Sorry to hassle you, but I really need to get my code up and running.
Please can you therefore explain what a and v are?
Thank you,
Laura
On Wed, Sep 24, 2008 at 8:27 PM, Laura Bonnett
<[EMAIL PROTECTED]>wrote:
> Can I ask what a and v are?
>
> Thanks,
>
> Laura
>
>
> On Sat, Aug 23, 2008 at 11:41 AM, Robin Hankin <[EMAIL PROTECTED]> wrote:
>
>> Laura Bonnett wrote:
>>
>>> crosstable[,,expand[d,1],expand[d,2],expand[d,3],...expand[d,n]]
>>> crosstable is just a crosstabulation of an n+2-dimensional dataset and I
>>> am trying to pick out those that are in combination 'd' of expand. So for
>>> example, for 5-dimensional data using your example:
>>> Var1 Var2 Var3
>>> 1 1 1 1
>>> 2 2 1 1
>>> 3 3 1 1
>>> 4 1 2 1
>>> 5 2 2 1
>>> 6 3 2 1
>>> 7 1 1 2
>>> 8 2 1 2
>>> 9 3 1 2
>>> 10 1 2 2
>>> 11 2 2 2
>>> 12 3 2 2
>>> d refers to the row of the matrix above - d=2 is 2,1,1 so
>>> crosstable[,,2,1,1] would retrieve all the data where Var1 =2, Var2=1,
>>> Var3=1 and the two remaining variables are given in the crosstabulations for
>>> all values.
>>> Is that any better?
>>>
>>>
>> OK I think I understand. The magic package uses this type of
>> construction extensively, but not this particular one.
>>
>> It's trickier than I'd have expected.
>>
>> Try this:
>>
>> f <- function(a,v){
>> jj <-
>> sapply(dim(a)[seq_len(length(dim(a))-length(v))],seq_len,simplify=FALSE)
>> jj <- c(jj , as.list(v))
>> do.call("[" , c(list(a) , jj, drop=TRUE))
>> }
>>
>>
>>
>> [you will have to coerce the output from expand.grid() to a matrix in
>> order to extract a row from it]
>>
>>
>> HTH
>>
>> rksh
>>
>>
>>
>>
>>
>>
>>
>>
>> --
>> Robin K. S. Hankin
>> Senior Research Associate
>> Cambridge Centre for Climate Change Mitigation Research (4CMR)
>> Department of Land Economy
>> University of Cambridge
>> [EMAIL PROTECTED]
>> 01223-764877
>>
>>
>
[[alternative HTML version deleted]]
______________________________________________
R-help@r-project.org mailing list
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.
