Dear Jim, This works for your small example. I was not exactly sure what you were sorting on. In my example, I sum all values at each level of the third dimension and sort by that sum. Of course, if there are many levels or the 2 dimensions being summed are quite large, this will be quite computationally inefficient. I also show how you could sort but just the value in cell [1, 1, i] where i moves across all levels of the third dimension.
## Your data x <- array(c(9, 9, 7, 9, 6, 5, 4, 6, 2, 1, 3, 2), dim = list(2, 2, 3)) ## sorting by sum dims 1&2 at each level of 3rd x[ , , order(apply(x, 3, sum))] ## sorting by cell [1, 1] at each level of 3rd x[ , , order(x[1, 1, ])] HTH, Josh On Fri, Feb 18, 2011 at 5:01 AM, Maas James Dr (MED) <j.m...@uea.ac.uk> wrote: > I'm attempting to sort a 3 dimensional array that looks like this >> x > , , 1 > [,1] [,2] > [1,] 9 9 > [2,] 7 9 > , , 2 > [,1] [,2] > [1,] 6 5 > [2,] 4 6 > , , 3 > [,1] [,2] > [1,] 2 1 > [2,] 3 2 > > Such that it ends up like this .... >> y > , , 1 > [,1] [,2] > [1,] 2 1 > [2,] 3 2 > , , 2 > [,1] [,2] > [1,] 6 5 > [2,] 4 6 > , , 3 > [,1] [,2] > [1,] 9 9 > [2,] 7 9 > > I think this is sorting across the third dimension but several attempts using > either the sort or apply functions have not worked. Any and all suggestions > most welcome. Thanks > > J > > =============================== > Dr. Jim Maas > University of East Anglia > > > [[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. > -- Joshua Wiley Ph.D. Student, Health Psychology University of California, Los Angeles http://www.joshuawiley.com/ ______________________________________________ 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.
