Neeed help on low pass filter designing ?

I want to design a low pass filter which i can specify the parameter in this way

[h]=LowpassFilter(Fs,fs,fp,M)

Fs- sampling frequency fs- stop band frequency fp- pass band frequency M- window length

This is how i have design it but it doesn't work for me.

function h=LowpassFilter(Fs,fs,fp,M)

h=fdesign.lowpass('N,Fp,Fst',M,fp,fs,Fs );

please help me

Answer 1

[Wayne King]

What problem are you having. What error message are you getting?

   Fs = 1000;
   fp = 100;
   fst = 150;
   M = 30;
   h = fdesign.lowpass('N,Fp,Fst',M,fp,fst,Fs);