Help using Circles intersection

[penbeuz]

Hello, trying to use your library for mechanical calculation but not being a mathematicians I don't understand how to use the result of intersection of circles.

C1 = Circle(Point(0,0),5)
C2 = Circle(Point(8,0),5)
l = Line(Point(4,0), Point(4,1))
A = C1.intersect(C2)
B = C1.intersect(l)
C = C2.intersect(l)

This is the result of circles intersection

A
[Point((5.014458341998072+0.010710064639031416j), (0.13325313668481312-0.40303121043641016j)),
 Point((19.770205823088897-0.16649271512070937j), (0.17208666613531612+19.12754381209912j)),
 Point((19.770205823088894-0.16649271512071231j), (-0.17208666613532006-19.12754381209912j)),
 Point((5.014458341998073+0.010710064639031925j), (-0.1332531366848131+0.4030312104364105j))]

The expected points are on both intersections of line with circles

Point(4.0,3.0) in B
True
Point(4.0,-3.0) in B
True
Point(4.0,3.0) in C
True
Point(4.0,-3.0) in C
True

But not on intersection of circles

Point(4.0,3.0) in A
False
Point(4.0,-3.0) in A
False

What am I missing ?
Thanks an best regards

[jan-mue]

There seems to be a mathematical error in the formula that we use to calculate the intersections of two conics. The two circles should obviously have the two expected points of intersection and two additional complex points of intersection. I will look into this issue.