[PD] algorithms for drawing filter response curves

[Hans-Christoph Steiner]

I've started to write a GUI for generating biquad coefficients  
(something like Max/MSP's [filtergraph~]).  I've gotten the GUI  
interaction working well, now I'm looking for the algorithms for  
generating a plot of the frequency response of a given set of biquad  
coefficents?  It'll end up being Tcl, but I can easily read C, Csound,  
Java, Perl, Python, etc.

.hc

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