Dear
I use sm2vec from package corpcor to puts the lower triagonal entries
of a symmetric matrix (matrix A) into a vector. However, sm2vec goes
downward (columnwise, vector B), but I would like it to go across
(rowwise). So I define a vector to re-map the vector (vector C). This
works. But is there a short-cut (simpler way)? Thank you.
> A<-cor(e); A
[,1] [,2] [,3] [,4] [,5] [,6]
[1,] 1.00000000 0.5240809 0.47996616 0.11200672 -0.1751103 -0.09276455
[2,] 0.52408090 1.0000000 0.54135982 -0.15985028 -0.2627738 -0.14184545
[3,] 0.47996616 0.5413598 1.00000000 -0.06823105 -0.2046897 -0.23815967
[4,] 0.11200672 -0.1598503 -0.06823105 1.00000000 0.2211311 0.08977677
[5,] -0.17511026 -0.2627738 -0.20468966 0.22113112 1.0000000 0.23567235
[6,] -0.09276455 -0.1418455 -0.23815967 0.08977677 0.2356724 1.00000000
> B<-sm2vec(A); B
[1] 0.52408090 0.47996616 0.11200672 -0.17511026 -0.09276455
[6] 0.54135982 -0.15985028 -0.26277383 -0.14184545 -0.06823105
[11] -0.20468966 -0.23815967 0.22113112 0.08977677 0.23567235
> jj<-c(1,2,6,3,7,10,4,8,11,13,5,9,12,14,15)
> C<-B[jj]; C
[1] 0.52408090 0.47996616 0.54135982 0.11200672 -0.15985028
[6] -0.06823105 -0.17511026 -0.26277383 -0.20468966 0.22113112
[11] -0.09276455 -0.14184545 -0.23815967 0.08977677 0.23567235
Package corpcor: Putting symmetric matrix entries in vector
4 messages · Steven Yen, David Winsemius, Peter Langfelder
On Jan 30, 2015, at 3:03 PM, Steven Yen wrote:
Dear I use sm2vec from package corpcor to puts the lower triagonal entries of a symmetric matrix (matrix A) into a vector. However, sm2vec goes downward (columnwise, vector B), but I would like it to go across (rowwise). So I define a vector to re-map the vector (vector C). This works. But is there a short-cut (simpler way)? Thank you.
What about using this sequence to instead extract from the original A-Matrix: c(2, unlist( sapply( 3:6, function(n) c( n, n+6*seq(n-2) ) )) ) [1] 2 3 9 4 10 16 5 11 17 23 6 12 18 24 30
idx <- c(2, unlist( sapply( 3:6, function(n) c( n, n+6*seq(n-2) ) )) ) A[idx]
[1] 0.52408090 0.47996616 0.54135982 0.11200672 -0.15985028 -0.06823105 [7] -0.17511030 -0.26277380 -0.20468970 0.22113110 -0.09276455 -0.14184545 [13] -0.23815967 0.08977677 0.23567235
A<-cor(e); A
[,1] [,2] [,3] [,4] [,5] [,6] [1,] 1.00000000 0.5240809 0.47996616 0.11200672 -0.1751103 -0.09276455 [2,] 0.52408090 1.0000000 0.54135982 -0.15985028 -0.2627738 -0.14184545 [3,] 0.47996616 0.5413598 1.00000000 -0.06823105 -0.2046897 -0.23815967 [4,] 0.11200672 -0.1598503 -0.06823105 1.00000000 0.2211311 0.08977677 [5,] -0.17511026 -0.2627738 -0.20468966 0.22113112 1.0000000 0.23567235 [6,] -0.09276455 -0.1418455 -0.23815967 0.08977677 0.2356724 1.00000000
B<-sm2vec(A); B
[1] 0.52408090 0.47996616 0.11200672 -0.17511026 -0.09276455 [6] 0.54135982 -0.15985028 -0.26277383 -0.14184545 -0.06823105 [11] -0.20468966 -0.23815967 0.22113112 0.08977677 0.23567235
jj<-c(1,2,6,3,7,10,4,8,11,13,5,9,12,14,15) C<-B[jj]; C
[1] 0.52408090 0.47996616 0.54135982 0.11200672 -0.15985028 [6] -0.06823105 -0.17511026 -0.26277383 -0.20468966 0.22113112 [11] -0.09276455 -0.14184545 -0.23815967 0.08977677 0.23567235
______________________________________________ R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
David Winsemius Alameda, CA, USA
If you have a symmetric matrix, you can work with the upper triangle instead of the lower one, and you get what you want by simply using as.vector(A[upper.tri(A)]) Example:
a = matrix(rnorm(16), 4, 4) A = a + t(a) A
[,1] [,2] [,3] [,4] [1,] 0.3341294 0.5460334 -0.4388050 1.09415343 [2,] 0.5460334 0.1595501 0.3907721 0.24021833 [3,] -0.4388050 0.3907721 -0.4024922 -1.62140865 [4,] 1.0941534 0.2402183 -1.6214086 0.03987924
as.vector(A[upper.tri(A)])
[1] 0.5460334 -0.4388050 0.3907721 1.0941534 0.2402183 -1.6214086 No need to play with potentially error-prone index vectors; upper.tri does that for you. Hope this helps, Peter
On Fri, Jan 30, 2015 at 3:03 PM, Steven Yen <syen04 at gmail.com> wrote:
Dear I use sm2vec from package corpcor to puts the lower triagonal entries of a symmetric matrix (matrix A) into a vector. However, sm2vec goes downward (columnwise, vector B), but I would like it to go across (rowwise). So I define a vector to re-map the vector (vector C). This works. But is there a short-cut (simpler way)? Thank you.
