[R] Extract a 'data.frame$column' column name
Prof Brian Ripley
ripley at stats.ox.ac.uk
Mon May 3 13:40:15 CEST 2010
Hint: this is nothing to do with data frames ($ applies to lists). $
is an operator, so foo$Bar is a call. quote() stops it being
evaluated, [] selects the third of the elements (which are $, foo,
Bar) and as.character turns the name into a character string.
On Mon, 3 May 2010, adrien Penac wrote:
> I can't find how to get de column name from a data.frame dollar reference.
> To make it simple, I'd like to obtain "Bar" from a "foo$Bar" notation.
> I've tried col.names(foo$Bar), names(foo$Bar) and so on without sucess.
Brian D. Ripley, ripley at stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272866 (PA)
Oxford OX1 3TG, UK Fax: +44 1865 272595
More information about the R-help