Defines the shape of the returned array of quaternions. If None
(the default), returns a quaternion 4-vector.
random_state : integer or numpy.RandomState, optional
The generator used for random numbers. If an integer is given,
it fixes the seed. Defaults to the global numpy random number
generator.
Returns:
out : ndarray
Array of quaternion 4-vectors. Given a size of, for example,
(m,n), m*n samples are generated. Because each sample is
4-dimensional, the output shape is ``(m,n,4)`. If no shape is
specified, a single (4-D) sample is returned.