88 lines
1.3 KiB
Text
88 lines
1.3 KiB
Text
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#lang scribble/manual
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@(require (for-label racket))
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@title{QuadN}
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General quadratic map chaotic generator@section{categories}
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UGens>Generators>Chaotic
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@section{related}
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Classes/QuadL, Classes/QuadC
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@section{description}
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A non-interpolating sound generator based on the difference equation:
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teletype::
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x(n+1) = a * x(n)^2 + b * x(n) + c
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::
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sclang code translation:
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@racketblock[
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(
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var a = 1, b = -1, c = -0.75, xi = 0, size = 64;
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plot(size.collect { xi = (a * (xi ** 2)) + (b * xi) + c; xi });
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)
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::
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]
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@section{classmethods}
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@section{method}
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ar
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@section{argument}
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freq
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Iteration frequency in Hertz
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@section{argument}
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a
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Equation variable
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@section{argument}
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b
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Equation variable
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@section{argument}
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c
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Equation variable
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@section{argument}
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xi
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Initial value of x
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@section{argument}
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mul
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@section{argument}
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add
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@section{examples}
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@racketblock[
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// default params
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{ QuadN.ar(SampleRate.ir/4) * 0.2 }.play(s);
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::
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]
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@racketblock[
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// logistic map
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// equation: x1 = -r*x0^2 + r*x0
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(
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{ var r;
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r = MouseX.kr(3.5441, 4); // stable range
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QuadN.ar(SampleRate.ir/4, r.neg, r, 0, 0.1) * 0.4;
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}.play(s);
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)
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::
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]
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@racketblock[
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// logistic map as frequency control
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(
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{ var r;
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r = MouseX.kr(3.5441, 4); // stable range
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SinOsc.ar(QuadN.ar(40, r.neg, r, 0, 0.1, 800, 900)) * 0.4;
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}.play(s);
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)
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::
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]
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