48 lines
563 B
Plaintext
Executable File
48 lines
563 B
Plaintext
Executable File
function eval_lfo2()
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L = 80000;
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fs = 48000;
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fstart = 10;
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fend = 1000;
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df = (fend-fstart)/L;
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ip = 0.0 % phase of the first output sample in radians
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% Init
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% Loop
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f = fstart;
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fchg = 0;
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ylast = 0;
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a = 0.5;
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b = 2.0 * sin(f*pi / fs);
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y0 = a*cos(2*pi*ip);
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y1 = a*sin(2*pi*ip);
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for n=1:L,
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y0 = y0 - b*y1;
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y1 = y1 + b*y0;
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fchg = (mod(n, 1000) == 0);
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if fchg
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b = 2.0 * sin(f*pi / fs);
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end
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ylast = y1;
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lfo(n) = y0;
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f = f + df;
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close all
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end;
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figure;
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plot(1:L, lfo); grid;
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wavwrite(0.5*lfo, fs, 'lfo.wav');
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