I thought that in the usual mathematical definition, combinations and
permutations differ: for permutations, order matters; for
combinations, it does not. Under this definition, the combinations of
3 things is just " i. 3 " - assuming we don't allow replacement? If
we do allow replacement, the permutations of 3 things are given by "
{3$<i.3 " and the combinations by something like " ~./:~&.>,{3$<i.3 ".
Does this seem right?
On Tue, Jun 26, 2012 at 12:51 PM, Raul Miller <rauldmil...@gmail.com> wrote:
> Note that the number of combinations and the number of permutions are the
> same.
>
> And, perm is just: ! A.&i. ]
>
> It seems like there ought to be a way of putting the permutations in 1
> to 1 correspondence with the combinations (to give us a concise
> expression for combinations).
>
> --
> Raul
>
> On Tue, Jun 26, 2012 at 12:41 PM, ed bierly <ebie...@gmail.com> wrote:
>> yes combinations not permutations
>> thought there might be a way that didn't loop
>> thank you for the references
>>
>> On Tue, Jun 26, 2012 at 12:30 PM, R.E. Boss <r.e.b...@planet.nl> wrote:
>>
>>> 4 comb 10
>>>
>>>
>>> R.E. Boss
>>>
>>>
>>> > -----Oorspronkelijk bericht-----
>>> > Van: programming-boun...@jsoftware.com [mailto:
>>> programming-boun...@jsoftware.com] Namens ed bierly
>>> > Verzonden: dinsdag 26 juni 2012 18:15
>>> > Aan: programming@jsoftware.com
>>> > Onderwerp: [Jprogramming] permutation list
>>> >
>>> > what is the best way to get this list of 210 vectors?
>>> >
>>> > 4!10
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--
Devon McCormick, CFA
^me^ at acm.
org is my
preferred e-mail
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