How to divide the discrete time signal into segment according to its period?

here is the sampled signal v(n)=a*sin(2*pi*f1/fs)*(1+M*0.5*sign(sin(2*pi*n*fm/fs))) n=0,1,...N-1 Where, fs is the sampling frequency.

how to do segmentation using FIX function,for the N section of sample data

pl rpl soon...my objective is to use p=FIX(f1/fs) for N samples .After carrying out the segmentation,q=FIX(N/N') section ofdata will be available.. therby obtaining v(0)...................v(p-1) v(1)....................v(2p-1)

upto v(N-p)..............v(N-1)

pl write the necessary code in matlab