def twiceTriangleArea(p0, p1, p2):
    """Returns twice the signed area of the triangle specified by the
    2D numpy points (p0, p1, p2)."""
    p1 = p1 - p0
    p2 = p2 - p0
    return p1[0] * p2[1] - p2[0] * p1[1]
