I think Duncan said that order and rank were inverses (if there are no ties). order() has period 2 so order(order(x)) is also rank(x) if there are no ties. E.g.,
> data.frame(x, o1=order(x), o2=order(order(x)), o3=order(order(order(x))), > o4=order(order(order(order(x)))), rank=rank(x)) x o1 o2 o3 o4 rank 1 2465 8 11 8 11 11.0 2 2255 9 10 9 10 10.0 3 2085 10 9 10 9 9.0 4 1545 7 8 7 8 8.0 5 1335 11 7 11 7 7.0 6 1210 6 6 6 6 6.0 7 920 5 4 5 4 4.0 8 210 4 1 4 1 1.5 9 210 3 2 3 2 1.5 10 505 2 3 2 3 3.0 11 1045 1 5 1 5 5.0 Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On > Behalf > Of Julio Sergio > Sent: Tuesday, April 16, 2013 11:10 AM > To: r-h...@stat.math.ethz.ch > Subject: Re: [R] I don't understand the 'order' function > > Julio Sergio <juliosergio <at> gmail.com> writes: > > > > > I thought I've understood the 'order' function, using simple examples like: > > Thanks to you all!... As Sarah said, what was damaged was my understanding ( > ;-) )... and as Duncan said, I was confusing 'order' with 'rank', > thanks! Now I understand the 'order' function. > > -Sergio > > ______________________________________________ > 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. ______________________________________________ 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.