[X,Y,Z] = cylinder(r) function explanation

What does the [X,Y,Z]=cylinder(r) function do for a given variable r intuitively? The explanation on the function page isn't very clear, I'm not sure what they mean by a profile curve. And further, what would doing, say, mesh(X) produce?

Answer 1

[John D'Errico]

Why not try it?

r = linspace(1,5,25);
[X,Y,Z]=cylinder(r);
surf(X,Y,Z)

I won't show you the plot, because you need to try these things! Look at what came out. Think about what went in. If you never try things in MATLAB you will never learn anything.

Now try the same test, but with

r = ones(10,1);
...

Does this look like a more traditional cylinder?

Now, what would you expect to see for this case:

r = sqrt(linspace(0,10,100));
...

Is there a name for that general class of surface? What do all of these surfaces tell you about the behavior of the cylinder function? Now go back and re-read the help.

[Vivek Puduri]

this is great! I'm able to use this code to change the base and top radius, however how would I change the height of the cylinder past 1?

Answer 2

[Manuel Cornejo Muñoz]

But the example that provides Mathworks in Getting Started is not so obvious. Take a look at subplot z. You see:

t = 0:pi/10:2*pi;

[X,Y,Z] = cylinder(4*cos(t));

subplot(2,2,1); mesh(X); title('X');

subplot(2,2,2); mesh(Y); title('Y');

subplot(2,2,3); mesh(Z); title('Z');

subplot(2,2,4); mesh(X,Y,Z); title('X,Y,Z');