I don't know if this is what you're asking, but iirc it's really just a matter of substituting exp(j*2*pi*fc/Fs) for z in the transfer function. I can send a Pd patch illustrating it later, if you like.
.mmb
On Sunday, February 6, 2011, Hans-Christoph Steiner hans@at.or.at wrote:
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
All mankind is of one author, and is one volume; when one man dies, one chapter is not torn out of the book, but translated into a better language; and every chapter must be so translated.... -John Donne
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