In a regular expression, '.' matches any character, which will be the first one. If you want to match a period, you have to escape it:
> f="a,[EMAIL PROTECTED]:" #define an arbitrary test string > regexpr('.',f) [1] 1 attr(,"match.length") [1] 1 > regexpr('\\.',f) [1] 4 attr(,"match.length") [1] 1 > On Tue, Apr 15, 2008 at 6:27 AM, Jonathan Williams <[EMAIL PROTECTED]> wrote: > Dear R Helpers, > > I am running R 2.6.2 on a Windows XP machine. > > I am trying to use regexpr to locate full stops in strings, but, without > success. > > Here an example:- > > f="a,[EMAIL PROTECTED]:" #define an arbitrary test string > regexpr(',',f) #find the occurrences of ',' in f - should be one at location > 2 > # and this is what regexpr finds > #[1] 2 > #attr(,"match.length") > #[1] 1 > > regexpr('@',f) #find occurrences of '@' in f - should be one at location 6 > # and this is what regexpr finds > #[1] 6 > #attr(,"match.length") > #[1] 1 > > regexpr('.',f) #find the occurrences '.' in f - should be one at location 4 > # but regexpr gives 1 at location 1 > #[1] 1 > #attr(,"match.length") > #[1] 1 > > Sorry if I am missing something obvious. I'd be very grateful if someone > would > please show me how to use regexpr to locate '.' in my string! > > Thanks, > > Jonathan Williams > > ______________________________________________ > 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. > -- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem you are trying to solve? ______________________________________________ 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.