Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ ¹ ² ³ °
 

You are not logged in. #1 20051114 04:53:49
Here's one for you...How can you find the amount of common surface area between 2 triangles, knowing the coordinates of all the 6 tips (and thus being able to calculate areas), without actually calculating intersections between edges, just by adding and substracting the different areas? An intelligent man usually knows how to reach his goals. A wise man also knows what goals to reach... #2 20051114 06:29:49
Re: Here's one for you...It looks tricky. You could sketch the two triangles to see which of the lines overlap, work out the points of the shape formed and use the semiperimeter rule to work out the area of that shape (splitting the shape up into triangles if it has 4, 5 or 6 sides), but you said you didn't want it to be done that way. Why did the vector cross the road? It wanted to be normal. #3 20051114 18:58:56
Re: Here's one for you...The only restriction is that I may not calculate any edge intersections. Other than that, anything goes. I have tried splitting the triangles into more triangles and using their areas in additions and calculations, nothing I tried worked... An intelligent man usually knows how to reach his goals. A wise man also knows what goals to reach... #4 20051114 19:31:58
Re: Here's one for you...What a cool project! "The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  Leon M. Lederman #5 20051115 05:11:36
Re: Here's one for you...Why can't you calculate the intersections? Is it too computationally intensive? El que pega primero pega dos veces. #6 20051115 06:09:38
Re: Here's one for you...i now realise my approach was wrong. The reason i don't wan't to use edge intersection is that this would lead to a huge increase in complexity when coding. This little problem is only part of a much larger one that involves many other little problems all of which, once solved, will need to be computed as efficiently as possible by a computer... This means that the simplest/fastest formula will need to be used. Of course, a formula is always better than an algo. An intelligent man usually knows how to reach his goals. A wise man also knows what goals to reach... #7 20051115 07:19:10
Re: Here's one for you...Maybe if you explained what your goals are ... give us a wider picture of what you are after. "The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  Leon M. Lederman 