I have the following command:
length(
grep("\.a\.", names(temp)))
where temp is a vector with names
I want to count the number of entries that contain the
sequence of characters ".a.". However, R seems to
return all entries that contain "a" (every entry
contains "." in this example).
How should I fix this? Thanks
__________________________________
How about the following:
> tst <- c(".a.", "asdf")
> sum(regexpr("\\.a\\.", tst)>0)
[1] 1
hope this helps. spencer graves
K Fung wrote:
>I have the following command:
>
>length(
> grep("\.a\.", names(temp)))
>
>where temp is a vector with names
>
>I want to count the number of entries that contain the
>sequence of characters ".a.". However, R seems to
>return all entries that contain "a" (every entry
>contains "." in this example).
>
>How should I fix this? Thanks
>
>
>__________________________________
>
>______________________________________________
>R-help at stat.math.ethz.ch mailing list
>https://www.stat.math.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html
>
>
Thanks Your suggestion works. The fix is to use double \\ rather than single \. Changing this makes grep work as well. --- Spencer Graves <spencer.graves at pdf.com> wrote:> How about the following: > > > tst <- c(".a.", "asdf") > > sum(regexpr("\\.a\\.", tst)>0) > [1] 1 > > hope this helps. spencer graves > > K Fung wrote: > > >I have the following command: > > > >length( > > grep("\.a\.", names(temp))) > > > >where temp is a vector with names > > > >I want to count the number of entries that contain > the > >sequence of characters ".a.". However, R seems to > >return all entries that contain "a" (every entry > >contains "." in this example). > > > >How should I fix this? Thanks > > > > > >__________________________________ > > > >______________________________________________ > >R-help at stat.math.ethz.ch mailing list > >https://www.stat.math.ethz.ch/mailman/listinfo/r-help > >PLEASE do read the posting guide! > http://www.R-project.org/posting-guide.html > > > > >__________________________________