Convex-hull of a set of points X in a Euclidean space is the convex set with smallest area that contains all points of X.
Questions tagged [convex-hull]
538 questions
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R retain order from a vector, apply it to another vector
This is related to a previous question:
Basic R, how to populate a vector with results from a function
But I thought I would post a new one because I have an additional requirement. Take this R code.
X <- matrix(stats::rnorm(100), ncol = 2)
hpts <-…
KrisErickson
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Basic R, how to populate a vector with results from a function
So I have a list of coordinates that I perform a chull on.
X <- matrix(stats::rnorm(100), ncol = 2)
hpts <- chull(X)
chull would return something like "[1] 1 3 44 16 43 9 31 41". I want to then multiple X by another vector to return only the…
KrisErickson
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Converting convexHull Points Into Points I Can Use
I'm using Visual C++ 2010 Express with OpenCV, and I'm trying to track two hands. So far I already have the convexHull and convexityDefects, but I'm having trouble getting the points of the convexHull. I'd like to use them to draw a line from the…
Newbie97
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how to apply convex hull algorithm in MATLAB on gray scale image
I want to apply convex Hull in MATLAB on gray scale image but regionprop and other built-in functions that are provided on net are not working please help me, to find objects from images that have less connectivity between pixels.
Filza Malik
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Intersection of two convex set in n-dimensional space
Let $X={x_1,\ldots,x_p}$ and $Y={y_1,\ldot,y_q}$ be two set of points in $\mathbb{R}^n$.
Is there a method to find $\mathrm{conv}(X)\cap \mathrm{conv}(Y)$ as $\mathrm{conv}(Z)$, where $Z$ is some subset of $\mathbb{R}^n$?
SAM
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Convex Hull calculation in Point Cloud Library fails in 2 as well as 3 dimensions
i'm following the tutorial of the PCL docs for calculating a 2D Convex Hull see here.
I have a cloud and some indices, project them on a plane with given coefficients and then calculate the convex hull. Here's the code:
PointCloud::Ptr…
moatilliatta
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what do I get from scipy.spatial.Delaunay.convex_hull
I thought scipy.spatial.Delaunay.convex_hull is returning an array where every point/index is used twice, because one point belongs to two edges. But in my case there are several indices only one time:
hull = [[5053 6943]
[6219 5797]
…
Munchkin
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Algorithm for selecting outer points on a graph ("rich" convex hull)
I'm looking for an efficient way of selecting a relatively large portion of points (2D Euclidian graph) that are the furthest away from the center. This resembles the convex hull, but would include (many) more points. Further criteria:
The number…
Gaminic
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extract nonconvex hull from result of minkowski sum using boost
http://postimg.org/image/sgl1q3vf5/
http://postimg.org/image/787d8ogy9/
As the pics shown above, I tried to calculate the minkowski sum of a polyline and a circle and the resulting shape covers the area of the polygon Im trying to generate. I use…
david lin
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Extrude convex hull
Hy!
I have a set of points in 3d which all lie on a plane and represent the floor of a room.
Now I want to create walls. My idea is to extrude the floor, or to use translational sweeps.
I tried to finds some code in the web or information where to…
user2576458
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Initiating Jarvis' March (gift-wrapping) for convex hulls
I am trying to implement the giftwrapping algorithm on a set of points to find their convex hull.
It says that the next point in the convex hull is the leftmost point (this is from wikipedia) from the point of view of the last point found. However,…
James
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Print vector of coordinates obtained from a text file in a specific format in C++
The following is the code that I am working on -
#include
#include
#include
#include
#include
using namespace std;
struct coord {
long x,y;
};
int main()
{
ifstream nos("numbers.txt");
vector<…
sj22
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Prove that the farthest point among a set of points(in 2-d plane) should lie on the convex hull
The question speaks for itself. It is required to prove that given a set of 2-d points, the pair of points farthest from each other must lie on the convex hull.
sudeepdino008
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splitting and merging of kinetic convex hulls in c++
note:I am not sure if this questions belongs here, if appropriate please move to appropriate stackexchange site.
I am developing a multiplayer game.
What I want to maintain in my code : 2d clusters.
What are clusters: they are aggregation of users…
user494461
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1 answer
want the outline of coordinates, perhaps not the convex hull
I wanted a direct outline of given points on a map. I did find a divide-and-conquer algorithm, but its results are too abstract. I put in the coordinates of Texas and the convex hull of Texas looks nothing like the state.
I later realized I'm not…
Emwat
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