rsc3/doc-schelp/HelpSource/Classes/Pseed.schelp

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class:: Pseed
summary:: set the random seed in subpattern
related:: Reference/randomSeed
categories:: Streams-Patterns-Events>Patterns>Language Control
description::
Set the random generator seed of the resulting stream.
ClassMethods::
method::new
argument::randSeed
integer number, pattern or stream that return an integer number.
note::
randSeed is always treated as a pattern/stream. If you provide a single, constant seed value, it will behave as an infinite-length stream. This will cause the subpattern to be embedded an infinite number of times. Compare:
code::
// Pwhite repeats its three values forever
Pseed(1000, Pwhite(1, 10, 3)).asStream.nextN(10);
// Pwhite runs once:
// the output stream consists of three values, then 'nil' ad infinitum
Pseed(Pn(1000, 1), Pwhite(1, 10, 3)).asStream.nextN(10);
::
::
argument::pattern
Examples::
code::
a = Pseed(1972, Prand([1,2,3], inf));
b = a.asStream;
10.do({ b.next.post });
c = a.asStream;
10.do({ c.next.post });
// using a seed pattern as input:
a = Pseed(Pseq([1812, 1912], inf), Prand([1,2,3], 5));
b = a.asStream;
2.do({ 5.do({ b.next.post });"".postln; });
c = a.asStream;
2.do({ 5.do({ c.next.post });"".postln; });
// outer thread is independant:
a = Pseed(Prand([1534, 1600, 1798, 1986, 2005], inf), Pshuf([1, Prand([7, 9], 2), 1, 2, 3], 1));
// returns random streams
b = a.asStream;
2.do({ 5.do({ b.next.post });"".postln; });
c = a.asStream;
2.do({ 5.do({ c.next.post });"".postln; });
::