Split a data.frame
DF = data.frame(name = c('a', 'v', 'c'), val = 0); DF
## name val
## 1 a 0
## 2 v 0
## 3 c 0
split_str = c('a', 'c')
# If we assume that the values in split_str are ordered in the same order
as in the dataframe, then this might work.
offsets <- match(split_str, DF$name)
# Since you only want the rows in between
DF[diff(offsets), ]
## name val
## 2 v 0
Jim Holtman
Data Munger Guru
What is the problem that you are trying to solve?
Tell me what you want to do, not how you want to do it.
On Sat, May 19, 2018 at 7:58 AM, Rui Barradas <ruipbarradas at sapo.pt> wrote:
Hello,
Maybe something like the following.
splitDF <- function(data, col, s){
n <- nrow(data)
inx <- which(data[[col]] %in% s)
lapply(seq_along(inx), function(i){
k <- if(inx[i] < n) (inx[i] + 1):(inx[i + 1])
data[k, ]
})
}
splitDF(DF, "name", split_str)
Hope this helps,
Rui Barradas
On 5/19/2018 12:07 PM, Christofer Bogaso wrote:
Hi,
I am struggling to split a data.frame as will below scheme :
DF = data.frame(name = c('a', 'v', 'c'), val = 0); DF
split_str = c('a', 'c')
Now, for each element in split_str, R should find which row of DF contains
that element, and return DF with all rows starting from next row of the
corresponding element and ending with the preceding value of the next
element.
So in my case, I should see 2 data.frames
1st data-frame with name = 'v' (i.e. 2nd row of DF)
2nd data.frame with number_of_rows as 0 (as there is no row left after
'c')
Similarly if split_str = c('v'') then, my 2 data.frames will be
1st data.frame with name = 'a'
2nd data.frame with name = 'c'
Any idea how to efficiently implement above scheme would be highly
appreciated. I tried with split() function, however, it is not giving the
right answer.
Thanks,
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______________________________________________ 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/posti ng-guide.html and provide commented, minimal, self-contained, reproducible code.