for ii in range(1,Z.shape[0]-1,2): for jj in range(1,Z.shape[1]-1,2): Z_diff1[ii,jj] = Z[ii-1, jj] - Z[ii+1,jj] # calculate centered finite difference using array slicing Z_diff2 = Z[:-2:2,::2] - Z[2::2,::2] # calculate centered finite difference using n...