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I learned in college Geometry class that you can transform a square to an equilateral triangle in 11 cuts or so So I wrote a matlab program to draw the shapes,
by chubot 2y ago
I learned in college
Geometry class that you can transform a square to an equilateral triangle in 11 cuts or so
So I wrote a matlab program to draw the shapes, and cut them
out, and it works
It’s mathematically exact, not just approximate
Still surprises me after 20 years, so I want to find this old program again lol
- chubot 2y agoThis got a downvote and I wonder if it’s from a person who doesn’t think it’s true
- mike-the-mikado 2y agoOr perhaps from someone who doesn't think it's useless
- Someone 2y agoIt more likely s from a person whose fingers are much larger than the distance between the up/downvote triangles on their device (that’s about everybody)
- danparsonson 2y agoIndeed, although note that if you do fat-finger the up or down vote button, you can undo that by poking the 'unvote' or 'undown' link that appears on the same line.
- IAmGraydon 2y agoSome men just want to watch the world burn.
- quuxplusone 2y agoThe dissection of a square into an equilateral triangle (or vice versa) is sometimes known as the haberdasher's problem, and can be done in three straight-line cuts. https://mathworld.wolfram.com/HaberdashersProblem.html https://mathworld.wolfram.com/HaberdashersProblem.html
- chubot 2y agoHm interesting, I thought it was 11 pieces, not 11 cuts, but that one looks like 4 pieces, which is surprising Now I am more curious to find this program Either I didn't do it optimally, or there is some variation like a triangle/rectangle/square I think there are some problems that have 3 shapes, or it could be triangle/pentagon or something
- quuxplusone 2y agoTIL that Gavin Theobald has produced several dissections from a triangle to a square on the surface of a sphere. Which would make pretty cool 3D-printed desk gizmos: make a ball with a triangular sector removed from one pole, a square sector removed from the other pole, and a set of wedge-shaped pieces that can be used to fill up either hole. http://www.gavin-theobald.uk/HTML/Spherical/T90-S112.5.pdf http://www.gavin-theobald.uk/HTML/Spherical/T90-S112.5.pdf http://www.gavin-theobald.uk/HTML/Spherical/T100-S120.pdf http://www.gavin-theobald.uk/HTML/Spherical/T100-S120.pdf http://www.gavin-theobald.uk/HTML/Spherical/T120-S135.pdf http://www.gavin-theobald.uk/HTML/Spherical/T120-S135.pdf http://www.gavin-theobald.uk/HTML/Spherical.html http://www.gavin-theobald.uk/HTML/Spherical.html