R help - Feb 2011 - Extract number from string

Dear R Users,

if I have a string as follows
x<-"jsda23tth"

How can I extract out 23 as a numeral?
I found
substr(x,5,6)
but, this doesnt work if the number of alphabets differ.

This is another example where the numbers need to be extracted.
x<-c("jsda23tth","fgd54fgd","j3ngh","gfdjh564")

any ideas?

This didnt work.
grep("[/d]",x)

Thanks,
Roy

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On Mon, Feb 7, 2011 at 9:37 AM, Roy Mathew <roymathew86 at gmail.com>
wrote:
> Dear R Users,
>
> if I have a string as follows
> x<-"jsda23tth"
>
> How can I extract out 23 as a numeral?
> I found
> substr(x,5,6)
> but, this doesnt work if the number of alphabets differ.
>
> This is another example where the numbers need to be extracted.
>
x<-c("jsda23tth","fgd54fgd","j3ngh","gfdjh564")
>
> any ideas?
>
> This didnt work.
> grep("[/d]",x)

Here are a couple of solutions:
> as.numeric(gsub("\\D", "", x))
[1]  23  54   3 564
> library(gsubfn)
> strapply(x, "\\d+", as.numeric, simplify = TRUE)
[1]  23  54   3 564



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