On Dec 6, 2007 6:11 AM, Martin Maechler <[EMAIL PROTECTED]> wrote: > >>>>> "MS" == Marc Schwartz <[EMAIL PROTECTED]> > >>>>> on Wed, 05 Dec 2007 12:43:50 -0600 writes: > > [............] > > MS> Martin, > > MS> Thanks for the corrections. In hindsight, now seeing the intended use > of > MS> ecdf() in the fashion you describe above, it is now clear that my > MS> approach in response to David's query was un-needed and "over the top". > MS> "Yuck" is quite appropriate... :-) > > MS> As I was going through this "exercise", it did seem overly complicated, > MS> given R's usual elegant philosophy about such things. I suppose if I > had > MS> looked at the source for plot.stepfun(), it would have been more > evident > MS> as to how the y values are acquired. > > MS> In reviewing the examples in ?ecdf, I think that an example using > MS> something along the lines of the discussion here more explicitly, would > MS> be helpful. It is not crystal clear from the examples, that one can use > MS> ecdf() in this fashion, though the use of "12 * Fn(tt)" hints at it. > > MS> Perhaps: > > MS> ##-- Simple didactical ecdf example: > MS> x <- rnorm(12) > MS> Fn <- ecdf(x) > MS> Fn > MS> Fn(x) # returns the percentiles for x > MS> ... > > Thank you, Marc for the above proposal, to make the examples > more "crystal clear" :-) > I've now amended the R-devel version of help(ecdf) accordingly.
Since the above does not actually reproduce percentrank in the case of ties, the change that would facilitate this particularly would be to add a ties = "excelpercentrank" to approx. See my solution earlier in this thread. ______________________________________________ R-help@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.
