See http://en.wikipedia.org/wiki/Problem_of_Apollonius
Dave On Oct 2, 7:57 am, eSKay <[email protected]> wrote: > This problem was a sub-part of one of the Google Codejam problems this > year. > > We have three circles, with radii and centers and we need to find the > center and radius of the circle that has the minimum radius and > encloses all these three circles. > > The first step can be to subtract the radius of the smallest circle > from the radii of all the other circles. This will not alter the > center of the resultant circle, we will just have to add the radius of > the smallest circle back to our answer. > > Now from here, what would be the best algorithm to calculate the > required center and radius? > > the solution given there says: > "We can subtract from the radius of each of the three plants the > radius of the smallest plant, then compute an inversion about that > plant's center. Then we find appropriate tangents to the two inverted > plants, re-invert to find the corresponding circle, and add back the > radius of the smallest plant." > > What exactly is "an inversion about that plant's center"? > > We can also discuss a different algorithm here that does the job! --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/algogeeks -~----------~----~----~----~------~----~------~--~---
