My apologies, I know that this is not a new problem, but I'm not sure how
to find the answer
I want to recursively loop over an object and trim trailing white space.
When I use this function on a list of data.frame I get output like this:
[1] "c(\" many spaces \", \" many spaces
\")" "c(\" many spaces
\", \" many spaces \")"
What should I do to recombine the results?
If anyone has a good way to search for this type of question, that would be
appreciated. I tried rseek.org with "recursive", but after wading
though
all the rpart references I didn't find something that seemed to help with
this problem.
Thank you very much.
trim <- function(x) {
if(length(x)>1) sapply(x[1], trim)
gsub("^[[:space:]]+|[[:space:]]+$", "", x)
}
tempobj = ' many spaces '
tempvec = c(tempobj, tempobj)
templist = list(tempvec, tempvec)
tempdf = data.frame(x = tempvec, y = tempvec)
trim(tempobj)
trim(tempvec)
trim(templist)
trim(tempdf)
Thank you,
Gene Leynes
_____________________________________________
*Data Scientist*
*Mobile: 312-498-7702
**http://www.linkedin.com/in/geneleynes
*
<http://goog_598053156>*http://geneorama.com/
<http://geneorama.com/%20>*
[[alternative HTML version deleted]]
"Recursively loop over an object" is a pretty meaningless phrase, since it depends entirely on the structure of the object. For example, a character vector is an object, and there is no need for any sort of recursion to do what you want for it. The following regex example trims trailing "spaces" (see ?regex for an exact definition). Adapt it to whatever structure you like, probably with apply type functions.> x <- c(" ab ","ab \t ","\t\t") > x[1] " ab " "ab \t " "\t\t"> sub("[[:space:]]+$","",x)[1] " ab" "ab" "" But note also that (e.g. S3) methods and is.list or is.recursive may be useful in a more general approach, something like (where deSpace(x) is a function with the above sub() expression): nospace <- function(x){ if(is.atomic(x))deSpace(x) else lapply(x, function(y)Recall(y)) ##?Recall for recursion } Note that this is completely untested, probably fails miserably and isn't what you want anyway, ... ;-) Good luck! Cheers, Bert On Fri, Aug 3, 2012 at 9:12 AM, Gene Leynes <gleynes at gmail.com> wrote:> My apologies, I know that this is not a new problem, but I'm not sure how > to find the answer > > I want to recursively loop over an object and trim trailing white space. > When I use this function on a list of data.frame I get output like this: > [1] "c(\" many spaces \", \" many spaces \")" "c(\" many spaces > \", \" many spaces \")" > > What should I do to recombine the results? > If anyone has a good way to search for this type of question, that would be > appreciated. I tried rseek.org with "recursive", but after wading though > all the rpart references I didn't find something that seemed to help with > this problem. > > Thank you very much. > > > trim <- function(x) { > if(length(x)>1) sapply(x[1], trim) > gsub("^[[:space:]]+|[[:space:]]+$", "", x) > } > > tempobj = ' many spaces ' > tempvec = c(tempobj, tempobj) > templist = list(tempvec, tempvec) > tempdf = data.frame(x = tempvec, y = tempvec) > > trim(tempobj) > trim(tempvec) > trim(templist) > trim(tempdf) > > > > > > Thank you, > Gene Leynes > _____________________________________________ > *Data Scientist* > *Mobile: 312-498-7702 > **http://www.linkedin.com/in/geneleynes > * > <http://goog_598053156>*http://geneorama.com/ <http://geneorama.com/%20>* > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.-- Bert Gunter Genentech Nonclinical Biostatistics Internal Contact Info: Phone: 467-7374 Website: http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm
Hello,
This seems to work.
trim2 <- function(x) {
if(is.atomic(x))
gsub("^[[:space:]]+|[[:space:]]+$", "", x)
else
sapply(x, function(y) trim2(y))
}
# Tests
trim2(tempobj)
trim2(tempvec)
trim2(templist)
trim2(tempdf)
# Extra test
templistlist <- list(templist, list(tempobj, tempdf))
trim2(templistlist)
Note, however, that the df is not returned as a df:
> class(trim2(tempdf))
[1] "matrix"
Hope this helps,
Rui Barradas
Em 03-08-2012 17:12, Gene Leynes escreveu:> My apologies, I know that this is not a new problem, but I'm not sure
how
> to find the answer
>
> I want to recursively loop over an object and trim trailing white space.
> When I use this function on a list of data.frame I get output like this:
> [1] "c(\" many spaces \", \" many spaces
\")" "c(\" many spaces
> \", \" many spaces \")"
>
> What should I do to recombine the results?
> If anyone has a good way to search for this type of question, that would be
> appreciated. I tried rseek.org with "recursive", but after
wading though
> all the rpart references I didn't find something that seemed to help
with
> this problem.
>
> Thank you very much.
>
>
> trim <- function(x) {
> if(length(x)>1) sapply(x[1], trim)
> gsub("^[[:space:]]+|[[:space:]]+$", "", x)
> }
>
> tempobj = ' many spaces '
> tempvec = c(tempobj, tempobj)
> templist = list(tempvec, tempvec)
> tempdf = data.frame(x = tempvec, y = tempvec)
>
> trim(tempobj)
> trim(tempvec)
> trim(templist)
> trim(tempdf)
>
>
>
>
>
> Thank you,
> Gene Leynes
> _____________________________________________
> *Data Scientist*
> *Mobile: 312-498-7702
> **http://www.linkedin.com/in/geneleynes
> *
> <http://goog_598053156>*http://geneorama.com/
<http://geneorama.com/%20>*
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at 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.