Questions tagged [voronoi-thiessen]

Thiessen polygons are polygons (generated from a set of points) whose boundaries define the area that is closest to each point relative to all other points. Thiessen polygons are mathematically defined by the perpendicular bisectors of the lines between all points and are created by means of a triangulated irregular network (TIN) structure.

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Creating Thiessen polygons using ArcMap

When creating the Thiessen polygon for a X,Y co-ordinates. It is showing like this. When I set the extent manually I'm not getting the polygon properly.
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Weighted Voronoi polygons in QGIS

I want to build weighted Voronoi polygons in QGIS, as in How to draw weighted voronoi polygons (thiessen) from points in QGIS?? but the aforementioned answer and code (https://github.com/HichamZouarhi/...
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Weighted Voronoi polygons in R

I want to build weighted Voronoi diagram in R, as in How to draw weighted voronoi polygons (thiessen) from points in QGIS? or Create weighted Thiessen polygons?, but I could not find any function for ...
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QGIS Voronoi polygons being generated incorrectly

I am trying to generate some Voronoi/Theissen polygons from points across the UK. From my understanding, any point within a Voronoi polygon should be closer to that polygons origin point than any ...
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Calculating the distance between the furthest vertex of a Voronoi polygon and the point from which it was generated

I need to calculate the distance between the furthest vertex of a Voronoi polygon and the point that generated it. I need to calculate this distance for all Voronoi polygons. Is there a way to do it ...
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I want to create a Voronoi diagram while retaining the data in the data frame

We will use st_voronoi() to create a Voronoi diagram. I have three questions. Point one. I understand that the argument to st_voronoi() should be the following data. ■SFC format (an error occurs ...
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R - Voronoi polygons from lines

I use R (and sf, mainly) and I was wondering if it's possible to create Voronoi polygons starting from LINESTRING objects instead of POINT. For example, given a sfc such as # package library(sf) #&...
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Voronoi polygons for a layer with point objects, attributes are lost for points with different attributes but same coordinates

I use QGIS v3.4. I have a layer with points where some points has exactly the same coordinates but different attribute fields. When I generate voronoi polygons for this layer the attributes of the ...
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Using Voronoi.Skeleton in QGIS [duplicate]

My purpose is to make a central line from a polygon. For this I use the skeleton algorithm from a polygon, but I did not manage to get a line. I draw the polygon. I launch the program. It doesn't ...
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Create Voronoi with ArcMap

I'm trying to create voronoi map out of a layer pf points in ArcMap (after very long time ot using ArcMap) ,using the geostatistical analyst, but for some reason I get unexpected results: I click ...
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Making polygon for every point in set using voronois?

I'm trying to make polygons from points, were each point will be represented by one polygon. I tried using voronois, but the results are incomplete. While I more or less understand where this ...
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QGIS Voronoi polygons wrong behaviour

I am trying to use Voronoi polygons algorithm in QGIS in a dataset of points but strangely I am getting an overlap of polygons. These points correspond to the vertices of a set of polygons. When ...
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Combining cost analysis and voronoi-like area interpolation regarding slopes

I have DEM raster data of an island and I have 10 points (cities). My task is to map the island into areas. Inside these areas everything must be nearest to the corresponding city/point, and each ...
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466 views

Insert n points equally distributed into many polygons

I know the "Random Points inside Polygons" tool in QGIS. It generates the below output. What I want to achieve however are 8 equally distributed points for each of the polygons. I thought of dividing ...
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1answer
147 views

Creating Voronoi diagrams using JTS and the manhattan or minkowski distance metrics

In Java I am using the JTS library. Is it possible to use this library to generate Voronoi sites using different types of distance functions? https://locationtech.github.io/jts/javadoc/org/...
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1answer
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Find the side of a polygon pointed by an azimuth

I have a dataset of points (longitude, latitude) and I used QGIS get a Voronoi diagram of these points. Each point has an azimuth and a wedge width that I also managed to visualize in QGIS. As you ...
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GRASS GIS: Computing center line of raster feature representing a river

My goal: Convert a raster layer representing a river feature (see picture) to the center line of the river stored as a polyline feature. Limitation: The whole process has to be automated. I can ...
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Voronoi Diagram on a given polygon using QGIS

I am trying to create a Voronoi Diagram on a specific polygon, but there is some issue when dealing with edges. Here is how I do it: Preparing the points for Voronoi and the polygon for the diagram ...
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Creating polyline between points using ArcGIS Desktop?

