search for: triangul

Dear all; First of all, this is probably a more conceptual question than a R-related one, but still want to give it a try. When working with the interpolation function "interp" from the package akima and the triangulation function "tri.mesh" from package tripack I've got NA's for the interpolation and "error" for the triangulation. The data is arranged in a regular grid as opposed to what the help page for interp says but I think this is an interesting problem because I found this co...

This isn''t specific to RSpec, but is hopefully on-topic for this list. I like (especially when "ping pong pairing") to write a spec, then write the smallest amount of code I can to pass it (especially when "ping pong pairing"). Sometimes this means hard-coding a return value, which means another spec is needed to prove that the code is really behaving as it

Dear R-helpers, an rgl-ers in particular, what is the easiest way to plot a section of a plane in 3D, that is given by the xyz coordinates of the outline? Suppose I have a polygon - which I know for sure is a set of coordinates on the same plane. One method I found is to use surf.tri from the geometry package, and then plot the triangles with rgl.triangles. This method is not perfect though,

...tool. Worrying about it before those > are researched, etc is to use an English idiom: putting the cart > before the horse. I?m surprised that wireless access point controllers, by default, do not use the strength of the signal received from a device by three or more access points to simply triangulate the position of the device. Of course, you only get the positions of devices relative to access points, but once you have that, you only need to use a map of the place that shows all the access points and the positions of devices relative to them to figure out where everyone is. That?s a rathe...

Hi. I've tried to create a polygon with one hole by gpclib using following example script. holepoly <- read.polyfile(system.file("poly-ex/hole-poly.txt", package ="gpclib"), nohole = FALSE) area.poly(holepoly) plot(holepoly,poly.args=list(col="red",border="blue")) And I noticed plot function couldn't draw polygons with holes correctly.

Dear R helpers, I try to use the 'delaunayn' function in the 'geometry' package for Delaunay triangulation in 2 dimensions. For the four following points, I get a warning message : > coord=matrix(ncol=2,byrow=TRUE,c(622633,7073452, + 621228,7073517, + 621879,7071762, + 621065,7073331)) > lib...

Dear useRs, I'm trying to simply fill in the area under a curve using RGL. Here' the set up: x <- c(0.75,75.75,150.75,225.75,300.75,375.75,450.75,525.75,600.75,675.75, 0.5,50.5,100.5,150.5,200.5,250.5,300.5,350.5,400.5,450.5, 0.25,25.25,50.25,75.25,100.25,125.25,150.25,175.25,200.25,225.25) y <- c(0.05,4.91,9.78,14.64,19.51,24.38,29.24,34.11,38.97,43.84,

...of getting that Apparently Cisco can do it: https://www.cisco.com/c/en/us/products/collateral/wireless/wireless-location-appliance/product_data_sheet0900aecd80293728.html > sort of accuracy is to either have lots of pico cells so you know which > AP a device is connected to, or be able to triangulate. WiFi has a > reasonable range and devices like to hang on to an AP for as long as > possible, even if they can pass off on to a closer more powerful one. > > I know retailers are looking at targeting customers via their location, > but I think that currently needs the co-operati...

...f the data based on a no Kriging interpolation such as TIN based. I know the first thing I shold do is interpolate a full matrix for the region I have my points for, then contour should do its work. Any idea which function can be used for XYZ interpolations, maybe/hopefully based on a Delaunay triangulation in combination with linear or spline interpolation. Is there a package that allows me to do this? Kris -- ------------------------------------------------------------------------ http://perswww.kuleuven.ac.be/~u0027178/VCard/mycard.php?name=krisn http://gloveg.kuleuven.ac.be ------...

Hi, does anyone know if there is an implementation of qhull (http://www.qhull.org/) in R? anyone is planning on it? "Qhull computes convex hulls, Delaunay triangulations, halfspace intersections about a point, Voronoi diagrams, furthest-site Delaunay triangulations, and furthest-site Voronoi diagrams. It runs in 2-d, 3-d, 4-d, and higher dimensions. It implements the Quickhull algorithm for computing the convex hull. Qhull handles roundoff errors from flo...

