[R] substring if value starts with a character

[Ivan Calandra]

Hi Mat,

Try that:
gsub("[A-Za-z]", "", df$A)

This is a regular expression that looks for all characters (A to Z and a 
to z) and replaces it with nothing ("")
You will need to convert the column to numeric after this operation.

HTH,
Ivan

--
Ivan Calandra
University of Franche-Comté
Laboratoire Chrono-Environnement
Bureau ATER -107L
16, Route de Gray
25030 Besançon Cedex, France
ivan.calandra at univ-fcomte.fr
+33 (0) 381 66 20 60
http://chrono-environnement.univ-fcomte.fr/spip.php?article1830

Le 19/05/14 15:00, Mat a écrit :
> Hello togehter,
>
> i have a litte problem to convert a data.frame. My data.frame looks like
> this one
>        A
> 1  R5000
> 2  R4800
> 3  R4700
> 4  3500
> 5  3800
>
> I need now a command, which outputs all the numbers, without the character
> in front.
> The solution look like this one:
>      
>       A
> 1  5000
> 2  4800
> 3  4700
> 4  3500
> 5  3800
>
> Thanks.
>
> Best regards. Mat
>
>
>
> --
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