For the mathematicians among you, have a look at:
http://tinyurl.com/5667g7
=@@i
Raul Miller schreef:
> I am playing around with a problem, and I feel like I am missing
> a couple basic concepts, so I was wondering if anyone had
> any quick suggestions:
>
> If I have code which finds a shortest cycle which visits all points in a set:
>
> loopdist=: +/@:(+/&.:*:"1)@:(- 1&|.)"2
> sortloops=:{.@(/: loopdist)@({~ (!@<: A.&i. ])@#)"2
>
> And I use this to generate some random quadrilaterals
> (with coordinates of each chosen arbitrarily from some
> linearly distributed range):
>
> data=: sortloops (?.20 4 2$1000)+"1"_1(1000*4 5 #:i.20)
>
> What are the odds that any given quadrilateral is
> not concave?
>
> require'plot'
> plot j./"1 (,{.)"2 data
>
> Thanks,
>
>
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