Using ArcGIS Desktop, I am trying to create a frontline of a battle from WW2. I have known points, and want a polyline to run between both sides. There is 87 days of combat, so every day there is a ...
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average weighted value by region with use of Voronoi in Qgis

I have a vector layer of Voronoi polygons. This layer has three columns -longitude, latitude, Z-value. I need to cut polygons by mask of administrative area and then I need to calculate average-...
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1answer
265 views

Create a line string from street geometry

I'm currently facing some hard times trying to create a simplified line from a street geometry. The data that I'm currently using comes from OpenStreetMap, using osm2pgsql.(Which means PostGIS, but I'...
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Voronoi polygons tool not working in QGIS

So I've been trying to build up some Voronoi diagram out of my point dataset but I can't seem to get it to work. When I try it on QGIS 3.4 I get the following error: Traceback (most recent call ...
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4answers
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QGIS 'Voronoi polygons' freezes with 500k points

I've been using the 'Vector geometry--> Voronoi ploygons'function in QGIS to create voronoi cells for 200,000 points with success. However, recently I am working with a bigger point set (500,000 ...
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Save output from runalg in PyQGIS

I try to use the build-in Python-console of QGIS to create voronoi skeleton lines from a set of polygons. Therefore I iterate over the features of my input layer (the polygons) and then I use the ...
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2answers
576 views

Constrained Voronoi polygons QGIS

I have a shapefile of polygons, which are effectively borders of a geographic unit (consider as an example the 50 u.s. states, each state has within it some number of points.). I'd like to create ...
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1answer
112 views

Adding vector layer and newly created layer always in Top- Down Order Panel using Pyqgis 3 [closed]

I have two layers in my project Point Layer Building Layer I recently created Voronoi Polygon on Point Layer say (vor-points layer) But as soon this Happen, the newly created vor-points layer ...
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1answer
108 views

Constructing Voronoi Polgon and Applying Nearest neigbour in it

I am learning QGIS 3.XX and currently working on Voronoi Polygons. I have three layers Point layer Building Layer Population CSV file. These points layer are basically water tanks and building ...
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1answer
101 views

If rectangle corner points have same nearest neighbor, does whole interior?

If all four corners of a spherical (but actually WGS84/elliptical) rectangle are closest to a given point p in a set S, does that necessarily mean all points inside the rectangle are also closest to p?...
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1answer
104 views

Voronoi polygon strange result

I am using QGIS 2.18.21. The attribute table of my shapefile has 88 features but after creating the Voronoi, only 86 are in the attribute table and all the points are showing inside the Voronoi ...
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1answer
182 views

Count the number of points in each Voronoi polygon

I have a Data.frame consisting of Longitude and Latitude called Points1, with which I use Voronoi polygon. I also have another Data.frame of Longitude and Latitude called Points2. I then want to ...
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1answer
597 views

Choropleth map from voronoi map from a set of coordinates (d3+leaflet)

I have a csv file with a set of coordinates with the following structure: id,name,latitude,longitude (24 values). Those 24 points represent coordinates in a city. I would like to get a voronoi map ...
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How to generate a Global Voronoi diagram?

Using arcMap, QGIS and similar software it is easy to create a non-global Voronoi diagram. The resulting shapefile polygons however are showing weird behavior when crossing the -180 meridian or the ...
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PostGIS global Voronoi Thiessen Diagram Polygon

I am trying to create a global voronoi diagram for three points (cities): Miami, Boston and Honolulu. The geom column contains the points created by x and y.: | index | name | x | ...
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2answers
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No Voronoi polygons created

I want to create the Voronoi diagram from a set of point (see below). When I use the "Voronoi Polygons" tool from QGIS, there is an error : File "C:/PROGRA~1/QGIS3~1.0/apps/qgis/./python/plugins\...
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3answers
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Growing polygons with limiting area and boundary using ArcGIS Desktop?

