[R] intersecting rows of a matrix

From: dxc13 <dxc13_at_health.state.ny.us>
Date: Wed, 20 Feb 2008 15:45:29 -0800 (PST)


First, I would like to say thanks to John Fox for providing this segment of code to perform intersection for multiple sets: intersection <- function(x, y, ...){

 	if (missing(...)) intersect(x, y)
	else intersect(x, intersection(y, ...))

I want to execute this function on the rows of a matrix I have: Ik.mat.test <- matrix(c(2,3,6,1,2,6,6,1,2),byrow=T,nrow=3)
> Ik.mat.test

     [,1] [,2] [,3]

[1,]    2    3    6
[2,]    1    2    6
[3,]    6    1    2

I need to find a way to run the intersection function on the rows of this matrix. The result should be a vector containing 2, 6. This works, but I want to find a way to do this for any size matrix. intersection(Ik.mat.test[1,],Ik.mat.test[2,], Ik.mat.test[3,]) So, if the user supplied a matrix with any number of rows, I would like to be able to run this function. Any ideas? I have tried something like
do.call(intersection, list(Ik.mat.test[1,]: Ik.mat.test[3,])) but this doesnt work

Thanks in advance.

View this message in context: http://www.nabble.com/intersecting-rows-of-a-matrix-tp15601658p15601658.html
Sent from the R help mailing list archive at Nabble.com.

R-help_at_r-project.org mailing list
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
Received on Thu 21 Feb 2008 - 00:19:18 GMT

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.2.0, at Thu 21 Feb 2008 - 01:30:15 GMT.

Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help. Please read the posting guide before posting to the list.

list of date sections of archive