similar to: voronoi tessellations

There's Renka's STRIPACK, and TRIPACK, respectively, ACM TOMS Algorithms 772 and 751, and there's the R package "deldir" which does the Delaunay for a plane, but does anyone have or know of the tessellation in R for a sphere? Also, is there a standard indexing scheme for Delaunay facets, and perhaps of edges in such facets? I'd expect that to be a publication reference,

Hello everyone I have a problem with tripack package, I want to perform a Voronoi tessellation on a specific domain (I have the shape file), in order to weight my climatic data with the area ... How Can I do it? Thank you very much Andrea

Dear R-users, Does anyone know how to do weighted Voronoi diagrams (Dirichlet tesselation) in R? To be more specific, I have a set of coordinates for tree locations on a plot, and I'm looking for a way to do the tesselation so that the polygon size for each tree depends on the size of the subject tree, and the size of its neighbors. So, the location of the bisection between two trees

Hi all, I am running R 2.5.0 under Windows XP Media Center Edition. Here's a problem that's been stumping me for a few days now, and I can't find anything useful in the archives. I am using voronoi.mosaic (tripack package) to create proximity polygons for a study of vegetation competition and dynamics. The points lists are read in from a file for each plot, then 8 duplicates

I would like to create a voronoi map that can show me point values like the ones in colum street_cle. I was able to do it in tileplot(latticeExtra) like the ones attached, and with the following commands: xy=list(x=x2$X, y=x2$Y) xy$street_cle <- x2$street_cle tileplot(street_cle~ x*y, xy) But this is a trellis. Is it possible to be converted to a shapefile or image so I can plot it using

Hello list, I'm just getting started with using R - I have been trying over the past day or so to work out a method for generating voronoi polygons for PostGIS using SQL. I was able to put together a procedure which works relatively well, but is somewhat inefficient. Someone on the PostGIS list pointed me to the deldir() function in R, for which I can export a text file with x/y coordinates

Hi, I've been looking for functions that can do delaunay tesselation and generate voronoi cells. I came across deldir and tripack but both seem to be restricted to 2D points. Are there any packages that can do a tesselation in N dimensions? I know that Matlab and Mathematica use the qhull package to provide functions for this. Does anybody know of any R packages that do this (maybe by calling

Is there any pure r code to do delaunay or voronoi diagrams? Thanks! --------------------------------- [[alternative HTML version deleted]]

Hello. I'd like to convert voronois object created by tripack to polygons to use them in GIS(Geographic Information Systems) software. I tried to create voronoi objects by using following code. > library(tripack) > x <- rnorm(10) > y <- rnorm(10) > plot(x,y) > v<-voronoi.mosaic(x,y) > plot(v) But from here, I could not create polygons. Of course, I know

Hi all, Given a number of points (x,y) in a plane, I'd like to plot a map of polygons, so that 1) each polygon contains exactly one point 2) the polygon defines the area for which this specific point is closer than any other point. It's a bit like a map of areas "influenced" by that point, and it's obviously a matter of intersecting the perpendicular bisectors

Hello, trying to locate all the string commands in the base version of R, can't seem to find an area that describes them. I am in need to do some serious parsing of text data to create my dataset. Is there a summary link to all the character operators? string manipulations that would help in parsing text.

the R developer site has been down for some time, what gives? http://developer.r-project.org/

hi all members, please, i need you help... now a i´m working with veronoi polygons in a area with projections, but i need cut the polygons left. On other words, i need cut the polygons in the worked area. R help say that use the command voronoi.findrejectsites, but in this command i need put the numbers, any way...this command not cut!! do you can help me? Thank you for help me! José Bustos

Hello, we are needing to generate optimal (Fractional) designs for discrete choice applications, where we will be using logistic regression or multinomial logit as the modeling technique. It looks like optFederov, in the AlgDesign package may work, but not sure if this algorithm works when the variable of interest is binary or nominal? Anyone who are experts in this area, anyone interested

hello, i just got introduced to R - WOW its beautiful.. I am presently a SAS user and wanted to configure R to work in a multi-user enteprise environment. Client - Server. Where we have a strong LINUX server supporting about 10 statisticians with R. Anyone have any backround or information they can share to help me get jump-started on setting up R in this environment? Does each user have

Dear Help List, My name is Matt Oliver. I have been using R for about a year and find it very helpful. However, I have a need for a function that I cannot find. I am not very good at programming so I thought I would ask the group. I have an irregular grid of data (x = Longitude, y = Latitude). Each pair of my x,y has a categorical value. Obviously linear or any other numerically based

Hello, does R estimate belief networks to estimate chains of causality. Anyone point me to the right direction, or the most developed library? looking at DEAL>

There seems to be an error in the X11 display code: try: plot(c(-30000,-1,0,1,30000),c(30000,1,0,1,30000),type="l") points(c(-30000,-1,0,1,30000),c(30000,1,0,1,30000)) it gives a big "V" as expexted. Now zoom in using small xlim and ylim: plot(c(-30000,-1,0,1,30000),c(30000,1,0,1,30000),type="l", xlim=c(-5,5),ylim=c(0,5))

Hello, writing some R code to cleanse a data set, if the following set of symbols are identified then perform some actions. trying to write the minimum code to do this. tname = "VIX" checkticker = c("VIX", "TYX", "TNX", "IRX") if (tname == checkticker) { //perform some operations } result i get is > tname == checkticker

For "importance" it's probably best to stick with absolute values of coefficients, instead of value of the penalty parameter for which the coefficients changed to non-zero. Friedman skipped a lot of details on his rule ensemble in that talk, due to time constraint. In his implementation he was using his own algorithm, PathSeeker, for which paper and software are available on his