surf(Z) //  It creates a three-dimensional shaded surface from the z components in matrix Z, using x = 1:n and y = 1:m, where [m,n] = size(Z). 
surf(X,Y,Z) // It creates a shaded surface using Z for the color information as well as surface height. X and Y are vectors or matrices describing the x and y components of a surface.
surf(X,Y,Z,C) // It creates a shaded surface, with color defined by C.
surf(...,'PropertyName',PropertyValue) // It specifies surface properties along with the data.
surfc(...) // It draws a contour plot beneath the surface.
h = surf(...) // It return a handle to a surface graphics object.
h = surfc(...) // It return a handle to a surface graphics object.

z=cos x cos y e (-√(x^2+y^2 ))/4
|x|≤5,|y|≤5
u=-5:.2:5;
[X, Y]=meshgrid(u, u);
Z=cos(X). *cos(Y).*...
    exp (-sqrt(X.^2+Y.^2)/4);
surf(X, Y, Z)