Python求两个圆的交点坐标或三个圆的交点坐标方法

# -*- coding: utf-8 -*-
import math
import numpy as np
def insec(p1,r1,p2,r2):
 x = p1[0]
 y = p1[1]
 R = r1
 a = p2[0]
 b = p2[1]
 S = r2
 d = math.sqrt((abs(a-x))**2 + (abs(b-y))**2)
 if d > (R+S) or d < (abs(R-S)):
  print ("Two circles have no intersection")
  return 
 elif d == 0 and R==S :
  print ("Two circles have same center!")
  return
 else:
  A = (R**2 - S**2 + d**2) / (2 * d)
  h = math.sqrt(R**2 - A**2)
  x2 = x + A * (a-x)/d
  y2 = y + A * (b-y)/d
  x3 = round(x2 - h * (b - y) / d,2)
  y3 = round(y2 + h * (a - x) / d,2)
  x4 = round(x2 + h * (b - y) / d,2)
  y4 = round(y2 - h * (a - x) / d,2)
  print (x3, y3)
  print (x4, y4)
  c1=np.array([x3, y3])
  c2=np.array([x4, y4])
  return c1,c2
 
P1=np.array([-5,0])
R1=10
P2=np.array([5,0])
R2=5
C=insec(P1,R1,P2,R2)
C1=C[0]
C2=C[1]