Rotation about X axis
R = rotx(THETA) R = rotx(THETA, 'deg')
R = ROTX(THETA) is a rotation matrix representing a rotation of THETA radians about the x-axis.
R = ROTX(THETA)
R = ROTX(THETA, 'deg') as above but THETA is in degrees.
R = ROTX(THETA, 'deg')