invfreqz Fit filter B(z)/A(z)to the complex frequency response H at frequency points F. A and B are real polynomial coefficients of order nA and nB. [B,A,C] = invfreqz(H,F,nB,nA,W,iter,tol,trace) [B,A,C] = invfreqz(H,F,nB,nA,W) [B,A,C] = invfreqz(H,F,nB,nA) H: desired complex frequency response. F: frequency (must be same length as H). nB: order of the numerator polynomial B. nA: order of the denominator polynomial A. W: vector of weights (must be same length as F). This is an Octave function. Fit filter B(z)/A(z)to the complex frequency response H at frequency points F. A and B are real polynomial coefficients of order nA and nB. Optionally, the fit-errors can be weighted vs frequency according to the weights W. Note: all the guts are in invfreq.m