def _from_two_points(self, p1, p2):
x1, y1 = p1
x2, y2 = p2
if x1 == x2 or y1 == y2:
pass# raise Exception("slope == 0 or slope == oo")
c_x = (x1 + x2) / 2
c_y = (y1 + y2) / 2
r = euclidean_distance(p1, p2)
return c_x, c_y, r
def __contains__(self, p): return euclidean_distance(self.center(), p) <= self.r
