samer@0: % adyniir - Apply dynamic IIR filter to input signal
samer@0: %
samer@0: % adyniir :: arrow({[[K,N+1]], [[K,M]]}, {[[K,M]]}, [[K,N]]).
samer@0: %
samer@0: % N is the order of the IIR filter
samer@0: % K is the number of independent channels to filter.
samer@0: % M is the number of consecutive samples in input signal
samer@0: 
samer@0: function o=adyniir
samer@0: 	o=loop1(2,1,@(s1,s2)deal( ifx(s2(2)==1,@next1,@nextm), zeros(s1(1),s1(2)-1)));
samer@0: end
samer@0: 
samer@0: 
samer@0: function [y,yp]=next1(a,x,yp)
samer@0: 	y=x-sum(a(:,2:end).*yp,2);
samer@0: 	yp=[y,yp(:,1:end-1)];
samer@0: end
samer@0: 
samer@0: function [y,yp]=nextm(a,x,yp)
samer@0: 	M=size(x,2);
samer@0: 	y=zeros(size(x));
samer@0: 	for i=1:M
samer@0: 		[y(:,i),yp]=next1(a,x(:,i),yp);
samer@0: 	end
samer@0: end