>> clear %drawing 3-d graphs and surfaces >> [X Y]=meshgrid(-4:0.5:4,-1:0.1:1); an attempt to 3-d >> mesh(sin(X).*cos(Y)) >>

020

4060

80100

0

10

20

30-1

-0.5

0

0.5

1

With this change >> mesh(sin(X+Y).*cos(X-Y)) >>

020

4060

80100

0

10

20

30-1

-0.5

0

0.5

1

>> x=-0.5:0.005:0.5; >> y=x; >> [X Y]=meshgrid(x,y); >> mesh(X.^2+Y.^2) >>

050

100150

200250

0

100

200

3000

0.1

0.2

0.3

0.4

0.5

>> mesh(X.^2-Y.^2) >>

050

100150

200250

0

100

200

300-0.4

-0.2

0

0.2

0.4

>> x=-3:0.25:3; >> y=-3:0.25:3; >> [X Y] =meshgrid(x,y); >> Z=X.*exp(-X.^2+-Y.^2); >> s1=surf(X,Y,Z); >>

-4-2

02

4

-4

-2

0

2

4-0.5

0

0.5