R help - Jan 2008 - grep(): returning the matched value

Hi, 
 
I'm looking to use the grep function (or something else) to return the
matched pattern as opposed to the whole element. For example:
 
x <- c("pjhj24jhjhd")
grep("[[:digit:]]{2}", x, value=T) returns "people", whereas
I simply want "24".
 
Any help would be appreciated, 
 
Thanks, Aidan

	[[alternative HTML version deleted]]

Apologies, that should be 
 
grep("[[:digit:]]{2}", x, value=T) returns "pjhj24jhjhd"
 
obviously.  
 

________________________________

From: r-help-bounces@r-project.org on behalf of Macnamara, Aidan
Sent: Mon 1/14/2008 14:04
To: r-help@r-project.org
Subject: [R] grep(): returning the matched value



Hi,

I'm looking to use the grep function (or something else) to return the
matched pattern as opposed to the whole element. For example:

x <- c("pjhj24jhjhd")
grep("[[:digit:]]{2}", x, value=T) returns "people", whereas
I simply want "24".

Any help would be appreciated,

Thanks, Aidan

        [[alternative HTML version deleted]]

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	[[alternative HTML version deleted]]

Macnamara, Aidan wrote:
> Hi, 
>  
> I'm looking to use the grep function (or something else) to return the
matched pattern as opposed to the whole element. For example:
>  
> x <- c("pjhj24jhjhd")
> grep("[[:digit:]]{2}", x, value=T) returns "people",
whereas I simply want "24".
>  
> Any help would be appreciated, 
>  
> Thanks, Aidan
>   
Hi,

You need gsub, as in:

R> gsub("^.*([[:digit:]]{2}).*$","\\1", x )
[1] "24"

Cheers,

Romain

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