SuperCollider CLASSES

Logistic

Chaotic noise function
Inherits from: UGen : AbstractFunction : Object

Description

A noise generator based on the logistic map:

y = chaosParam * y * (1.0 - y)

Class Methods

*ar (chaosParam: 3, freq: 1000, init: 0.5, mul: 1, add: 0)

*kr (chaosParam: 3, freq: 1000, init: 0.5, mul: 1, add: 0)

Arguments:

chaosParam

a parameter of the chaotic function with useful values from 0.0 to 4.0. Chaos occurs from 3.57 up. Don't use values outside this range if you don't want the UGen to blow up.

freq

Frequency of calculation; if over the sampling rate, this is clamped to the sampling rate

init

Initial value of y in the equation above

mul

Output will be multiplied by this value.

add

This value will be added to the output.

Discussion:

y will stay in the range of 0.0 to 1.0 for normal values of the chaosParam. This leads to a DC offset, and may cause a pop when you stop the Synth. For output you might want to combine this UGen with a LeakDC or rescale around 0.0 via mul and add: see example below.

Inherited class methods

Instance Methods

Inherited instance methods

Examples

// default values
{ Logistic.ar }.play

// onset of chaos
{ Logistic.ar(Line.kr(3.55, 3.6, 5), 1000) }.play

// explore via Mouse
{ Logistic.ar(MouseX.kr(3, 3.99), MouseY.kr(10, 10000, 'exponential'), 0.25, 0.5) }.play