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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Voronoi polygons along given border in QGIS
I have a shapefile that contains districts (polygons) of a country. I added centroids to each district in order to create Voronoi poylgons around them. On this new layer, the outlines of the Voronoi ...
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Splitting polygon between its neighbor polygons with Voronoi algorithm using Python [closed]
I would like to split the area of my concerned polygon (the blue one in the middle) between his neighbors polygons and affect each splitted area to a neighbor
My data looks like:
affectid
t
geometry
...
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Obtaining the entire extent of a Voronoi diagram as polygons
I am trying to create a shapefile from a voronoi diagram. Here is the snippet of code used to produce the diagram..
import numpy as np
from scipy.spatial import Voronoi, voronoi_plot_2d
# Array of ...
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Limiting Voronoi polygons with circles
Using the following:
Layer 1: Voronoi polygons
Layer 2: Circles buffer for each points, polygons
When I Cut/Intersect in QGIS, here is what I can get as results.
This is ALMOST what I want.
The ...
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Create Voronoi of different sizes based on mean and SD
I have some large polygons that I want to subdivide into smaller Voronoi polygons.
I am using the very helpful function that someone provided here...
Dividing Polygon into parts which have equal area ...
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Limiting Voronoi polygons from shapely.voronoi_polygons to a shape with extend_to
I'm trying to get some voronoi polygons from a set of coordinates distributed within a country, I don't need said polygons to extend out of the country, I tried using extend_to from voronoi_polygons ...
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Adding names or labels to the Voronoi polygons obtained from shapely.voronoi_polygons
I currently have a dataset in CSV format with around a thousand points, each has a name, latitude and longitude, I'm using those make some Voronoi polygons which in turn I'll later plot on a folium ...
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PostGIS Voronoi not getting properly cut by cookie cutter polygon
I'm trying to create Voronois in Namibia but it seems like they aren't filling the entire country polygon (the one being used as the cookie cutter).
I have tried multiple queries and joins but they ...
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Thiessen polygon delineation within a feature (polygon) not extent
I am trying to create Thiessen (Voronoi) polygons, based on points with a defined shapefile (separated polygons).
The output should be inclusive to the feature. The output I receive now is the ...
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How to make constrained Thiessen polygons in ArcGIS Pro/QGIS 3.26 [closed]
I want to make constrained Thiessen polygons in which the process of calculating polygons will stop when the each polygon touches the boundary line/coastline. How can I do it in ArcGIS Pro or in QGIS ...
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Problem with voronoi library (scipy Voronoi, geovoronoi and libpysal Voronoi)
I'm having problems with several libraries and I can't think of a way to fix the problem. When I perform Voronoi processing. Some polygons are generated "inwards" causing numerous polygon ...
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Voronoi and distance to the nearest point
I was convinced that Voronoi polygons were created so that each location in a polygon is closer to the origin point present in that polygon than to any other seeds
In Snow's famous case study in Soho, ...
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Have voronoi take into account line boundaries (such as rivers, highways...) (on Qgis 3.14)
I have points locating supermarkets. I would like to use the Voronoi method to automatically delineate the catchment area of each supermarket (in real life of course it overlaps a bit on each other ...
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Approximate value of properties based on sold properties in the area
I have a polygon layer in QGIS containing the parcel data for a city and surroundings, and a point layer with information about properties that have been sold recently. Since there are far fewer ...
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Finding which region is nearest to which stations in R
I have a point dataset of 16 places in Switzerland that looks like these and is called stations
stations <- read_csv("station.csv)
view(stations)
Cityid
x
y
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611285.549
267664.109
2
600454....
user204173
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Why can't one build Voronoi regions on only 2 points?
Using Qgis 3.2 or python's geovoronoi, the Voronoi algorithm does not work on 2 points. I expected that the bounding box between the 2 points would have been cut in half but got errors instead. Qgis ...
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Non overlapping buffers/morphological tessellation for polygons in sf
I am trying to replicate the tessellation functionality from the momepy package (see source code here, lines 61 to 550) in R, using sf. This is basically a kind of mixture between a buffer and a ...
