[R] colname refered by a variable

[Ivan Calandra]

Or simpler:
df[, paste("A","C",sep="")]
df[[paste("A","C",sep="")]]

Or:
x <- paste("A","C",sep="")
df[,x]
df[[x]]

Btw, you don't need to use cbind(), data.frame() does it already

Ivan

Le 12/3/2010 08:21, Santosh Srinivas a écrit :
> try this ..
>
> df[,colnames(df)==paste("A","C",sep="")]
>
> On Fri, Dec 3, 2010 at 12:05 PM, Yuan Jian<jayuan2008 at yahoo.com>  wrote:
>> Hello,
>>
>> I tried to use a variable to refer colname, but I got error, could anyone give me advice?
>>
>>> df=data.frame(cbind(AB=1:3,AC=3:5))
>>> df$AC
>> [1] 3 4 5
>>> df$paste("A","C",sep="")
>> Error: attempt to apply non-function
>>
>> thanks
>> Jian
>>
>>
>>
>>
>>         [[alternative HTML version deleted]]
>>
>>
>> ______________________________________________
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>> and provide commented, minimal, self-contained, reproducible code.
>>
>>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>

-- 
Ivan CALANDRA
PhD Student
University of Hamburg
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ivan.calandra at uni-hamburg.de

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