similar to: Is it R or I?

Dear R-list members, Just wondering if there is any way to compute the duplication matrix in R. I tried to search for it but only found functions "xpnd" and "vech". Basically for a symmetric n by n matrix A, the duplication matrix D_n is a matrix of dimension n^2 by n(n+1)/2 such that D_n vech(A)= c(A), where c(A) just vectorizes A. The duplication matrix is defined on page

Full_Name: Anantha Prasad Version: 1.1.1 OS: Linux Submission from: (NULL) (199.131.134.30) I am trying to convert some S-PLUS code to R (a tcl/tk application that uses R)... here is the error I got in R (but not in S-PLUS)...so I am wondering if it is a bug. Eg., the foll. extract from a function runs fine in S-PLUS but gives the error: Error in x[[j]] : subscript out of bounds in R code

Hi all, I have a problem with libvirt, it works slow. For example, "virsh list" takes 6..7 seconds. I found this in libvirt log: ... 11:38:12.765: debug : virEventDispatchHandles:477 : Dispatch n=8 f=56 w=9 e=1 0x25ce830 11:38:12.765: debug : virEventUpdateHandleImpl:147 : Update handle w=8 e=3 11:38:12.765: debug : virEventInterruptLocked:668 : Interrupting 11:38:12.766: debug :

Let say i have a square matrix and applied the 'vech' operator to stack the lower triangular elements into a vector: > Mat <- matrix(1:25, 5) > Mat ? ? ?[,1] [,2] [,3] [,4] [,5] [1,] ? ?1 ? ?6 ? 11 ? 16 ? 21 [2,] ? ?2 ? ?7 ? 12 ? 17 ? 22 [3,] ? ?3 ? ?8 ? 13 ? 18 ? 23 [4,] ? ?4 ? ?9 ? 14 ? 19 ? 24 [5,] ? ?5 ? 10 ? 15 ? 20 ? 25 > Mat[lower.tri(Mat)] ?[1] ?2 ?3 ?4 ?5 ?8 ?9 10 14

# I've tried to make this easy to paste into R, though it's probably so simple you won't need to. # I have some data (there are many more variables, but this is a reasonable approximation of it) # here's a fabricated data frame that is similar in form to mine: my.df <- data.frame(replicate(10, round(rnorm(100, mean=3.5, sd=1)))) var.list <- c("dv1",

Hello I have data like this x1 x2 x3 x4 x5 I want to create a matrix similar to a correlation matrix, but with the difference between the two values, like this x1 x2 x3 x4 x5 x1 x2-x1 x3-x1 x4-x1 x5-x1 x2 x3-x2 x4-x2 x5-x2 x3 x4-x3 x5-x3 x4 x5-x4 x5 Then I