rsc3/doc-schelp/HelpSource/Classes/Pwrand.scrbl

51 lines
988 B
Text
Raw Permalink Normal View History

2022-08-24 13:53:18 +00:00
#lang scribble/manual
@(require (for-label racket))
@title{Pwrand}
embed values randomly chosen from a list@section{related}
Classes/Prand, Classes/Pxrand
@section{categories}
Streams-Patterns-Events>Patterns>List
@section{description}
Returns one item from the list at random for each repeat, the probability for each item is determined by a list of weights which should sum to 1.0.
@section{Examples}
@racketblock[
(
var a, b;
a = Pwrand.new([1, 2, 3], [1, 3, 5].normalizeSum, 6); // return 6 items
b = a.asStream;
7.do({ b.next.postln; });
)
//Prand used as a sequence of pitches:
(
SynthDef(\help_sinegrain,
{ arg out=0, freq=440, sustain=0.05;
var env;
env = EnvGen.kr(Env.perc(0.01, sustain, 0.2), doneAction: Done.freeSelf);
Out.ar(out, SinOsc.ar(freq, 0, env))
}).add;
)
(
a = Pwrand([60, 61, 63, 65, 72], [10, 2, 3, 1, 3].normalizeSum, inf).asStream;
Routine({
loop({
Synth(\help_sinegrain, [\freq, a.next.midicps]);
0.1.wait;
})
}).play;
)
::
]