[R] sort (all columns of) a matrix

[Daniel Malter]

I assume you want to sort the whole dataset (matrix) by ordering one column
in ascending order (and order all other columns appropriately).

a<-matrix(a<-c(1,3,4,6,6,4,6,56,4,64,86,39,4,2),length(a),2)
a

#sort by first column
a[order(a[,1]),]

#sort by second column
a[order(a[,2]),] 

#both give the same result here because the columns are identical

HTH,
Daniel


-------------------------
cuncta stricte discussurus
-------------------------

-----Ursprüngliche Nachricht-----
Von: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] Im
Auftrag von Kajan Saied
Gesendet: Thursday, October 08, 2009 12:51 PM
An: r-help at r-project.org
Betreff: [R] sort (all columns of) a matrix

Dear R-Help Team,

I have been trying to sort (all columns of) a matrix:

> a<-matrix(a<-c(1,3,4,6,6,4,6,56,4,64,86,39,4,2),length(a),2)
> a
      [,1] [,2]
 [1,]    1    1
 [2,]    3    3
 [3,]    4    4
 [4,]    6    6
 [5,]    6    6
 [6,]    4    4
 [7,]    6    6
 [8,]   56   56
 [9,]    4    4
[10,]   64   64
[11,]   86   86
[12,]   39   39
[13,]    4    4
[14,]    2    2
>
I would like to have the matrix sorted and the output should again be *a
matrix* with nrow=length(a) and ncol=2 just like (a) but only sorted.
Whatever I try (be it sort(), order()...) I receive a vector of
length(a)*2...

Could you please help me?

Best regards,

kajan

	[[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.