[R] gsub and regex to tidy comma-limited values

[Wacek Kusnierczyk]

with the example below, i think the following solves your problem:

    text = ',,,apple,,orange,,,,,lemon,strawberry,,,,'
    gsub('^,+|,+(?=,)|,+$', '', text, perl=TRUE)

vQ

Tom wrote:
> sub(",$","",gsub("^,*|,*$|(,)*", "\\1",
> ",,,apple,,orange,,,,,lemon,strawberry,,,,"))
>
> It may not be the best solution, but it was my first thought
>
> Tom
>
> ----- Original Message ----- From: "Daren Tan" <darentan76 at gmail.com>
> To: <r-help at r-project.org>
> Sent: Saturday, March 14, 2009 6:42 PM
> Subject: [R] gsub and regex to tidy comma-limited values
>
>
>> I am cleaning up comma-limited values, so that only one comma
>> separates each value. Using the example below, as much as I try with
>> regex, I can't remove the last comma. I hope to have a one-liner
>> solution, if possible.
>>
>> gsub("^,*|,*$|(,)*", "\\1", ",,,apple,,orange,,,,,lemon,strawberry,,,,")
>> [1] "apple,orange,lemon,strawberry,"
>>
>> ______________________________________________
>> 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.
>
> ______________________________________________
> 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.


-- 
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Wacek Kusnierczyk, MD PhD

Email: waku at idi.ntnu.no
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