R help - Jun 2008 - Howto access V-base only column in a data frame

Hi,

Suppose I have the following data frame:

 V1 V2 V3 var
1 100 200 400 2.3
2 40.5 1.2  20.3
...

In this example the maximum V column is 3.
In my code there the column  number can be varied.

My question is how can I access data frame
from column V1 up to Vk (some "k" and excluding'var' column)?

- Gundala Viswanath
Jakarta - Indonesia

If you know the value of k then you could do the following:

goodNames <- paste("V",1:k,sep="")
ind <- which(colnames(df) %in% goodNames)
df[,ind]

(where df is your dataframe).

P.S. I won't be surprised if df[,goodNames] is all right too (have not
checked).

--- On Fri, 20/6/08, Gundala Viswanath <gundalav at gmail.com> wrote:
> From: Gundala Viswanath <gundalav at gmail.com>
> Subject: [R] Howto access V-base only column in a data frame
> To: r-help at stat.math.ethz.ch
> Received: Friday, 20 June, 2008, 1:27 PM
> Hi,
> 
> Suppose I have the following data frame:
> 
>  V1 V2 V3 var
> 1 100 200 400 2.3
> 2 40.5 1.2  20.3
> ...
> 
> In this example the maximum V column is 3.
> In my code there the column  number can be varied.
> 
> My question is how can I access data frame
> from column V1 up to Vk (some "k" and
> excluding'var' column)?
> 
> - Gundala Viswanath
> Jakarta - Indonesia
> 
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