[R] Differentiate alphanumeric vs numeric strings

[jim holtman]

The following will return the indices or the values of character
strings that are all numeric:

> x <- c("12345", "123AS23", "A123", "398457")
> grep("^[[:digit:]]*$", x)   # index
[1] 1 4
> grep("^[[:digit:]]*$", x, value=TRUE)   # values
[1] "12345"  "398457"
>



On Thu, Apr 24, 2008 at 10:39 PM, Farrel Buchinsky <fjbuch at gmail.com> wrote:
> I have a bunch of tables in a Microsoft Access database. An updated database
> is sent to me every week containing a new table. I know that is inefficient
> and weird but welcome to my life. I want to read the tables whose names are
> something such as "040207" but not the ones that have alphanumeric names
> such as "everyone". Using RODBC I am easily able to create a character
> vector of the names of the tables. Is there a function that can
> differentiate values consisting only of digits (numerics) as opposed to ones
> that contain letters (and perhaps digts as well)? I am sure there is. What
> is it and where should I have found it?
>
> --
> Farrel Buchinsky
> GrandCentral Tel: (412) 567-7870
>
>        [[alternative HTML version deleted]]
>
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>



-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem you are trying to solve?