Created
February 25, 2012 16:13
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Ruby implementation of swap algorithm from http://beust.com/weblog/2012/02/20/various-ways-to-get-randomness-wrong/
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| # puts (1..100).to_a.shuffle.inspect | |
| class Array | |
| def shuffle | |
| size.downto(1) { |n| swap(n - 1, rand(n)) } | |
| self | |
| end | |
| def swap(x, y) | |
| self[x], self[y] = self[y], self[x] | |
| end | |
| end |
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FYI, this doesn't create an even distribution. Check out the blog post to find out why.