[R] question: how to select a column from a dataframe in a function

[Petr PIKAL]

Hi

> 
> Hi,
> 
> I am creating a function and ran into the problem of selecting a column
> from a dataset. It seems as though the $ function (as in 
data$columnname)
> does not apply in the function. In simplified version:
> 
> This works:
>  testf2<-function(data,columnnumber){print(data[,columnnumber])}
> 
> But this doesn't:
> testf<-function(data,column){print(data$column)}
> 
> Even though the first solution works, I would like to be able to insert 
the
> columnname in the function, instead of the columnnumber. How do I do 
that?

Not sure if you get any answer yet.

testf2<-function(data,columnname){print(data[,columnname])}

Petr

> 
> Thank you in advance,
> 
> Julia
> 
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