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An Elegant Pairing Function [pdf] (szudzik.com)
3 points by codeismightier 4199 days ago
1 comments
sorokod 4199 days ago
|R x R| = |R| so the existence of such functions is guaranteed but it is nice to see that some are just a method call away. Does anyone know what pairing function on non negative integers is the most efficient in the number of bits it requires ?
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Someone 4199 days ago
This PDF only handles mapping N x N to N and vice versa, though.

For R x R, I would mix the bits of the two numbers

  [a0 a1 a2 a3...]
  [b0 b1 b2 b3...]
to

  [a0 b0 a1 b1 a2 b2 a3 b3...]
I am not sure that is a computable function for infinite-length bit sequences, though. Maybe none of those mapping functions are?
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sorokod 4199 days ago
Ah yes, I was thinking |N x N| = |N|. So is there a pairing function f: NxN -> N which can be used as compression?
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