Circle-circle intersection points

algorithm math geometry intersection
fmark picture fmark · Jul 28, 2010 · Viewed 88.1k times · Source

How do I calculate the intersection points of two circles. I would expect there to be either two, one or no intersection points in all cases.

I have the x and y coordinates of the centre-point, and the radius for each circle.

An answer in python would be preferred, but any working algorithm would be acceptable.

Answer

Jacob picture Jacob · Jul 28, 2010

Intersection of two circles

Written by Paul Bourke

The following note describes how to find the intersection point(s) between two circles on a plane, the following notation is used. The aim is to find the two points P3 = (x3, y3) if they exist.

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