=hi.

Decibels to a linear amplitude: 0.db is 1, -6.db is about 0.5. Use it to write gains the way you hear them.

Largest whole number at or below x.

Frequency in hertz to MIDI note number, the inverse of m2h: 440.h2m is 69. The result may be fractional.

Base-2 logarithm. x must be above zero.

MIDI note number to frequency in hertz: 69.m2h is 440. Equal temperament, A4 = 440 Hz.

Map 0..1 onto lo..hi. Values outside 0..1 extrapolate; clamp first if you do not want that.

Transpose a MIDI note by whole octaves: 60.oct(-1) is 48.

x raised to a power: 2.pow(10) is 1024. Good for exponential curve shaping.

Nearest whole number, halves away from zero.

Snap a MIDI note to the nearest tone of a scale, given as semitone offsets within an octave: 61.scale([0, 2, 4, 5, 7, 9, 11]) is 60. Ties snap down.

Transpose a MIDI note by semitones: 60.semi(7) is 67.

Square root. x must not be negative.

Fold a number back into lo..hi, wrapping around rather than clamping. Useful for modular pitch.