qhull

Processing cannot find library

由 江枫思渺然 提交于 2019-12-13 17:29:19
问题 I've tried importing from a jar file (quickhull3d for example) in Processing 2.2.1 and 3.2.1 on Linux and Mac based on the instructions given here My directory structure looks like this ../Processing/Sketchbook/libraries/quickhull3d/library/quickhull3d.jar The Processing IDE preferences set the sketchbook location to ../Processing/Sketchbook In my .pde file, I have the opening line import quickhull3d.*; and I get the error: No library found for quickhull3d Libraries must be installed in a

How to remove skinny triangles in scipy.spatial.Delaunay()

由 家住魔仙堡 提交于 2019-12-13 04:45:38
问题 I have a scipy.spatial.Delaunay() triangulation, and I would like to remove 'skinny' triangles from it. How would I do this? I have seen that some other software (like here: Houdini triangulate2d) have a 'minimum angle' option precisely to prevent skinny triangles. Is there some equivalent option for scipy.spatial.Delaunay() , or can someone provide a simple algorithm? 来源： https://stackoverflow.com/questions/56136510/how-to-remove-skinny-triangles-in-scipy-spatial-delaunay

Qhull Convex hull wants me to input at least 3 points

由 北慕城南 提交于 2019-12-11 06:09:19
问题 Update: I've decided to try to use a linear programming package in order to determine if the vertices of the two polytopes are linearly separable. (The vertices are really my data, not the polytopes.) I think this will work better, so I no longer need an answer to this question. I'm writing some code that involves checking if certain polytopes are disjoint. These polytopes are defined by the convex hulls of their vertices, and I'm creating the convex hulls using Qhull . In particular, I'm

qhull Library - C++ Interface

由 感情迁移 提交于 2019-12-09 04:19:41
问题 The qhull library ( qhull.org) has several examples to start in his website, but all the information regarding to the C++ is not very useful to me. I am trying to make a simple convex Hull of 3D points that I read from a file, I can´t use the technique that is suggested in the website of calling the qhull.exe as an external application because I need to make several convex hull from some modifications that I made in the data points. I can´t find a simple example for doing this, can someone

Plot convex hull given by quickhull algorithm in R (convhulln function)

由 纵然是瞬间 提交于 2019-12-06 14:48:01
问题 I need to plot the convex hull given by quickhull algorithm in R. Here is an example. library(geometry) x1 <- rnorm(100, 0.8, 0.3) y1 <- rnorm(100, 0.8, 0.3) ConVexHull<-convhulln(cbind(x1,y1),"FA") ConVexHull$hull gives a m-by-dimension index matrix of which each row defines a dim-dimensional “triangle”. I know how to plot using chull function but I am not sure if chull gives the same hull as given by convhulln Plot_ConvexHull<-function(xcoord, ycoord, lcolor){ hpts <- chull(x = xcoord, y =

Picture Convex hull in 3D Scatter Plot

由 心已入冬 提交于 2019-12-06 14:09:39
问题 I followed the tutorial about 3D visualization using the package "rgl" here So I was able to draw a 3D Scatter Plot with "iris" data and create an ellipsoid surrounding 95 % of the data points: library("rgl") data(iris) x <- sep.l <- iris$Sepal.Length y <- pet.l <- iris$Petal.Length z <- sep.w <- iris$Sepal.Width plot3d(x, y, z, col="blue", box = FALSE, type ="s", radius = 0.15) ellips <- ellipse3d(cov(cbind(x,y,z)), centre=c(mean(x), mean(y), mean(z)), level = 0.95) plot3d(ellips, col =

Make qhull/qvoronoi limit Voronoi to convex hull or given polygon

由 对着背影说爱祢 提交于 2019-12-06 06:47:05
问题 A planar Voronoi tesselation will always have unbounded polygons (infinite regions). How do I tell qhull/qvoronoi to intersect the tesselation with either the original points' convex hull, or with a polygon I explicitly specify (probably a rectangle). Specific example ( https://github.com/barrycarter/bcapps/blob/master/bc-temperature-voronoi.pl ): I map latitudes/longitudes (inaccurately) to the 2-D rectangle (-180,180)*(-90,90), and apply qvoronoi to the result. I can't handle unbounded

Calculating a Voronoi diagram for planes in 3D

由 放肆的年华 提交于 2019-12-06 02:26:12
Is there a code/library that can calculate a Voronoi diagram for planes (parallelograms) in 3D? I checked Qhull and it seems it can only work with points, in its examples Voro++ works with different size of spheres but I couldn't find anything for polygons. In this image (sample planes in 3d) the parallelograms are 3D since they have a thickness, but in this case the thickness will be zero.! Voronoi cells are not parallelograms. You are confused here by the image you posted. Voronoi cell borders are parts of the hyperplanes that are separating the individual means. Check out this website

how to plot non-convex surface from set of n x 3 data

由 拜拜、爱过 提交于 2019-12-05 19:17:55
Is there a straight forward way to plot a non-convex surface in R? I have used something like the following for convex surfaces and it works fine: xyz <- cbind(y,x,z) tbr <- t(surf.tri(xyz, delaunayn(xyz))) rgl.triangles(xyz[tbr,1], xyz[tbr,2], xyz[tbr,3]) However, for non-convex surfaces, concave areas become filled. I think this is a problem with the function delaunayn() as it uses the Qhull library which does not support constrained Delaunay triangulations or mesh generation of non-convex objects. Any suggestions appreciated. P.S. I have data as an ascii file but it has 3 columns and is 225

Plot convex hull given by quickhull algorithm in R (convhulln function)

由 馋奶兔 提交于 2019-12-04 19:09:32
I need to plot the convex hull given by quickhull algorithm in R. Here is an example. library(geometry) x1 <- rnorm(100, 0.8, 0.3) y1 <- rnorm(100, 0.8, 0.3) ConVexHull<-convhulln(cbind(x1,y1),"FA") ConVexHull$hull gives a m-by-dimension index matrix of which each row defines a dim-dimensional “triangle”. I know how to plot using chull function but I am not sure if chull gives the same hull as given by convhulln Plot_ConvexHull<-function(xcoord, ycoord, lcolor){ hpts <- chull(x = xcoord, y = ycoord) hpts <- c(hpts, hpts[1]) lines(xcoord[hpts], ycoord[hpts], col = lcolor) } xrange <- range(c(x1
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