Message-ID: <4957CDC0-976B-416C-846B-2D47EEE73E19@comcast.net>
Date: 2011-05-14T19:57:08Z
From: David Winsemius
Subject: Identify Objects that end with .f (and all caps)
In-Reply-To: <55a7610b6bbc40c8e4c852f007728c33.squirrel@webmail.uic.edu>
On May 14, 2011, at 3:38 PM, Sparks, John James wrote:
> Dear R Helpers,
>
> I am trying to find a way to identify all the objects in my
> environment
> that are all caps and then end with .f. I can do the all caps part
> pretty
> easily, but I have tried a number of variations on the \ and can't
> get a
> recognition of that operator. As a simple example
>
> A.f<-"foo1"
> AA.f<-"foo2"
> aa.f<-"foo3"
> A.a<-"foo4"
> ls()
> [1] "A.a" "A.f" "aa.f" "AA.f"
> temp1<-ls(pattern="[A-Z]")
> temp1
> [1] "A.a" "A.f" "AA.f"
>> temp2<-ls(pattern=\f)
> Error: unexpected input in "temp2<-ls(pattern=\"
You need to double the '\':
temp1<-ls(pattern="[A-Z]\\.f")
> temp1
[1] "A.f" "AA.f" "NYSE.A.f"
>
> The end goal is to isolate A.f and AA.f and not the others.
> In terms of just getting the 'ending with .f' portion, I have tried a
> number of variations in the pattern=\f, but can't get R to recognize
> what
> I want.
>
> Your guidance would be much appreciated.
> --John J. Sparks, Ph.D.
>
> ______________________________________________
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> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
David Winsemius, MD
West Hartford, CT