HI,
Try this:
set.seed(15)
lst<-
list(matrix(sample(1:15,20,replace=TRUE),ncol=5),matrix(sample(4:20,20,replace=TRUE),ncol=5),matrix(sample(8:25,20,replace=TRUE),ncol=5))
library(abind)
arr1<-abind(lst,along=3)
apply(arr1,c(1,2),median)
#??? [,1] [,2] [,3] [,4] [,5]
#[1,]?? 17?? 13?? 19?? 12??? 7
#[2,]?? 16?? 15?? 12?? 11?? 15
#[3,]?? 15?? 13?? 12?? 12??? 9
#[4,]?? 10??? 6?? 10?? 15?? 12
#or
library(plyr)
?aaply(laply(lst,as.matrix),c(2,3),median)
#?? X2
#X1?? 1? 2? 3? 4? 5
#? 1 17 13 19 12? 7
#? 2 16 15 12 11 15
#? 3 15 13 12 12? 9
#? 4 10? 6 10 15 12
A.K.
----- Original Message -----
From: Lucas Holland <hollandlucas at gmail.com>
To: "r-help at R-project.org" <r-help at r-project.org>
Cc:
Sent: Friday, March 22, 2013 5:17 PM
Subject: [R] Median across matrices
Hey all,
I have a list of matrices. I'd like to calculate the median across all those
matrices for each element. What I'd like to end up with is a matrix
containing the median of all [1,1] [1,2] etc. elements across all matrices.
Is there a concise way of doing that?
Thanks!
______________________________________________
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.