Clockwise angle between points, Intersection between segments

ClockwiseAngle_SegmentIntersection

def clockwide_angle_between(p1, p2):
    '''
    Compute clockwise angle between 2 [x,y] points
    :param p1:  First point
    :type p1:   np.array([x1,y1])
    :param p2:  Second point
    :type p2:   np.array([x2,y3])
    :return:    clockwise angle between pt1 and pt2
    :rtype:     float64
    '''
    ang1 = np.arctan2(*p1[::-1])
    ang2 = np.arctan2(*p2[::-1])
    return np.rad2deg((ang1 - ang2) % (2 * np.pi))

def ccw(A,B,C):
    return (C[1]-A[1]) * (B[0]-A[0]) > (B[1]-A[1]) * (C[0]-A[0])

# Return true if line segments AB and CD intersect
# NOTE this doesn't handle edge cases of segment colinear or within another segment
def intersect(A,B,C,D):
    '''
    Compute whether line segments AB intersects CB
    :param A,B,C,D: #These are [X,Y] pairs
    :type A,B,C,D:  # np.array([1,2])
    :return: True if the line segment intersects, else False
    :rtype: bool
    '''
    return ccw(A,C,D) != ccw(B,C,D) and ccw(A,B,C) != ccw(A,B,D)