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#X text 61 93 Stuff to test it:;
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#X text 220 296 coefficient (real and imaginary part);
#X msg 62 181 set 0.6 0.8;
#X text 32 374 where y[n] is the output \, x[n] the input \, and a[n] the filter coefficient (all complex numbers). The filter is always stable., f 64;
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#X text 32 414 The transfer function is H(Z) = -a + Z^-1., f 64;
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#X text 8 623 see also:;
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#X text 309 555 real;
#X text 308 577 complex;
#X text 107 536 1-pole;
#X text 167 536 1-zero;
#X text 234 520 1-zero \, reversed, f 8;
#X text 16 560 summary of raw filters:, f 12;
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#X obj 201 622 vcf~;
#X text 282 622 - user-friendly filters;
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#X text 184 652 - not so friendly;
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#X msg 11 139 browse http://msp.ucsd.edu/techniques/latest/book-html/node127.html;
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#X text 329 652 updated for Pd version 0.38;
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#X text 105 11 - complex one-zero "reverse" filter;
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#X text 117 81 signal -;
#X text 180 81 signal to filter (real part)., f 49;
#X text 117 149 signal -;
#X text 180 149 signal to filter (imaginary part)., f 49;
#X text 117 182 signal -;
#X text 117 212 signal -;
#X text 180 212 filter coefficient (imaginary part)., f 49;
#X text 180 182 filter coefficient (real part)., f 49;
#X text 124 119 clear -;
#X text 180 99 set internal state (real and imaginary part)., f 49;
#X text 180 119 clear internal state to zero (same as "set 0 0").;
#X text 71 353 1) list - real and imaginary part of coefficient (default 0 0)., f 64;
#X text 117 301 signal - filtered signal \, imaginary part.;
#X text 117 275 signal - filtered signal \, real part.;
#X text 33 99 set <float \, float> -;
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#X text 460 11 <= click;
#X text 96 11 - complex one-zero "reverse" filter;
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#X text 27 44 [czero_rev~] filters a complex audio signal (first two inlets) via a raw one-zero (non-reccursive) filter \, whose coefficients are controlled by creation arguments or by another complex audio signal (remaining two inlets). The impulse response is that of "rzero" reversed in time., f 64;
#X obj 51 282 czero_rev~ 0.9 0.4;
#X text 191 282 <-- creation arguments initialize filter;
#X text 212 257 <-- filter coefficient (imaginary part);
#X text 172 234 <-- filter coefficient (real part);
#X text 131 209 <-- signal to filter (imaginary part);
#X text 95 154 <-- clear internal state (last samples) to zero;
#X text 99 127 <-- signal to filter (real part);
#X text 15 448 Pd also provides a suite of user-friendly filters. This and other raw filters are provided for situations which the user-friendly ones can't handle. See Chapter 8 of http://msp.ucsd.edu/techniques.htm for an introduction to the necessary theory (click) -->, f 69;
#X text 41 324 The action of [czero_rev~] is:;
#X text 94 347 y[n] = -a[n] * x[n] + x[n-1];
#X text 148 182 <-- set internal state (real & imaginary parts);
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