R help - Jan 2009 - splitting a string / finding a numeric value within a string

Hi,

I have this variable;


x <- c("test_01.log")


and I want to extract the number (01) out of the variable.
So that I get;

 > x
[1] 1



I tried strsplit, but I don't know how to refer to the result.

Can someone help me with that?
	[[alternative HTML version deleted]]

Dear Jörg,
Try this:
> gsub("^.*['_']|[.].*$", "",
"test_01.log")
[1] "01"
> as.numeric(gsub("^.*['_']|[.].*$", "",
"test_01.log"))
[1] 1


HTH,

Jorge


On Fri, Jan 16, 2009 at 11:00 PM, Jörg Groß <joerg@licht-malerei.de>
wrote:
> Hi,
>
> I have this variable;
>
>
> x <- c("test_01.log")
>
>
> and I want to extract the number (01) out of the variable.
> So that I get;
>
>  > x
> [1] 1
>
>
>
> I tried strsplit, but I don't know how to refer to the result.
>
> Can someone help me with that?
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@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.
>
	[[alternative HTML version deleted]]

The first one replaces non-numerics with the empty string
and the second one returns numerics directly:

gsub("[^0-9]", "", "test_01.log")

# or
library(gsubfn)
strapply("test_01.log", "[0-9]+")[[1]]

On Fri, Jan 16, 2009 at 11:00 PM, J?rg Gro? <joerg at licht-malerei.de>
wrote:
> Hi,
>
> I have this variable;
>
>
> x <- c("test_01.log")
>
>
> and I want to extract the number (01) out of the variable.
> So that I get;
>
>  > x
> [1] 1
>
>
>
> I tried strsplit, but I don't know how to refer to the result.
>
> Can someone help me with that?
>        [[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.
>