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Date: Fri, 11 Jan 2013 14:36:57 +0000
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Subject: Re: Multiple disjoint sample sets?
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Xref: csiph.com comp.lang.python:36625

On 2013-01-11 14:15, Roy Smith wrote:
> I have a list of items.  I need to generate n samples of k unique items
> each.  I not only want each sample set to have no repeats, but I also
> want to make sure the sets are disjoint (i.e. no item repeated between
> sets).
>
> random.sample(items, k) will satisfy the first constraint, but not the
> second.  Should I just do random.sample(items, k*n), and then split the
> resulting big list into n pieces?  Or is there some more efficient way?
>
> Typical values:
>
> len(items) = 5,000,000
> n = 10
> k = 100,000
>
I don't know how efficient it would be, but couldn't you shuffle the
list and then use slicing to get the samples?