I need to create polygons of a specific area based upon random points within bounding polygons, but haven't been able to find a tool able to do all these. I've looked at growing Theissen polygons, ...
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1answer
154 views

Symbology: different ways to display categorised data QGIS 2.16 [closed]

I have a database of 100 entries which has been categorised using a column of data that has 20 categories which essentially breaks up my map into 20 regions. I'm seeking advice on ways how to create ...
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3answers
484 views

How can ST_VoronoiPolygons be used instead of the broken built-in algorithm in QGIS?

I tried to use QGIS to create voronoi polygons from a set of points with an attribute (group) and then merge the polygons with the same value for that attribute. (This last step is what QGIS calls ...
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1answer
212 views

How to define voronoi polygon buffer extend in QGIS from layer extend

I'm using QGIS (2.8.1) Voronoi Polygons Algorithm and I would like to extrapolate them to a polygon layer extend. In order to do this, the tool opens a window asking me to enter a number or expression ...
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Voronoi Polygon Algorithm seems to exclude a Point from processing

I am using the QGIS (2.8.1) Voronoi Polygons Algorithm on a point shapefile. See image below, the red triangles are the points I am using. The resulting polygons miss a part (around HP87). Any ...
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3answers
651 views

Strange results with Voronoi polygons in QGIS

I'm trying to generate a Voronoi Diagram in QGIS 2.14.3 from 16 points. The result looks very strange, at least compared to what I expected. For me, at least the two yellow highlighted split are ...
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543 views

Determining areas on a Voronoi Diagram around a point

I currently have two data sets concerning the Netherlands, one containing longitudes and latitudes of population cores (Hubs) along with other information, such as average house price, and the other ...
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264 views

ST_Voronoi is creating invalid geometries

I have a workflow where I am creating Voronoi polygons from a series of points. However since the polygons on the exterior extend really far out I have clipped them and then joined them back to points ...
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1answer
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Splitting overlap between polygons and assign to nearest polygon using PostGIS?

My question is quite related to the unanswered Split overlap between polygons into disjoint sets except I'm not using shapely, I'm using PostGIS 2.4 on PostgreSQL 10. I have a table containing ...
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1answer
148 views

Thiessen Polygon - geotools

I need to create Thiessen Polygon from a point collection and then intercept them with other polygons. I need to do this from a java program. I'm using the Geotools library. I was able to load the ...
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how to create thiessen polygon around specific areas of interested area? [closed]

I wish to create Thiessen polygon within all sub_basin of my interested area individually, meaning that to create Thiessen for every sub_basin one by one. I have to layer one is point layer and ...
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1answer
81 views

How to fit census tracts within Voronoi Polygons?

I have a map with Voronoi polygons and I need to join census data in it. The problem is that the geometry of voronois and census tracts (CT) do not match. My goal is is to place census tracts (or ...
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1answer
561 views

Voronoi that don't cross boundaries

I have several dozen points plotted across the UK. Each point represents a facility that serves local people. To estimate the catchment areas of each facility I created Voronoi polygons around them, ...
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223 views

Constraining Voronoi polygons to other layer using FME?

Using FME 2017.0.1.1 (Build 17291) is there any way to constrain the extent of created Voronoi polygons to polygonal features of another layer? Instead of clipping the Voronoi polygons after creating ...
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1answer
276 views

I don't understand how v.voronoi GRASS module works with flag -a

I'm trying to use v.voronoi with flag -a. An example in the manual shows Voronoi diagram for urban areas but each try returns: v.voronoi -a --overwrite --verbose input=...
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Fill in spaces between polygon features, voronoi style

I'm looking for a way to merge polygons across the empty space between them with a Voronoi-type result. There is a very similar question here, but the approaches outlined in the comments did not ...