[R] How to retrieve a column name of a data frame

[R. Michael Weylandt]

I'd use something like

which(df == "b", arr.ind = TRUE)

which, gives the column number in the second spot; this gives you

colnames(df)[which(df == "b", arr.ind = TRUE)[2]]

Michael


On Thu, Feb 2, 2012 at 11:00 AM, ikuzar <razuki at hotmail.fr> wrote:
> Sorry, it was not clear:
>
> my program have to return column name  corresponding to a value, for example
> 'b' (so, the corresponding column is c1)
> How to retrieve c1 ?
> Thanks
>
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