How to convert normalized frequency to logarithmic frequency in magnitude frequency response

Hi,

How to convert normalized frequency to logarithmic frequency.

I have magnitude response of filter,

x axis in normalized freq. 0 to 1(Sampling frequency).

I want to get the x axis in logarithmic frequencies.

How to do this in matlab?

Please any solutions for this

[Mathieu NOE]

hello

you can easily create your x axis (frequency) vector by using logspace :

assuming you want N values :

% start_freq is the min normalized frequency
% stop_freq is the max normalized frequency
% Fs is the sampling frequency
freq = logspace(log10(start_freq*Fs/2),log10(stop_freq*Fs/2),N);

[632541]

Thank you..

I'm using freqz(b,a) for IIR filter