comparison toolboxes/MIRtoolbox1.3.2/AuditoryToolbox/SecondOrderFilter.m @ 0:e9a9cd732c1e tip

first hg version after svn

+% filter = SecondOrderFilter(f, q, fs)
+% Design a second order digital filter with a center frequency of
+% f, filter quality of q, and digital sampling rate of fs (Hz).
+
+% (c) 1998 Interval Research Corporation  
+
+function filts = SecondOrderFilter(f,q,fs)
+cft = f'/fs;
+rho = exp(- pi * cft ./ q');
+theta = 2 * pi * cft .* sqrt(1-1 ./(4*q'.^2));
+filts = [ ones(size(rho)) -2*rho.*cos(theta) rho.^2 ];