# Matlab - Using findpeaks with fvtool

Is there any way I could utilise findpeaks in conjunction with fvtool? I would like to know where on the frequency axis the maximum and minimum of my frequency response happens.

fvtool is interactive so it doesn't let you recover an data in a script. Fortunately you can use the freqz function to get the same frequency response. Something like this might work:
[h,w] = freqz(b,a);  % h is frequency response, w normalized frequency