SuperCollider CLASSES

Pgbrown

geometric brownian motion pattern
Inherits from: Pbrown : Pattern : AbstractFunction : Object

Description

Returns a stream that behaves like a geometric brownian motion.

Class Methods

*new (lo: 0, hi: 1, step: 0.125, length: inf)

From superclass: Pbrown

Arguments:

lo

lower boundary of values.

hi

upper boundary of values.

step

maximum multiplication factor per step (omega) - the distribution is xrand2.

length

number of values produced.

Inherited class methods

Instance Methods

Inherited instance methods

Undocumented instance methods

-calcNext (cur, step)

Examples

(
var a, b;
a = Pgbrown(0.0, 1.0, 0.2, inf);
b = a.asStream;
7.do({ b.next.postln; });
)


// sound example
(
SynthDef(\help_sinegrain,
    { arg out=0, freq=440, sustain=0.05;
        var env;
        env = EnvGen.kr(Env.perc(0.01, sustain, 0.2), doneAction:2);
        Out.ar(out, SinOsc.ar(freq, 0, env))
    }).add;
)

(
var a;
a = Pgbrown(1.0, 2.0, 0.1, inf).asStream;
Routine({
    loop({
    Synth(\help_sinegrain, [\freq, a.next * 600 + 300]);
    0.02.wait;
    })
}).play;
)

// compare with normal brownian motion:

(
var a;
a = Pbrown(1.0, 2.0, 0.1, inf).asStream;
Routine({
    loop({
        Synth(\help_sinegrain, [\freq, a.next * 600 + 300]);
        0.02.wait;
    })
}).play;
)