R help - Oct 2011 - splitting a string into words preserving blanks (using regex)

I would like to split a string into words at its blanks but also to preserve all
blanks.

Example:
	c(" some    words to split ") 
should become
	c(" ", "some", "   ", "	words", "
", "to" , " ", "split", " ")

I was not able to achieve this via strsplit() .
But I am not familiar with regular expressions.
Is there an easy way to do that using e.g. regex and strsplit?

Thanks
Mark
???????????????????????????????????????
Mark Heckmann
Blog: www.markheckmann.de
R-Blog: http://ryouready.wordpress.com

On Mon, Oct 24, 2011 at 9:46 AM, Mark Heckmann <mark.heckmann at gmx.de>
wrote:
> I would like to split a string into words at its blanks but also to
preserve all blanks.
>
> Example:
> ? ? ? ?c(" some ? ?words to split ")
> should become
> ? ? ? ?c(" ", "some", " ? ", "
words", " ", "to" , " ", "split",
" ")
>
> I was not able to achieve this via strsplit() .
> But I am not familiar with regular expressions.
> Is there an easy way to do that using e.g. regex and strsplit?
Try this:
> library(gsubfn)
> x <- " some    words to split "
> v <- strapply(x, "(\\s*)(\\S+)(\\s*)", c)[[1]]
> v[nchar(v) > 0]
[1] " "     "some"  "    "  "words"
" "     "to"    " "     "split" "
"


If you don't need the trailing space it can be further simplified:
> strapply(xx, "(\\s*)(\\S+)", c)[[1]]
[1] " "     "some"  "    "  "words"
" "     "to"    " "     "split"

or if you don't need the leading space it can be simplified like this:
> strapply(xx, "(\\S+)(\\s*)", c)[[1]]
[1] "some"  "    "  "words" " "    
"to"    " "     "split" " "

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Hi Mark,
here is a way using gsub to insert a "split marker" and strsplit.

strsplit(gsub("([[:alnum:]]+)","|\\1|",c(" some   
words to split "))[[1]]

cheers

Am 24.10.2011 15:46, schrieb Mark Heckmann:
> I would like to split a string into words at its blanks but also to
preserve all blanks.
> 
> Example:
> 	c(" some    words to split ") 
> should become
> 	c(" ", "some", "   ", "	words",
" ", "to" , " ", "split", " ")
> 
> I was not able to achieve this via strsplit() .
> But I am not familiar with regular expressions.
> Is there an easy way to do that using e.g. regex and strsplit?
> 
> Thanks
> Mark
> ???????????????????????????????????????
> Mark Heckmann
> Blog: www.markheckmann.de
> R-Blog: http://ryouready.wordpress.com
> 
> ______________________________________________
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