[R] Getting all possible combinations

[Spencer Graves]

On 2017-08-23 11:35 AM, Bert Gunter wrote:
> ummm, Ista, it's 2^n.


       or (2^n-1) if the empty set is not considered as a "combination" 
;-)  spencer
>
> Cheers,
> Bert
>
>
> Bert Gunter
>
> "The trouble with having an open mind is that people keep coming along
> and sticking things into it."
> -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )
>
>
> On Wed, Aug 23, 2017 at 8:52 AM, Ista Zahn <istazahn at gmail.com> wrote:
>> On Wed, Aug 23, 2017 at 11:33 AM, Christofer Bogaso
>> <bogaso.christofer at gmail.com> wrote:
>>> Hi again,
>>>
>>> I am exploring if R can help me to get all possible combinations of
>>> members in a group.
>>>
>>> Let say I have a group with 5 members : A, B, C, D, E
>>>
>>> Now I want to generate all possible unique combinations with all
>>> possible lengths from that group e.g.
>>>
>>> 1st combination : A
>>> 2nd combination : B
>>> .....
>>> 5th combination : E
>>> 6th combination : A, B
>>> 7th combination : B, C
>>> ....
>>> last combination: A, B, C, D, E
>>>
>>> Ideally, I have a fairly large group so am looking for some
>>> programmatic way to generate all possible combinations.
>> Be careful, the number of combinations grows pretty quickly. You can
>> calculate the number ahead of time with
>>
>> sum(choose(n, 1:n))
>>
>> where n is the number of values in your group.
>>
>> --Ista
>>
>>> Any help will be highly appreciated.
>>>
>>> Thanks for your time.
>>>
>>> ______________________________________________
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>>> and provide commented, minimal, self-contained, reproducible code.
>> ______________________________________________
>> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.