clc
clear all
close all
I = [0 6 -6 6];
figure
hold
grid
f = @(x, y) exp(x).*sin(y);
fsurf(f, I)
pause
P1 = @(x, y) y;
fsurf(P1, I)
pause
P2 = @(x, y) y + x.*y;
fsurf(P2, I)