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Subject: Re: Random sampling with constraints
Date: Sun, 15 Apr 2012 17:09:07 +0000 (UTC)
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"Siva " <sivaathome@gmail.com> wrote in message <jmde4t$hd4$1@newscl01ah.mathworks.com>...
> I have a random [ 1 x m] vector of unique integers P. I need to randomly generate a [ 1 x n] vector S that is a subset of P that satisfies the requirement that the difference between any two integers in S is greater then "d".
- - - - - - - - - -
  If you wish to strictly avoid all bias in your random selection of S, I think in a problem of this nature it might very well be necessary to compute a list of all possible solutions and then randomly select one of them from that list.  If P and S are large and d is small, doing so could lead to an immense list of possible solutions, so this would be a rather desperate undertaking.  It is important that you perform the initial sorting operation.  Having done that I can envision a recursion process that has depth n (the number of elements to be placed in S) in which all possible solutions are found without repetition.  Are you sufficiently determined in avoiding bias to undertake such a method, or would some simpler heuristic method be adequate?

Roger Stafford