--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/m-toolbox/classes/@pz/rp2iir.m	Wed Nov 23 19:22:13 2011 +0100
@@ -0,0 +1,34 @@
+% RP2IIR Return a,b coefficients for a real pole designed using the bilinear transform.
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%
+% DESCRIPTION: RP2IIR Return a,b coefficients for a real pole designed using
+%              the bilinear transform.
+%
+% CALL:        filt = rpole(p, fs)
+%
+% REMARK:      This is just a helper function. This function should only be
+%              called from class functions.
+%
+% INPUT:       p  - pole object
+%              fs - the sample rate for the filter
+%
+% VERSION:     $Id: rp2iir.m,v 1.7 2011/02/18 16:48:54 ingo Exp $
+%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+function varargout = rp2iir(varargin)
+
+  p  = varargin{1};
+  fs = varargin{2};
+
+  f0 = p.f;
+  w0 = f0*2*pi;
+  a(1) = w0 / (2*fs + w0);
+  a(2) = a(1);
+  b(1) = 1;
+  b(2) = (w0-2*fs) / (w0+2*fs);
+
+  varargout{1} = a;
+  varargout{2} = b;
+end
+