unit vector rotation matrix

Hello! I am new to matlab, and so I have to ask stupid questions.... I am looking for the correct syntax for setting up a geometric vector rotation matrix that I stupidly thought would look something like this: f(x)= [cosX sinx 0; -sinX cosX 0; 0 0 1], where this is the matrix for the Z - axis, and X is the angle. I guess I have to define variables first , but here I am clueless when it comes to matlab. Can someone help me out here ? I am having a hard time with this as I am used to all the C++ syntax I usually deal with. I appreciate any help on the matter :-)

[Andrei Bobrov]

http://en.wikipedia.org/wiki/Rotation_matrix

Answer 1

[UJJWAL]

Hi, No question is a stupid question. If you are looking to rotate an object then in that case you can do so more easily with the rotate function. Look for it in the MATLAB help. It is much more easier. In case you dont figure it out or you want something else then reply back. I will get back to you.

Happy to Help

UJJWAL

Answer 2

[Jan]

Using SIN and COS is equivalent to C++:

x = 0.1;         % Angle in radians
R = [cos(x), sin(x), 0; -sin(x), cos(x), 0; 0, 0, 1];
v = rand(3, 1);  % Test vector
vR = R * v;      % Matrix multiplication

An common method to solve such questions is asking Google for "Matlab rotation matrix".

[Eivind]

Thank you very much for your answer. I was going to "accept" both answers I got here but then realized I could only accept 1. Sorry for that.