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From: Dr. Bruno Campanini on 23 May 2010 03:17
Subsets[Range[90],{5}] should print all the
Binomial[90,5] = 43 949 268 combinations.

On my PC (4gb RAM) Mathematica 7.0 claims
"Not enough memory".

By the way, I only need to print some thousands
of these combinations, then Subsets[Range[90],{5}, 3000]
works fine.
But it prints the first 3000 combination in lexicographic
order. How to get 3000 random out of 43 949 268, not
ordered?

Bruno

From: M.Roellig on 23 May 2010 07:20
Hi,

You could use RandomSample

RandomSample[Subsets[Range[90], {5}], 3000]

Cheers,

Markus


On 23 Mai, 09:17, "Dr. Bruno Campanini" <cmp...(a)gmail.com> wrote:
> Subsets[Range[90],{5}] should print all the
> Binomial[90,5] = 43 949 268 combinations.
>
> On my PC (4gb RAM) Mathematica 7.0 claims
> "Not enough memory".
>
> By the way, I only need to print some thousands
> of these combinations, then Subsets[Range[90],{5}, 3000]
> works fine.
> But it prints the first 3000 combination in lexicographic
> order. How to get 3000 random out of 43 949 268, not
> ordered?
>
> Bruno


From: Ray Koopman on 23 May 2010 07:20
On May 23, 12:17 am, "Dr. Bruno Campanini" <cmp...(a)gmail.com> wrote:
> Subsets[Range[90],{5}] should print all the
> Binomial[90,5] = 43 949 268 combinations.
>
> On my PC (4gb RAM) Mathematica 7.0 claims
> "Not enough memory".
>
> By the way, I only need to print some thousands
> of these combinations, then Subsets[Range[90],{5}, 3000]
> works fine.
> But it prints the first 3000 combination in lexicographic
> order. How to get 3000 random out of 43 949 268, not
> ordered?
>
> Bruno

This has a 90% chance of Length[s] being 3000.
It's very fast. Just keep trying until you get it.

Dimensions[s = Union(a)Table[Sort(a)RandomSample[Range(a)90,5],{3000}]]

From: Patrick Scheibe on 23 May 2010 07:20
Hi,

data = RandomSample[Subsets[Range[90], {5}], 3000];

works fine here: "7.0 for Linux x86 (64-bit) (February 18, 2009)"

Cheers
Patrick

On Sun, 2010-05-23 at 03:17 -0400, Dr. Bruno Campanini wrote:
> Subsets[Range[90],{5}] should print all the
> Binomial[90,5] = 43 949 268 combinations.
>
> On my PC (4gb RAM) Mathematica 7.0 claims
> "Not enough memory".
>
> By the way, I only need to print some thousands
> of these combinations, then Subsets[Range[90],{5}, 3000]
> works fine.
> But it prints the first 3000 combination in lexicographic
> order. How to get 3000 random out of 43 949 268, not
> ordered?
>
> Bruno
>


From: Scott Hemphill on 25 May 2010 06:32
Patrick Scheibe <pscheibe(a)trm.uni-leipzig.de> writes:

> Hi,
>
> data = RandomSample[Subsets[Range[90], {5}], 3000];
>
> works fine here: "7.0 for Linux x86 (64-bit) (February 18, 2009)"

Yes, I have the same version. After execution, MathKernel was using
3505MB of virtual memory.

Scott


> On Sun, 2010-05-23 at 03:17 -0400, Dr. Bruno Campanini wrote:
>> Subsets[Range[90],{5}] should print all the
>> Binomial[90,5] = 43 949 268 combinations.
>>
>> On my PC (4gb RAM) Mathematica 7.0 claims
>> "Not enough memory".
>>
>> By the way, I only need to print some thousands
>> of these combinations, then Subsets[Range[90],{5}, 3000]
>> works fine.
>> But it prints the first 3000 combination in lexicographic
>> order. How to get 3000 random out of 43 949 268, not
>> ordered?
>>
>> Bruno
>>
>
>

--
Scott Hemphill hemphill(a)alumni.caltech.edu
"This isn't flying. This is falling, with style." -- Buzz Lightyear

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