dir2par.m

the file contain many matlab signal source code and many example .

function [C,B,A]=dir2par(b,a);
% DIRECT - form to PARALLEL - form conversion 
% ---------------------------------
% [C,B,A]=dir2par(b,a)
% C=Polynomial part when length(b)>=length(a)
% B=K by 3 matrix of real coefficients containing bk's
% A=K by 3 matrix of real coefficients containing ak's
% b=numerator polynomial coefficients of DIRECT form 
% a=denominator polynomial coefficients of DIRECT form 
% 
M=length(b);N=length(a);
[r1,p1,C]=residuez(b,a);
p=cplxpair(p1,10000000*eps);
I=cplxcomp(p1,p);
r=r1(I);
K=floor(N/2);B=zeros(K,2);A=zeros(K,3);
if K*2==N;% N even,order of A(z) odd,one factor is first order
    for i=1:2:N-2
        Brow=r(i:1:i+1,:);
        Arow=p(i:1:i+1,:);
        [Brow,Arow]=residuez(Brow,Arow,[ ]);
        B(fix((i+1)/2),:)=real(Brow');
        A(fix((i+1)/2),:)=real(Arow');
    end
    [Brow,Arow]=residuez(r(N-1),p(N-1),[ ]);
    B(K,:)=[real(Brow') 0];A(K,:)=[real(Arow') 0];
else
    for i=1:2:N-1
        Brow=r(i:1:i+1,:);
        Arow=p(i:1:i+1,:);
        [Brow,Arow]=residuez(Brow,Arow,[ ]);
        B(fix((i+1)/2),:)=real(Brow');
        A(fix((i+1)/2),:)=real(Arow');
    end
end