Questions tagged [convex-hull]

Smallest bounding area for an object or group of objects with no concave angles.

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Creating convex hull by expression by aggregating points

I would like to recieve the centroid of a convex hull of a group of points in a layer, grouped by its name. This needs to be done by expressions, available in QGIS 3.4. E.g. I have this list of points:...
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Adapting a ConvexHull fonction to a ConcaveHull one

I have a database with over 150 000 points in a EPSG 2950 projection. As I wanted to cluster those points in polygons, I used a ConvexHull fonction. The goal was to create clusters where I would find ...
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Using convex hull for interpolation of individual plots or lump plots together in ArcMap?

This question is inspired by Using kriging to extrapolate values outside of sampling polygon in ArcMap? I'm working on a project trying to understand the lasting effects of historic scientific ...
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How to create view from ST_ConvexHull

I have a simple SpatiaLite DB containing one table with point features. I would like to generate a Minimum Convex Hull around that features. I could do that easily with one of the Convex Hull tools ...
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Inflating the boundaries created with convex hull

I have a set of lan and lat points and have plotterd a convex hull for them using QGIS. A polygon is created along the set of points and plotting them on the MAP. Now I am trying to inflate the size ...
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Detecting turns of route?

I'm doing a Python simulation of a vehicle, driving along a specified path. I generate dummy GPS readings, that fetch the current position of the vehicle, with some randomized error added. After a ...
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Convex Hull issue in QGIS 1.8

When creating convex hulls based on input field in qgis 1.8, there seems to be always one less convex hull created for the unique values in the input field. For example; I have a point vector file, ...
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How can I use Convex Hull to select an area with a space from the points?

This refer to this post : Read Here My goal is to select an area covering some points, but maintaining some space from points of border, like in the follow picture : I think ST_Convexhull will do ...
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Convex Hull not outputting expected number of features

I have a .csv file with observations of various species and I want a polygon to illustrate the area where those species occur. I ran the Convex Hull, grouped by the species' names field, which ...
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GRASS v.hull for many point sets

I have map "my_pointmap" with 3D points with ids=(1,2,3...N). I have also list of subsets of these point ids , S = [(1,2,3,4),(2,4,10,12), ...]. I would love to get GRASS GIS vector map with |S| 3D ...
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Creating Polygon from groups of points

I have a point feature class (Address Points) and I am interested in creating a polygon feature class around groups of 500 address points. Is there a way I can do this programmatically, as opposed to ...
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Looking for a US state file for geofences with as few geofences per state as possible (so group islands with mainland)

UPDATED TO MUCH MORE DETAILED QUESTION I'm building a set of geofences to be installed on a GPS unit to track vehicles as they cross state lines. The list of geofences are simple latitude/longitude ...