A<-cor(e); A
[,1] [,2] [,3] [,4] [,5] [,6] [1,] 1.00000000 0.5240809 0.47996616 0.11200672 -0.1751103 -0.09276455 [2,] 0.52408090 1.0000000 0.54135982 -0.15985028 -0.2627738 -0.14184545 [3,] 0.47996616 0.5413598 1.00000000 -0.06823105 -0.2046897 -0.23815967 [4,] 0.11200672 -0.1598503 -0.06823105 1.00000000 0.2211311 0.08977677 [5,] -0.17511026 -0.2627738 -0.20468966 0.22113112 1.0000000 0.23567235 [6,] -0.09276455 -0.1418455 -0.23815967 0.08977677 0.2356724 1.00000000
B<-sm2vec(A); B
[1] 0.52408090 0.47996616 0.11200672 -0.17511026 -0.09276455 [6] 0.54135982 -0.15985028 -0.26277383 -0.14184545 -0.06823105 [11] -0.20468966 -0.23815967 0.22113112 0.08977677 0.23567235
jj<-c(1,2,6,3,7,10,4,8,11,13,5,9,12,14,15) C<-B[jj]; C
[1] 0.52408090 0.47996616 0.54135982 0.11200672 -0.15985028 [6] -0.06823105 -0.17511026 -0.26277383 -0.20468966 0.22113112 [11] -0.09276455 -0.14184545 -0.23815967 0.08977677 0.23567235
______________________________________________ R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
Great! Thanks. Thanks to all who tried to help.
as.vector(r[upper.tri(r)]) does it:
> e<-as.matrix(cbind(u1,u2,u3,v1,v2,v3))
> r<-cor(e); r
[,1] [,2] [,3] [,4] [,5] [,6]
[1,] 1.00000000 0.5240809 0.47996616 0.11200672 -0.1751103 -0.09276455
[2,] 0.52408090 1.0000000 0.54135982 -0.15985028 -0.2627738 -0.14184545
[3,] 0.47996616 0.5413598 1.00000000 -0.06823105 -0.2046897 -0.23815967
[4,] 0.11200672 -0.1598503 -0.06823105 1.00000000 0.2211311 0.08977677
[5,] -0.17511026 -0.2627738 -0.20468966 0.22113112 1.0000000 0.23567235
[6,] -0.09276455 -0.1418455 -0.23815967 0.08977677 0.2356724 1.00000000
> as.vector(r[upper.tri(r)])
[1] 0.52408090 0.47996616 0.54135982 0.11200672 -0.15985028 -0.06823105
[7] -0.17511026 -0.26277383 -0.20468966 0.22113112 -0.09276455 -0.14184545
[13] -0.23815967 0.08977677 0.23567235
At 06:56 PM 1/30/2015, Peter Langfelder wrote:
If you have a symmetric matrix, you can work with the upper triangle instead of the lower one, and you get what you want by simply using as.vector(A[upper.tri(A)]) Example:
a = matrix(rnorm(16), 4, 4) A = a + t(a) A
[,1] [,2] [,3] [,4] [1,] 0.3341294 0.5460334 -0.4388050 1.09415343 [2,] 0.5460334 0.1595501 0.3907721 0.24021833 [3,] -0.4388050 0.3907721 -0.4024922 -1.62140865 [4,] 1.0941534 0.2402183 -1.6214086 0.03987924
as.vector(A[upper.tri(A)])
[1] 0.5460334 -0.4388050 0.3907721 1.0941534 0.2402183 -1.6214086 No need to play with potentially error-prone index vectors; upper.tri does that for you. Hope this helps, Peter On Fri, Jan 30, 2015 at 3:03 PM, Steven Yen <syen04 at gmail.com> wrote:
Dear I use sm2vec from package corpcor to puts the lower triagonal entries of a symmetric matrix (matrix A) into a vector. However, sm2vec goes downward (columnwise, vector B), but I would like it to go across (rowwise). So I define a vector to re-map the vector (vector C). This works. But is there a short-cut (simpler way)? Thank you.
A<-cor(e); A
[,1] [,2] [,3] [,4] [,5] [,6] [1,] 1.00000000 0.5240809 0.47996616 0.11200672 -0.1751103 -0.09276455 [2,] 0.52408090 1.0000000 0.54135982 -0.15985028 -0.2627738 -0.14184545 [3,] 0.47996616 0.5413598 1.00000000 -0.06823105 -0.2046897 -0.23815967 [4,] 0.11200672 -0.1598503 -0.06823105 1.00000000 0.2211311 0.08977677 [5,] -0.17511026 -0.2627738 -0.20468966 0.22113112 1.0000000 0.23567235 [6,] -0.09276455 -0.1418455 -0.23815967 0.08977677 0.2356724 1.00000000
B<-sm2vec(A); B
[1] 0.52408090 0.47996616 0.11200672 -0.17511026 -0.09276455 [6] 0.54135982 -0.15985028 -0.26277383 -0.14184545 -0.06823105 [11] -0.20468966 -0.23815967 0.22113112 0.08977677 0.23567235
jj<-c(1,2,6,3,7,10,4,8,11,13,5,9,12,14,15) C<-B[jj]; C
[1] 0.52408090 0.47996616 0.54135982 0.11200672 -0.15985028 [6] -0.06823105 -0.17511026 -0.26277383 -0.20468966 0.22113112 [11] -0.09276455 -0.14184545 -0.23815967 0.08977677 0.23567235
______________________________________________ R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.