similar to: 'subscript out of bounds' in matrices

I'd like to generate many matrices (let's say 100 matrices of 4x4), of which diagonal elements are being drawn from each set of sample of known distribution. What would be the best way? I've been trying to find any previous threads for this topic, but haven't been able to find one. Thanks. Kevin [[alternative HTML version deleted]]

Here's an easy question: I'd like to convert a symmetric matrix to a vector composed of the upper.tri() part of it plus the diagonal, and convert it back again. What's the best way to achieve this? I'm wondering if there are some built in functions to do this easily. I can encode fine: v <- c(diag(A),A[upper.tri(A)]) but I don't see an easy way to recover A from v

Dear List, is there an elegant (or even not elegant) way how to transform dissimilarity or distance matrix A (or, in general, arbitrary symmetrical matrix) by transposition of rows and columns into a form closest to "block diagonal" matrix B? The matrix A is adjusted the following way A[A<epsilon] <-0 #(epsilon is given "small" number) B: (in its ideal form)

Dear List: I am working to construct a matrix of a particular form. For the most part, developing the matrix is simple and is built as follows: vl.mat<-matrix(c(0,0,0,0,0,64,0,0,0,0,64,0,0,0,0,64),nc=4) Now to expand this matrix to be block-diagonal, I do the following: sample.size <- 100 # number of individual students I<- diag(sample.size) bd.mat<-kronecker(I,vl.mat) This

List members, Via searches I've seen similar discussion of this topic but have not seen resolution of the particular issue I am experiencing. If my search on this topic failed, I apologize for the redundancy. I am attempting to generate random covariance matrices but would like the corresponding correlations to be uniformly distributed between -1 and 1. The approach I have been using is:

I have output from a program which produces a distance matrix I want to read into a clustering program in R. The output is a .txt file and is 'almost' lower triangular in the sense that it is just the triangle below the diagonal. So for example a 4-by-4 distance matrix appears as, 1 2 3 4 5 6 i.e. it looks like a lower triangular of a 3-by3. I thought I might be able

Hello there, I'm trying to plot vectors with p<0.1 in a NMDS ordination plot using p.max. Below the scripts I'm using. I guess I'm missing something! could you please give me a hand? species<-metaMDS(species_matrix)ef<-envfit(species,environmentaldata_file,permu=999,na.rm=TRUE)efplot(species, dis="sites")plot(ef,p.max=0.1) Error in plot.envfit(ef, p.max = 0.1) :

I have generated the following: x= E1 E2 E3 D1 0 0 1 D2 1 0 3 D3 0 2 0 y= E1 E2 E3 D1 0 0 1.75 D2 1.75 0 1.3125 D3 0 3.5 0 Where x and y are linked by: y =sum(x) * x / (rowSums(x)%o%colSums(x)) N=x[x[1:3,]>0] R=y[y[1:3,]>0] Now suppose I ONLY

I don't know the details of pls (in the pls.pcr package, I assume), but if you use validation="CV", that says you want to use CV to select the best number of components. Then why would you specify ncomp as well? Andy > From: ryszard.czerminski at pharma.novartis.com > > When I try to use ncomp parameter in pls procedure I get > following error: > > >

Hi I want to write a little function that takes a vector of arbitrary length "n" and returns a matrix of size n+1 by n+1. I can't easily describe it, but the following function that works for n=3 should convey what I'm trying to do: f <- function(x){ matrix(c( 1 , 0 , 0 , 0, x[1] , 1 , 0 , 0, x[1]*x[2] , x[2] , 1 , 0,

Greetings, I have a seemingly simple task which I have not been able to solve today. I want to construct a symmetric matrix of arbtriray size w/o using loops. The following I thought would do it: p <- 6 Rmat <- diag(p) dat.cor <- rnorm(p*(p-1)/2) Rmat[outer(1:p, 1:p, "<")] <- Rmat[outer(1:p, 1:p, ">")] <- dat.cor However, the problem is that the matrix

Dear useRs, Trying to replace the diagonal of a matrix is not working for me. I want a matrix with .6 on the diag and .4 elsewhere. The following code looks like it should work--when I lookk at mps and idx they look how I want them too--but it only replaces the first element, not each element on the diagonal. mps <- matrix(rep(.4, 3*3), nrow=n, byrow=TRUE) idx <- diag(3) mps idx mps[idx]

I need to find solutions to a tridiagonal system. By this I mean a set of linear equations Ax = d where A is a square matrix containing elements A[i,i-1], A[i,i] and A[i,i+1] for i in 1:nrow, and zero elsewhere. R is probably not the ideal way to do this, but this is part of a larger problem that requires R. In my application it is much easier (and much faster) to generate the diagonal and

Dear sirs, 1...........Kindly tell me is it possible to form a matrix which contains a no of matrices.. for eg.. if a,b,c,d are matrices.... and e is a matrix which contains a,b,c,d as rows and columns.. 2..........Is it possible to form array of array of arrays for eg.. "A" contains two set of arrays (1,2)...and each A[1] and A[2] individually contains two set of arrays I tried like

Dear R-users, I would like to know whether there is a way to extract a diagonal of an inverse matrix without computing the inverse of the matrix itself. The size of my matrices are really huge and, also using sparse matrix, computing the inverse leads to storage problems and low speed. In other words, given a square matrix A, I aim to know diag(B), where B=solve(A), without computing solve(A).

Hi All, I am trying to replace the "NA" values in a matrix by using the following function: it gets a "name" of the matrix or list or vector and turns it to a matrix called "m". then checks the elements of the matrix and if any of them is "NA" replace them with "0". rep=function(name){ m=as.matrix(name) for(i in 1:length(m)){ for(j in

Hello and sorry that I still haven?t found a solution for my problem. I need to extract the lower and upper triangle from a square matrix including the diagonal. This diagonal is not zero in that special case. I tried with as.dist w<-as.dist(w, diag = TRUE) > w 1 2 3 4 5 1 0 2 2 0 3 3 8 0 4 4 9 14 0 5 5 10 15 20 0 but found no way to keep the diagonal that is in the

Hi, I have this sample data below and would like to create a list of matricies. setseed(1254) id <- c(1,1,1,1 ,2,2,2) o <- as.factor(c(1:4, 1, 3, 4)) r <- rep(.5, 7) v <- rnorm(7) s <- rnorm(7) dat <-data.frame(id, o, r, v, s) dat #> dat # id o r v s # 1 1 0.5 0.7024631 2.0813672 # 1 2 0.5 -0.5541955 0.1095156 # 1 3 0.5 -1.0418167 0.4164930 # 1

Your message doesn't help us very much. You haven't said what kind of calculation it is you want to do, and that certainly matters. For example, for some kinds of computations the solution you started below would work fine: > M <- matrix(1:16, 4, 4) > is.na(diag(M)) <- TRUE > M [,1] [,2] [,3] [,4] [1,] NA 5 9 13 [2,] 2 NA 10 14 [3,] 3 7 NA

It concerns trival diagonal matrices: > diag(1) [,1] [1,] 1 > diag(rnorm(1)) <0 x 0 matrix> > diag(rnorm(1),nrow=1) [,1] [1,] 0.4843697 There's an obvious work around... but I thought it was worth notifying the list. Regards, John Marsland ********************************************************************** This is a commercial communication from