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−% RZ2IIR Return a,b IIR filter coefficients for a real zero designed using the bilinear transform.
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−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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−%
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−% DESCRIPTION: RZ2IIR Return a,b IIR filter coefficients for a real zero
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−%              designed using the bilinear transform.
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−%
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−% CALL:        [a,b] = rz2iir(z, fs)
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−%
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−% REMARK:      This is just a helper function. This function should only be
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−%              called from class functions.
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−%
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−% INPUT:       z  - zero object
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−%              fs - the sample rate for the filter
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−%
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−% VERSION:     $Id: rz2iir.m,v 1.7 2011/02/18 16:48:54 ingo Exp $
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−%
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−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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−
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−function varargout = rz2iir(varargin)
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−
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−  z  = varargin{1};
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−  fs = varargin{2};
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−  
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−  f0 = z.f;
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−  w0 = f0*2*pi;
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−
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−  a(1) = (2*fs + w0) / w0;
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−  a(2) = (-2*fs + w0) / w0;
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−
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−  b(1) = 1;
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−  b(2) = 1;
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−
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−  varargout{1} = a;
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−  varargout{2} = b;
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−end
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−