Hi,
May be this helps:
c1<-combn(seq_len(ncol(m)),2)
mat1<- matrix(0,ncol=3,nrow=3,dimnames=list(colnames(m),colnames(m)))
vec1<-unlist(lapply(seq_len(ncol(c1)),function(i) {m1<-m[,c1[,i]];
length(which(m1[,1]!=0 & m1[,2]!=0)) }))
mat1[lower.tri(mat1)]<-vec1
mat1
# rs1 rs2 rs3
#rs1 0 0 0
#rs2 1 0 0
#rs3 2 1 0
#Converting to sparseMatrix
library(Matrix)
mat2<-as(mat1,"sparseMatrix")
#or
mat2<-Matrix(mat1,sparse=TRUE)
3 x 3 sparse Matrix of class "dtCMatrix"
# rs1 rs2 rs3
#rs1 . . .
#rs2 1 . .
#rs3 2 1 .
A.K.
----- Original Message -----
From: Hermann Norpois <hnorp...@gmail.com>
To: r-help <r-help@r-project.org>
Cc:
Sent: Wednesday, May 15, 2013 3:57 PM
Subject: [R] matrix - pairwise comparison of columns
Hello,
I would like to do something with a matrix:
1) The columns should be compared pairwise.
2) And the result should be a matrix.
I try to illustrate the problem with a testset.
> m
rs1 rs2 rs3
[1,] 1 1 1
[2,] 0 1 0
[3,] 2 0 1
> dput (m)
structure(c(1, 0, 2, 1, 1, 0, 1, 0, 1), .Dim = c(3L, 3L), .Dimnames = list(
NULL, c("rs1", "rs2", "rs3")))
> which (m[,1] !=0&m[,2] != 0) #How many rows between two columns that are
both non zero
How can I automate the pairwise which-statement?
As result I would like to have a matrix like this
rs1 rs2 rs3
rs1
rs2 1
rs3 2 1
Is there a tool in R that helps?
Thanks
Hermann
[[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.
______________________________________________
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.
