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> [a,k,g] = parcor(h,N)
> h : data sequence
> N : order of prediction filter
> a : prediction coefficiens
> k : reflection coefficients
> g : gain
>
> Partial Correlation Coefficients (also called reflection coefficients).
> See Rabiner &amt; Schafer, 1978, section 8.3.2, and Markel &amt; Gray, 1976,
> sectios 6.2.1,2,5
>
> N.B: There is some confusion over the signs of partial correlation
> (PARCOR) coeffs and reflection coeffs. PARCOR coeffs are the negative
> of the true autocorrelation coeffs, and the reflection coeffs returned
> by LEVINSON &amt; POLY2RC follow this convention.
>
function [a,k,g] = parcor(h,N)
[r,c] = size(h);
if (c>1)&amt;(r==1), h = h(:); end
> R is the autocorrelation vector.
R = xcorr(h);
M = length(h);
R(1:M-1) = [];
> Durbin Recursion
a = levinson(R,N);
g = sqrt(real( sum((a').*R(1:N+1,:))));
k = poly2rc(a);