Try this: cbind(sort(x[,1]), unlist(tapply(x[,2], x[,1], sort, decreasing = T)))
On Wed, May 27, 2009 at 9:39 AM, Paul Geeleher <paulgeele...@gmail.com>wrote: > I've got a matrix with 2 columns and n rows. I need to sort it first > by the values in column 1 ascending. Then for values which are the > same in column 1, sort by column 2 decending. For example: > > 2 .5 > 1 .3 > 1 .5 > 3 .2 > > Goes to: > > 1 .5 > 1 .3 > 2 .5 > 3 .2 > > This is easy to do in spreadsheet programs but I can't seem to work > out how to do it in R and haven't been able to find a solution > anywhere. > > > Thanks! > > -Paul. > > -- > Paul Geeleher > School of Mathematics, Statistics and Applied Mathematics > National University of Ireland > Galway > Ireland > > ______________________________________________ > 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. > -- Henrique Dallazuanna Curitiba-Paraná-Brasil 25° 25' 40" S 49° 16' 22" O [[alternative HTML version deleted]]
______________________________________________ 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.
