clear

%[x,y] = meshgrid(-100:1:100);
[x,y] = meshgrid(-10:0.05:10);
z=(round(x+0.5)).^2+(round(y+0.5)).^2;
mesh(x,y,z);
title('Step Function','FontSize',16);
%axis([-100,100,-100,100,0,10000]);