Re : Extract a 'data.frame$column' column name
See the describe functions in these packages: Hmisc pysch prettyR
On Mon, May 3, 2010 at 8:12 AM, adrien Penac <farfelu02 at yahoo.fr> wrote:
Thank a lot for these answers.
Some of you wondered why I needed
to do that!
In fact, I have not so big data.frame whith many
columns (98) and many of them are similar (many binary answers, some
factor data and a few quantitative datas).
As I am a lazy guy, I
wanted to do a sort of function that would apply some descriptive
statistics (and maybe some graphics) to each on them regarding to its
class.
And I wanted the results to be outputed as :
"Descriptive
statistics for : Bar"
results....
then, this would allow me to do a :
For (i in names(mydata)) desc(mydata[[i]])
In
fact, I was testing this function with a : desc(mydata$Bar)
where
desc was my lazy guy function defined as:
desc <- function(x) {
?print(paste("descriptive
statistics for ",x))
?if (is.factor(x)) {
? ?print("Raw count:")
? ?print(freq(x, total=T))
? ?print("Net counts:")
print(freq(x, total=T, exclude=NA))
? ?}
?else print(summary(x))
}
PS: freq is another function defined above
Regards
________________________________ De : Prof Brian Ripley <ripley at stats.ox.ac.uk> Cc : R-help at r-project.org Envoy? le : Lun 3 mai 2010, 13 h 40 min 15 s Objet : Re: [R] Extract a 'data.frame$column' column name as.character(quote(foo$Bar)[[3]]) [1] "Bar" 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, [[3]] selects the third of the elements (which are $, foo, Bar) and as.character turns the name into a character string. On Mon, 3 May 2010, adrien Penac wrote: Hello, ?I can't find how to get de column name from a data.frame dollar reference. To make it simple, I'd like to obtain "Bar" from a "foo$Bar" notation. I've tried col.names(foo$Bar), names(foo$Bar) and so on without sucess. Regards Blaise -- 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 ? ? ? ?[[alternative HTML version deleted]] ______________________________________________ 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.