86 lines
1.5 KiB
Text
86 lines
1.5 KiB
Text
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#lang scribble/manual
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@(require (for-label racket))
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@title{LorenzL}
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Lorenz chaotic generator@section{categories}
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UGens>Generators>Chaotic
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@section{description}
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A strange attractor discovered by Edward N. Lorenz while studying mathematical models of the atmosphere. The system is composed of three ordinary differential equations:
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teletype::
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x' = s * (y - x)
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y' = x * (r - z) - y
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z' = x * y - b * z
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::
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The time step amount
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@racketblock[h:: determines the rate at which the ODE is evaluated. Higher values will increase the rate, but cause more instability. A safe choice is the default amount of 0.05.
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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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s
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Equation variable
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@section{argument}
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r
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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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h
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Integration time step
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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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yi
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Initial value of y
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@section{argument}
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zi
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Initial value of z
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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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// vary frequency
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{ LorenzL.ar(MouseX.kr(20, SampleRate.ir)) * 0.3 }.play(s);
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::
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]
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@racketblock[
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// randomly modulate params
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(
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{ LorenzL.ar(
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SampleRate.ir,
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LFNoise0.kr(1, 2, 10),
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LFNoise0.kr(1, 20, 38),
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LFNoise0.kr(1, 1.5, 2)
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) * 0.2 }.play(s);
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)
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::
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]
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@racketblock[
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// as a frequency control
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{ SinOsc.ar(Lag.ar(LorenzL.ar(MouseX.kr(1, 200)),3e-3)*800+900)*0.4 }.play(s);
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::
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]
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