docs: def get_point(theta_ik, theta_jk, Pi, Pj):
      """ Calculate coordinates of point Pk given two points Pi, Pj and inner angles.  :param theta_ik: Inner angle at Pi to Pk.
      :param theta_jk: Inner angle at Pj to Pk.
      :param Pi: Coordinates of point Pi.
      :param Pj: Coordinates of point Pj.
  
      :return: Coordinate of point Pk.
      """
      A = np.array([[sin(theta_ik), -cos(theta_ik)],
                    [sin(theta_jk), -cos(theta_jk)]])
      B = np.array([[sin(theta_ik), -cos(theta_ik), 0, 0],
                    [0, 0, sin(theta_jk), -cos(theta_jk)]])
      p = np.r_[Pi, Pj]
      Pk = np.linalg.solve(A, np.dot(B, p))
      return Pk