how to calculate group delay in matlab?

[mega]

Hi,
I need to know the group delay of a analog filter.
The "grpdelay" seems for figital filter.
If I use this function, how to translate the samples to time of Y axis?

3Q

 

[amir_rastegar2003]

use this funtion im MATLAB:

grpdelay


thanks. (if this post is useful for you plz press "helped me" buttom).