remez - Remez's algorithm

Calling Sequence

[an]=remez(nc,fg,ds,wt)

Parameters

• nc : integer, number of cosine functions
• fg,ds,wt : real vectors
• fg : grid of frequency points in [0,.5)
• ds : desired magnitude on grid fg
• wt : weighting function on error on grid fg

Description

minimax approximation of a frequency domain magnitude response. The approximation takes the form

 h = sum[a(n)*cos(wn)]
   

for n=0,1,...,nc. An FIR, linear-phase filter can be obtained from the the output of remez by using the following commands:

                 hn(1nc-1)=an(nc-12)/2;
                 hn(nc)=an(1);
                 hn(nc+12*nc-1)=an(2nc)/2;
   

where an = cosine filter coefficients

See Also

remezb