title: Matrix and vector multiplication in libdx
body: <p>I am trying to rotate a vector with a rotation matrix using LibGdx vector and matrix classes. However when I tried to multiply the vector by the matrix  it say that The method mul(float) in the type Vector3 is not applicable for the arguments (Matrix3). I know his supposed to work barbecue I check LibGdx documentation:
        Vector3 mul(Matrix3 matrix)
        Left-multiplies the vector by the given matrix. 
  So, it should work but I get the error mention above. At first I thought it was matrix dimension error but that should not be case the matrix is a 3 by 3 and the vector should be a 3 by 1. I think that I have more of syntax problem as I have not found any examples doing vector and matrix multiplication. Any help pointing in the right direction or a better way to rotate the vector would be really appreciated. Anyhow, Here is my code:</p>
  
  <pre><code>private Vector3 unrotatedPositon;
  private Vector3 rotatedPosition;
  private Matrix3 rotationMatrix;
  unrotatedPositon = new Vector3(asteroid1.getX(), asteroid1.getY() , 0);
  rotationMatrix = new Matrix3();
  rotationMatrix.setToRotation(45);
  rotatedPosition = unrotatedPositon.mul(rotationMatrix);
  </code></pre>