On Fri, Apr 9, 2010 at 11:43 AM, John Nagle <na...@animats.com> wrote: > Chris Rebert wrote: >> On Fri, Apr 9, 2010 at 8:04 AM, Peyman Askari <peter_peyman_...@yahoo.ca> >> wrote: >>> >>> Hello >>> >>> This is partly Python related, although it might end up being more math >>> related. >>> >>> I am using PyGTK (GUI builder for Python) and I need to find the >>> intersection point for two lines. It is easy to do, even if you only have >>> the four points describing line segments >>> (http://www.maths.abdn.ac.uk/~igc/tch/eg1006/notes/node23.html). However, it >>> requires that you solve for two equations. How can I do this in Python, >>> either solve equations, or calculating intersection points some other way? >> >> Just solve the equations ahead of time by using generic ones. <snip> >> x = (c - b) / (m-n) > > Actually, you don't want to do it that way, because it fails for vertical > lines, when m and n go to infinity.
As the programmer said upon seeing a stripe-less zebra: "Oh no, a special case!" Excellent catch my good sir; although I will point out that strictly speaking, you can't put vertical lines into slope-intercept form (but I should not have forgotten that precondition). Cheers, Chris -- Vertical line test, etc. http://blog.rebertia.com -- http://mail.python.org/mailman/listinfo/python-list