> # sfb cylinderical spherical coordinates
> restart;with(plots);
> # cylindrical coordinates (r, theta, z) [Polar with z]
> x=r*cos(theta);y=r*sin(theta);z=z;
> r^2=x^2+y^2;tan(theta)=y/x;
> coordplot3d(cylindrical);
> coordplot(polar);
> # Examples (1,1,1) rectangular is (sqrt(2),Pi/4,1) cylinderical
> # (3,Pi,2) cylinderical is (-3,0,2) rectangular
> # 
> f:=r*sin(2*theta);
> plot3d([r*cos(theta),r*sin(theta),f],r=0..2,theta=0..2*Pi,axes=boxed,style=wireframe,title="polar plot example");
> #
> #spherical coordinates
> r=rho*sin(phi);z=rho*cos(phi);x=rho*cos(theta)*sin(phi);y=rho*sin(theta)*sin(phi);
> rho^2=r^2+z^2;rho^2=x^2+y^2+z^2;cos(phi)=z/rho;
> #Examples (1,1,1) rectangular is(sqrt(3), Pi/4, arccos(1/sqrt(3)) in spherical
> #
> coordplot3d(spherical);
> sphereplot(2,theta=0..2*Pi,phi=0..Pi);
> a:=sphereplot(2,theta=0..2*Pi,phi=0..Pi/4,scaling=constrained,axes=boxed):a;

> b:=cylinderplot(z,theta=0..2*Pi,z=0..sqrt(2)):b;
> display(a,b);