similar to: Efficent way to create an nxn upper triangular matrix of one's

Hi, suppose that we have a triangular upper matrix A test <- matrix(ncol = 4, nrow = 4) test[1, ] <- c(NA,1,1,1) test[2, ] <- c(NA,NA,1,1) test[3, ] <- c(NA,NA,NA,1) test[4, ] <- c(NA,NA,NA,NA) I know how quickly set diagonal value diag(test) <- 1. But how quickly set down value i.e. matrix is symmetrical? Is there in r project any quickly function? Thanks, Best Marcin

I would like to randomly shuffle a distance object, such as the one created by ade4{dist.binary} below. My first attempt, using sample(jc.dist) creates a shuffled vector, losing the lower triangular structure of the distance object. How can I Ishuffle the lower triangular part of a distance matrix without losing the structure? Thanks. --Dale x1 <- c(rep(0,4),1) x2 <- c(rep(0,2),rep(1,3))

Hi I have two symmetrical distance matrices and want to compute the correlation coefficient between them (after turning them into vectors). Is there a way of selecting only the upper triangular part of each matrix, then convert this into a vector so I can compute the correlation? Many Thanks Eleni Rapsomaniki

Hola! I have data in the form of a symmetric distance matrix, in the file I have recorded only the upper triangular part, with diagonal. The matrix is 21x21, and the file have row and col names, and some other information. I am trying to read with the following code (I tried many variations on it, but all give the same error). The items in the data file is delimited by white space. (Part

Hi, Is there any package that deals with triangular matrices? Say ways of inputting an upper (lower) triangular matrix? Or convert a vector of length 6 to an upper (lower) triangular matrix (by row/column)? Thanks! ----- ###################### PhD candidate in Statistics Big R Fan Big LEGO Fan Big sTaTs Fan ###################### -- View this message in context:

Hello! I'm trying to build a lower triangular matrix (with zeros in the diagonal) from a particular dataframe. The matrix I have to construct has 203 rows and 203 columns and that makes 20503 values to be included within (that's why I can't do it manually). To illustrate the dataframe I have, I'll give you an example of a dataframe and matrix with dimensions 6x6 (to make it

Hello, I want to create a triangular matrix and only keep the lower triangle entries without having to allocate memory for the whole matrix, is there any way I can do something like  A<-matrix(data, nrow=50)  but for a triangular matrix? Thanks ERV [[alternative HTML version deleted]]

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

Given a vector;> ab = seq(0.5,1, by=0.1)> ab[1] 0.5 0.6 0.7 0.8 0.9 1.0 The euclidean distance between the vector elements is given by the lower triangular matrix > dd1 = dist(ab,"euclidean")> dd1    1   2   3   4   52 0.1                3 0.2 0.1            4 0.3 0.2 0.1        5 0.4 0.3 0.2 0.1    6 0.5 0.4 0.3 0.2 0.1 Convert the lower triangular matrix to a full

Hi all, I am working on a filled contour plot which shows a triangular matrix data set (as shown below). Is there a possibilty to draw a triangular filled contour in a equilateral triangle (like a ternary plot)? Thanks in advance Johannes http://n4.nabble.com/file/n1557386/Bild3.png -- View this message in context: http://n4.nabble.com/Triangular-filled-contour-plot-tp1557386p1557386.html

Given a vector;> ab = seq(0.5,1, by=0.1)> ab[1] 0.5 0.6 0.7 0.8 0.9 1.0 The euclidean distance between the vector elements is given by the lower triangular matrix > dd1 = dist(ab,"euclidean")> dd1    1   2   3   4   52 0.1                3 0.2 0.1            4 0.3 0.2 0.1        5 0.4 0.3 0.2 0.1    6 0.5 0.4 0.3 0.2 0.1 Convert the lower triangular matrix to a full

How I make the below matrix | a^0 0 0 ... 0 | | a^1 a^0 0 ... 0 | | a^2 a^1 a^0 ... 0 | | . | | . | | . | | a^n a^(n-1) a^(n-2) ... a^0 | with no loops, where "a" is a constant? ======================================================================== C?zar de Freitas Depto. de Estat?stica - UFPE Recife - Pernambuco - Brasil

Hi, I would like to generate below triangular matrix for some a. 0 0 0 0 0 0 1 0 0 0 0 0 a 1 0 0 0 0 a^2 a 1 0 0 0 a^3 a^2 a 1 0 0 a^4 a^3 a^2 a 1 0 What's an efficient way to do this? (this matrix being KxK, K very large) Thanks Zava -------------------------------------------------------- This is not an offer (or solicitation of an offer) to buy/se...{{dropped}}

Hi, I''m trying to compile wxruby-1.9.2. This is my first time using rake. All I get is the following: (in /bld/lib/wxruby-1.9.2) rake aborted! can''t convert nil into String /bld/lib/wxruby-1.9.2/rakefile:48 (See full trace by running task with --trace) And with --trace: (in /bld/lib/wxruby-1.9.2) rake aborted! can''t convert nil into

Hello, I am trying to get fitted/estimated values using kernel regression and a triangular kernel. I have found packages that easily fit values from a kernel regression (e.g. ksmooth) but do not have a triangular distribution option, and density estimators that have triangular distribution options that I can't seem to use to produce estimated values (e.g. density). Any help is appreciated.

Hello, I have some xy data which clearly shows a non-monotonic, peaked triangular trend. You can get an idea of what it looks like with: x<-1:20 y<-c(2*x[1:10]+1,-2*x[11:20]+42) I've tried fitting a quadratic, but it just doesn't the data-structure with the break point adequately. Is there anyway to fit a triangular or 'tent' function to my data in R? Some sample code

Running the function below, tested using the cardiff dataset from splancs generates the following error. What changes do I need to make to get the function to work? Thanks. --Dale > gen.rpoints(events, poly, 99) > rpoints Error: object "rpoints" not found # test spatial data library(splancs) data(cardiff) attach(cardiff) str(cardiff) events <- as.points(x,y) ###

I've written the function below to simulate the mean 1st through nth nearest neighbor distances for a random spatial pattern using the functions nndist() and runifpoint() from spatsat. It works, but runs relatively slowly - would appreciate suggestions on how to speed up this function. Thanks. --Dale library(spatstat) sim.nth.mdist <- function(nth,nsim) { D <- matrix(ncol=nth,

Hi I''d like to put out a 1.9.3 release perhaps later this week/weekend. If you have a chance to test the build and samples esp with latest rubygems, please do. There are still some bugs on the list, and samples to do, but this should address all the build/install probs that have come up. And it would be good to get some testing and feedback on some of the new classes. A note on the

Hi, I am trying to create a triangular plot to show the 'composition' of a set of items with three variables (historically the percent sand, silt and clay in soil). So far I have tried the 'soil texture triangle plot' in the package plotrix and the 'ternary or triangular plots' in the package cwhtool (cwhmisc). Both have strengths and weaknesses, but neither has a