Sort matrix by column 1 ascending then by column 2 decending
Nice. Works perfectly.
On Wed, May 27, 2009 at 2:03 PM, Henrique Dallazuanna <wwwhsd at gmail.com> wrote:
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 <paulgeeleher at 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
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-- Henrique Dallazuanna Curitiba-Paran?-Brasil 25? 25' 40" S 49? 16' 22" O
Paul Geeleher School of Mathematics, Statistics and Applied Mathematics National University of Ireland Galway Ireland