Message-ID: <CA998306-C0F0-474D-855A-4764BF10B977@comcast.net>
Date: 2016-05-19T23:57:22Z
From: David Winsemius
Subject: Grep command
In-Reply-To: <b988efd2-cacd-60c3-0fd2-af7ed2b33794@gmail.com>
> On May 19, 2016, at 4:09 PM, Steven Yen <syen04 at gmail.com> wrote:
>
> What is a good way to grep multiple strings (say in a vector)? In the
> following, I grep ants, cats, and fox separately and concatenate them,
> is there a way to grep the trio in one action? Thanks.
>
> all<-c("ants","birds","cats","dogs","elks","fox"); all
> [1] "ants" "birds" "cats" "dogs" "elks" "fox"
> some<-c("ants","cats","fox"); some
> [1] "ants" "cats" "fox"
> j<-c(
> grep(some[1],all,value=F),
> grep(some[2],all,value=F),
> grep(some[3],all,value=F)); j; all[j]
> [1] 1 3 6
> [1] "ants" "cats" "fox"
j <- grep( paste0( some, collapse="|") , all ); j; all[j]
#----------
[1] 1 3 6
[1] "ants" "cats" "fox"
--
David Winsemius
Alameda, CA, USA