From: ThoML <micathom@...>
Date: 2008-02-18T01:54:55+09:00
Subject: Re: The Smallest Circle (#157)

And again I reply to my own post. The test code requires a distance()
method:

def distance(p1, p2)
    Math.sqrt((p1.x - p2.x) ** 2 + (p1.y - p2.y) ** 2)
end

In case somebody cares.