For finding all possible combinations of pairs amongst a group
To use please edit the pair_organiser.rb file on the root (to include your set of individuals for pairing) and run like so:
$ ruby pair_organiser.rb
[[["Pablo", "Dan"], ["Andrew", "Tom"], ["Rob", "Jay"], ["Norm", "Yev"]],
[["Pablo", "Andrew"], ["Dan", "Tom"], ["Rob", "Norm"], ["Jay", "Yev"]],
[["Pablo", "Tom"], ["Dan", "Andrew"], ["Rob", "Yev"], ["Jay", "Norm"]],
[["Pablo", "Rob"], ["Dan", "Jay"], ["Andrew", "Norm"], ["Tom", "Yev"]],
[["Pablo", "Jay"], ["Dan", "Rob"], ["Andrew", "Yev"], ["Tom", "Norm"]],
[["Pablo", "Norm"], ["Dan", "Yev"], ["Andrew", "Rob"], ["Tom", "Jay"]],
[["Pablo", "Yev"], ["Dan", "Norm"], ["Andrew", "Jay"], ["Tom", "Rob"]]]
NOTE: This algorithm employed uses a pseudo-random search and is not guaranteed to terminate. I have successfully run the algorithm for up to 34 individuals, but it took six non-terminating runs before the correct solution could be generated. If the algorithm gets stuck on a large pairing set do ctrl-C and restart a few times to see if another pseudo-random path will generate a solution.
Question on math StackExchange related to the above issue:
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