Cross products with anonymous functions

I please need help with my code. I want to end up with a matrix. I have an anonymous function which I would like to pass various values (in a vector form) and then I want the outputs in a matrix form.

n = 4;
A = @(th) [-R.*cos(th),-R.*sin(th), 0];
theta = 0:pi/2:2*pi;

Lets say I have values for theta of 0:pi/n:2*pi; When I evaluate the function I get this:

u = 1×9    
   -0.0500   -0.0250    0.0250    0.0500         0   -0.0433   -0.0433   -0.0000         0

I understand that the vector has the answer vectors next to each other, but where are the intermediate 0's? I would expect the answer to have atleast 12 values.

This is so that I could cross product it with other matrices later on.

Any help would be much appreciated!

Answer 1

[Anton Gribovskiy]

If you sure that your th will always be 1-by-n vector, you just need to put semicolons instead of comas for vertical cat:

A = @(th) [-R.*cos(th);-R.*sin(th); zeros(1, length(th))];

Or, if you want to make it working for vertical and horizontal vectors

A = @(th) [-R.*cos(th(:).');-R.*sin(th(:).'); zeros(1, length(th))];

[Jonathan Rabe]

Thank you so much! I have been struggling to get this to work for hours now.