Plotting a sphere or portions thereof
A sphere of radius 1:
> plot3d(1,theta=0..2*Pi,phi=0..Pi,coords=spherical,scaling=constrained,axes=frame);
>
A theta-restricted section of the sphere:
> plot3d(1,theta=Pi..2*Pi,phi=0..Pi,coords=spherical,scaling=constrained,axes=frame);
>
A phi-restricted section of the sphere:
> plot3d(1,theta=0..2*Pi,phi=Pi/4..Pi,coords=spherical,scaling=constrained,axes=frame);
>
A section of the sphere restricted by both theta and phi:
> plot3d(1,theta=Pi..2*Pi,phi=Pi/4..3*Pi/4,coords=spherical,scaling=constrained,axes=frame);
>