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Questions tagged [convex-hull]

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.

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Python convex hull with scipy.spatial.Delaunay, how to eleminate points inside the hull?

I have a list of 3D points in a np.array called pointsList, values are float : [[1., 2., 10.], [2., 0., 1.], [3., 6., 9.], [1., 1., 1.], [2., 2., 2.], [10., 0., 10.], [0., 10., 5.], ... etc. This code makes a Delaunay triangulation of the…
adrienlucca.net
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get the index of point which create ConvexHull

I amtrying to use scipy.spatial (from scipy.spatial import ConvexHull)to draw convex hull of series of points. import pylab as pl from scipy.spatial import ConvexHull pl.figure() pl.hold(True) points = np.concatenate((x, y), axis=1) hull =…
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D3 drawing a hull around group of circles

I want to draw a hull around a grouped force directed graph build with d3. I have build the graph with the circles. But I now want to join the intersections of the circles with a path(hull). If not joining the intersections, Drawing a hull…
Sunil Raj
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android java opencv 2.4 convexhull convexdefect

Open-CV 2.4 Android-Java: i have searched for contours (list of MatofPoint) like this: Imgproc.findContours(roi_mat, contours, hierarchy, cfg.retMode, cfg.apxMode); and then the convexhull (has to be a list of MatofInt ) for (int k=0; k <…
ddd
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Is there a way to dynamically draw lines between points over a coordinate plane?

I am completing a project in which I have implemented a brute force algorithm for solving the Convex Hull problem. I need to also create a visual for this algorithm. I am trying to create a coordinate plane ranging from (-100, 100) on both the x and…
VaniCodes
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Calculating and displaying a ConvexHull

I'm trying to calculate and show a convex hull for some random points in python. This is my current code: import numpy as np import random import matplotlib.pyplot as plt import cv2 points = np.random.rand(25,2) hull =…
Atakan ADA
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Extract Characters using convex Hull coordinates - opencv - python

I have character images like this: Using following code I could get contours and convex hull, then I could draw convex for each character. import cv2 img = cv2.imread('test.png', -1) ret, threshed_img = cv2.threshold(cv2.cvtColor(img,…
Ishara Madhawa
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Test case data for convex-hull

I need to make a 2D convex hull function for a class assignment and I want a more robust test cases than the assignment provides. Does anyone known of a largish test cases (25 < n < 100) with the solution?
BCS
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How to check for convexity of a 3d mesh?

Is there a fast way to do this? Searching online shows convexity of functions or single polygons. But I need the ability to check this for the whole model. An object can have convex faces but can be concave as a whole like a torus.
Joan Venge
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Convex hull routines in scipy.spatial gives me back my original set of points

I have a set of points and want to find the convex hull. When I give them to scipy.spatial (either ConvexHull or Delaunay), I just get the original set of points back. By construction, this should not be the case. Here are the points as a pickled…
benten
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Convex Hull and SciPy

I'm trying to use scipy (0.10.1) for a quick hack to visualize the convex hull. I can get the convex hull using the following code: vecs = [[-0.094218, 51.478927], [-0.09348, 51.479364], [-0.094218, 51.478927], ... [-0.094218,…
Has QUIT--Anony-Mousse
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Min area enclosing rectangle from set of n points

I want to find minimal enclosing rectangle for set of n points. First I found convex hull. If I have a convex hull from set of points ( I got it by doing Graham scan) stored as a sorted list. And from every edge of that convex hull, by binary search…
user940009
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ConvexHull in Graphics - Mathematica

Trying to plot a ConvexHull Using PlanarGraphPlot from the ComputationalGeometry package, it does not work when used in graphics. Any Idea on how to plot the ConvexHull using Graphics ?
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Sorting by Polar Angle

I'm trying to implement the Graham’s Scan algorithm for a convex hull in Java, and have trouble sorting the points by polar angle with respect to the point with lowest y-value. I have found this answer and understand how to calculate the polar…
Pakchoiandbacon
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Best Algorithm to find the edges (polygon) of vertices

I have a large array of vertices, some of them are edges, some are redundant (inside the shape) and I want to remove those. The simplest algorithm I could think of is checking one by one if they hit the shape formed by the others. But it should be a…
fabiopedrosa
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