Hello, If a matrix with 5 columns has been defined and the first two columns need to be sorted in ascending order, how can this be achieved whilst ensuring the other 3 columns data are in relative position to the sorted columns? Glen Jones [[alternative HTML version deleted]]
Have you considered "order"? The help file includes examples from
which you should be able to see how to do what you want.
hope this helps.
spencer graves
Jones, Glen R wrote:
>Hello,
>
>If a matrix with 5 columns has been defined and the first two columns
>need to be sorted in ascending order, how can this be achieved whilst
>ensuring the
>other 3 columns data are in relative position to the sorted columns?
>
>
>Glen Jones
>
> [[alternative HTML version deleted]]
>
>______________________________________________
>R-help at stat.math.ethz.ch mailing list
>https://stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html
>
>
Hi Glen,
-----Original Message-----
From: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Jones, Glen R
If a matrix with 5 columns has been defined and the first two columns
need to be sorted in ascending order, how can this be achieved whilst
ensuring the
other 3 columns data are in relative position to the sorted columns?
does the following example-code help you?
mymatrix should resemble the structure of your (original) matrix.
mymatrix2 is the new, sorted matrix.
mymatrix <- matrix(runif(80), ncol=5)
mymatrix[,1] <- sample(c(1,2), size=length(mymatrix[,1]), replace=TRUE)
mymatrix
mymatrix2 <- mymatrix[order(mymatrix[,1],mymatrix[,2]),]
mymatrix2
Best,
Roland
+++++
This mail has been sent through the MPI for Demographic Rese...{{dropped}}
Perhaps I read more into the question than others, but
I thought he was asking about a stable sort. If that is
the case, ?order says that the sort is stable except for method
"quick".
David L. Reiner
-----Original Message-----
From: Rau, Roland [mailto:Rau at demogr.mpg.de]
Sent: Monday, February 21, 2005 4:07 AM
To: Jones, Glen R; r-help at stat.math.ethz.ch
Subject: RE: [R] Sorting a matrix on two columns
Hi Glen,
-----Original Message-----
From: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Jones, Glen R
If a matrix with 5 columns has been defined and the first two columns
need to be sorted in ascending order, how can this be achieved whilst
ensuring the
other 3 columns data are in relative position to the sorted columns?
does the following example-code help you?
mymatrix should resemble the structure of your (original) matrix.
mymatrix2 is the new, sorted matrix.
mymatrix <- matrix(runif(80), ncol=5)
mymatrix[,1] <- sample(c(1,2), size=length(mymatrix[,1]), replace=TRUE)
mymatrix
mymatrix2 <- mymatrix[order(mymatrix[,1],mymatrix[,2]),]
mymatrix2
Best,
Roland
+++++
This mail has been sent through the MPI for Demographic
Rese...{{dropped}}
______________________________________________
R-help at stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide!
http://www.R-project.org/posting-guide.html