...hat would show a surface of constant density which includes e.g. 50% of the points. Ideally, the surface would be semitransparent, such that I can show two or three at the same time. Alternatively, if I would calculate the contour surfaces myself, could I use R to semitransparently visualize a triangulated surface? Thank you very much for your help Lutz

I am trying to triangulate a point set as follows: > head(cbind(x,y)) x y [1,] -78.1444 -60.4424 [2,] -78.1444 -58.4424 [3,] -78.1444 -56.4424 [4,] -78.1444 -54.4424 [5,] -76.1444 -60.4424 [6,] -76.1444 -58.4424 > length(x) [1] 5000 > tri <- tri.mesh(x, y) Fehler in tri.mesh(x, y) : error in trmesh > tr...

...ng such surfaces? > > Yes, bang on. I knew of the > existence of the Delaunay code in the R libraries. Yes I want > to make a picture that places a planar facet on each triangle. > The resulting surface looks like the surface of a cut diamond > for example (assuming the cuts give triangular facets). So far > as I know there is no way to display such a 3D plot in R. persp > uses rectangular rather than triangular mesh. Once the trianglation was produced it would be just a minor change in the present "persp" function to plot it. The algorithm I use is to sort the fac...

Just been trying to get the polygon triangulation code from this package: http://www-2.cs.cmu.edu/~quake/triangle.html to dyn.load into R. Uh oh. Floating point exceptions. Track it down to some FPU diddling that the author deems is necessary. Here's my minimal code that breaks: flipme.c: #include <fpu_control.h> void flipme()...

Hi R helpers, Is there a function (package?) in R available which tests "spatial autocorrelation" between points (e.g. vector layer of weather stations)? (e.g. Moran's I...) Via the archives we found out that there is a package 'spdep' which uses grid data for testing spatial autocorrelation. Thanks a lot, Jan

...doing a search for "voronoi". > > The problem here is that `Voronoi tessellation' is a secondary name. The > concept has many names, including Dirichlet tessellation and Thiessen > polygons, and Dirichlet has priority over Voronoi. > > > Also, search for 'triangulation', since that is one of the uses of them. > > I know of packages deldir, tripack and perhaps geometry. > > > -Don > > > > At 11:46 PM -0400 7/18/06, zubin wrote: > > >Hello, looking to draw a voronoi tessellations in R - can anyone > > >recomm...

Hello List, I'm a very new user to the R system. I'm only beginning to learn the basics, but so far I've been able to do little more than try a few examples, and of course begin reading the documentation. My primary motivation for exploring R is the availability of tools like the 'spdep' package for calculating spatial statistics such as Geary's C and Moran's

Here are a couple things I would try to help triangulate on the problem. Try a vanilla upstream compiler for an in-tree target. (IIRC you have your own target.) If that fails, it's pretty optimal for you because you should be able to reduce a test case and file a PR. If it doesn't fail, that suggests it's either something your target do...

...>> are researched, etc is to use an English idiom: putting the cart >> before the horse. > > > I?m surprised that wireless access point controllers, by default, do not > use the strength of the signal received from a device by three or more > access > points to simply triangulate the position of the device. Of course, you > only get the positions of devices relative to access points, but once you > have that, you only need to use a map of the place that shows all the access > points and the positions of devices relative to them to figure out where > everyone...

Since updating to the LLVM v5.0 Final tag, I am seeing a crash when I enable '-g'. With a Debug build this hits an assertion at line #923 in 'lib/CodeGen/AsmPrinter/DwarfDebug.cpp': assert(EndLabel && "Forgot label after instruction ending a range!"); The values of related variables at this time are: 'Begin' is: DBG_VALUE %I23, %noreg,