THX for help and all answers. Code: for i in range(len(myinput)-m+1): cin=tempmatr[:] ctmp=tempmatr[i] xtmp=((numpy.abs(cin-ctmp))<=r)*1 x2tmp=numpy.sum(numpy.transpose(xtmp), axis=0) mcount=numpy.sum((x2tmp==m)*1) allcount=allcount+mcount works just fine. Now it's time to optimize my lib a little :D Regards