[R] Addressing Columns in a Data Frame

[Michael Weylandt]

On Feb 9, 2013, at 1:40 PM, Lorenzo Isella <lorenzo.isella at gmail.com> wrote:

> Dear All,
> Probably a one liner, but I am banging my head against the floor.
> Consider the following
> 
> DF <- data.frame(
>   x=1:10,
>   y=10:1,
>   z=rep(5,10),
>   a=11:20
> )
> 
> mn<-names(DF)
> 
> but then I cannot retrieve a column by doing e.g,
> 
> DF$mn[2]
> 

$ doesn't evaluate it's arguments so I think you want something like: DF[[mn[2]]] or DF[,mn[2]] 

Cheers,
MW



> I tried to play with the quotes and so on, but so far with no avail.
> Any suggestion is welcome.
> Cheers
> 
> Lorenzo
> 
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