[R] looking for setdiff equivalent on dataset

[Hadley Wickham]

Here's one way, using a function from the plyr package:

TheLittleOne<-data.frame(cbind(c(2,3),c(2,3)))
TheBigOne<-data.frame(cbind(c(1,1,2),c(1,1,2)))

keys <- plyr:::join.keys(TheBigOne, TheLittleOne)

!(keys$x %in% keys$y)

TheBigOne[!(keys$x %in% keys$y), ]

Hadley

On Thu, Jul 29, 2010 at 1:38 PM, BaKaLeGuM <bakalegum at gmail.com> wrote:
> Hi everybody !
>
> little question.
>
> I have 2 dataset
>
> TheLittleOne<-data.frame(cbind(c(2,3),c(2,3)))
> TheBigOne<-data.frame(cbind(c(1,1,2),c(1,1,2)))
>
> And I would like to obtain the TheBigOne - TheLittleOne (the row in
> TheBigOne not in TheLittleOne
>
> The result should be:
> cbind(c(1,1),c(1,1))
>
>
> Have you any idea?
>
>
>
>
> PS : this function work.. but too slow and too much complex!..
>
> diff2data<-function(data1,data2){
> afaire<-setdiff(paste(data1[,1],data1[,2]),paste(data2[,1],data2[,2]))
> afaire<-data.frame(t(data.frame(strsplit(afaire," "))))
> if (sum(dim(afaire))
> !=0){afaire[,1]<-as.numeric(as.character(afaire[,1]));afaire[,2]<-as.numeric(as.character(afaire[,2]))}
> return(afaire)}
>
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>
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-- 
Assistant Professor / Dobelman Family Junior Chair
Department of Statistics / Rice University
http://had.co.nz/