[R] aggregate combination data

[Rui Barradas]

Hello,

This will give you a list of 19 elements, each element k is a matrix of 
all combinations of 19 taken k at a time.

cmb <- lapply(seq_len(nrow(dat)), function(k) combn(nrow(dat), k))
d <- dat[["d"]]
lapply(cmb, function(cc) apply(cc, 2, function(j) d[j]))


Hope this helps,

Rui Barradas
Em 14-11-2012 13:32, catalin roibu escreveu:
> I want to aggregate all values of diameter after the combination between
> plots. For example all diameter (d) values for combination of n plots taken
> by k.
>
>
> On 14 November 2012 15:28, Rui Barradas <ruipbarradas at sapo.pt> wrote:
>
>> Hello,
>>
>> You forgot to Cc the list.
>> As for your question, you want all possible combinations of rows? For all
>> possible values of k in 1:19?
>>
>>> sum(sapply(1:19, function(k) choose(19, k)))
>> [1] 524287
>>
>> Or you want to split the data.frame by plot and the have all possible
>> combinations?
>>
>>> sum(sapply(1:10, function(k) choose(10, k)))
>> [1] 1023
>>> sum(sapply(1:9, function(k) choose(9, k)))
>> [1] 511
>>
>> Rui Barradas
>> Em 14-11-2012 11:31, catalin roibu escreveu:
>>
>>   I don't want to sum the data from all combination. I want to group
>>> (aggregate) the all values resulted from all combination possible.
>>> plot d
>>> 1 14
>>> 1 13
>>> 1 12
>>> 1 14
>>> 1 18
>>> 1 20
>>> 1 21
>>> 1 43
>>> 1 108
>>> 1 43
>>> 2 41
>>> 2 61
>>> 2 83
>>> 2 61
>>> 2 84
>>> 2 45
>>> 2 21
>>> 2 12
>>> 2 11
>>>
>>>
>>> On 14 November 2012 13:25, Rui Barradas <ruipbarradas at sapo.pt> wrote:
>>>
>>>   Hello,
>>>> Please use ?dput to post your data.
>>>>
>>>> dput(MyData)  # paste the output of this in a post.
>>>>
>>>> And you must be more clear, what does "aggregate" mean? To sum? In the
>>>> mean time see
>>>>
>>>> ?combn
>>>>
>>>> Hope this helps,
>>>>
>>>> Rui Barradas
>>>> Em 14-11-2012 11:11, catalin roibu escreveu:
>>>>
>>>>   Dear R users,
>>>>> I want to aggregate all *d *data from  all combination of n *plots*
>>>>> taken
>>>>>
>>>>> by k.
>>>>> Thank very much!
>>>>>
>>>>> My data is like that:
>>>>>               plot              d  1 14  1 13  1 12  1 14  1 18  1 20  1
>>>>> 21
>>>>>    1
>>>>> 43  1 108  1 43  2 41  2 61  2 83  2 61  2 84  2 45  2 21  2 12  2 11
>>>>>    ...  100
>>>>>          10
>>>>> 100       12
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>