def quaternion_imag ( quaternion ) : return numpy . array ( quaternion [ 1 : 4 ] , dtype = numpy . float64 , copy = True )
python imaginary part of complex number array
Return imaginary part of quaternion .
def quaternion_imag(quaternion):
    """Return imaginary part of quaternion.

    >>> quaternion_imag([3, 0, 1, 2])
    array([ 0.,  1.,  2.])

    """
    return numpy.array(quaternion[1:4], dtype=numpy.float64, copy=True)