[R] grep pattern

[Kang Min]

Thanks!

On May 21, 7:09 am, David Winsemius <dwinsem... at comcast.net> wrote:
> On May 20, 2011, at 11:57 AM, Kang Min wrote:
>
> > Hi all,
>
> > I'm trying to subset a pattern in a vector. Each argument has 6
> > letters, and I need those that start with Z and end with Z.
>
> > e.g.
> > x <- c("ZFHSJK", "ZFHJKZ","ZIOPWE","ZLKJSD","ZKFLPZ")
>
> > I've looked up other discussions but still can't seem to find the
> > answer.
>
> You may need to study the regex page a bit longer
>
> the "^" is the beginning of a string
> ".+" will math can arbitrarily long string of anything
> and "$" indicates the end of a string
>
>  > x <- c("ZFHSJK", "ZFHJKZ","ZIOPWE","ZLKJSD","ZKFLPZ")
>  > grep("^Z.+Z$", x)
> [1] 2 5
>  > grep("^Z.+Z$", x, value=TRUE)
> [1] "ZFHJKZ" "ZKFLPZ"
>
>
>
> > Thanks.
> > Kangmin
>
> > ______________________________________________
> > R-h... at r-project.org mailing list
> >https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html
> > and provide commented, minimal, self-contained, reproducible code.
>
> David Winsemius, MD
> West Hartford, CT
>
> ______________________________________________
> R-h... at r-project.org mailing listhttps://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guidehttp://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.