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Save the geovoronoi result to file
I try to use geovoronoi in my tasks, following the example from the link on Github. But I can't figure out how to properly save the result to shp or any other vector format. The dataframe didn't work ...
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QGIS: Polygon split by lines not working?
I have a polygon in QGIS consisting of a dissolved set of shapes. My objective is to split this shape using the lines from a set of Voronoi polygons.
To do this I calculated the Voronoi polygons, and ...
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Buffer around lines with varying width in between
My questions is about creating an elongated buffer around various lines and these buffers should run right in the middle of two parallel lines. The problem is that the lines do not have an equal width ...
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'Use Layer Extent' not available in v.voronoi
I want to follow the accepted answer to the question, "Voronoi Diagram on a given polygon using QGIS".
However, in my QGIS (3.16.14-Hannover), in v.voronoi I don't have the option 'Use Layer ...
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Finding parcels directly across street using ArcMap
I have a set of polygons like this:
The broad goal is to find how much of each polygon's perimeter is bordered by each of the other polygons, including polygons across the street. In other words, I ...
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Cropping Voronoi polygons to specific distance from input points using QGIS
The Voronoi polygon algorithm propagates the polygons to the extent of the input layer (the points), which means some massive polygons. The majority of those massive polygons are nonsense data - we ...
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What tool do I need to visualize world map with straight border while keeping its area and neighboring countries
I am fairly new to data visualization.
My goal is:
Turning country area into right angled polygon with same area
Keeping the neighboring country tangent to its new border
Finding the new arrangement ...
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Creating Voronoi for points that consider separated land or gaps in land [duplicate]
As can be seen in the picture, I've created a Voronoi for points in the UK. However, the Voronoi does not take into consideration the split in land in the south-west region of the country. Therefore, ...
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Clipping with Voronoi polygon using QGIS
I'm trying to clip a road network (polyline) with Voronoi polygons. The polyline don't clip but I don't know why. I try to separate my road network according to geographical points collected in the ...
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How can I generate polygons like in a Voronoi diagram/Thiessen Polygons and get the nodes for each of the polygons?
I want to be able to generate a set of polygons where I can extract all nodes for every polygon. For example:
Polygon 1 - (0, 0),(0,2),(2,0)
Polygon 2 - (0, 2),(2,2),(2,0)
Polygon 3 - (0, 2),(5,5),(8,...
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Splitting polygon at points using ArcPy with ArcMap
I am trying to divide irregularly shaped polygons at specific points. I don't have any fields that inform the angle at which the polygons should be divided.
I am using Create Thiessen Polygons which ...
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Correcting Thiessen Polygons output from ArcMap
I am try to divide irregularly shaped polygons at specific points. I don't have any fields that inform the angle at which the polygons should be divided. Based on the Split polygon based on point ...
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PostGIS Voronoi Polygons with extend_to parameter
I am creating voronoi polygons for locations inside a country, using PostGIS.
The function creates these areas for ~80,000 locations in less than a second.
However, I can only get the polygons to ...
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Creating polygons based on point layer using QGIS
I have a point layer of residential coordinates which includes an attribute field indicating the most visited hospital for the people living at the coordinate. From these data, I want to create a ...
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Characterizing polygons that are created when joining 2 vector layers [closed]
I am using QGIS for the first time.
I have a map of an aquifer with 2 different vector layers that split the aquifer differently into several polygons. In the first layer, I used some points(measuring ...
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Copying a field (column) value from a Voronoi polygon into the point inside that polygon
I'm relatively new in GIS and I am using QGIS. I'm trying to find a way to copy a field value from a voronoi polygon layer into each point that is currently inside the said polygon.
Each voronoi ...
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Unpacking Attributes from OSM
I am an Amateur user of QGIS and just started using OSM data as a part of a project where I need to create approximate postal code boundaries.
I used QGIS with OSM data to create Voronoi Polygons, ...
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Hard line-barriers for Thiessen polygons
Similar to Creating polygons from points using lines as barriers, which has not been resolved; plus, the scenario is slightly different.
I have one dataset with 60,000 points and one with boundaries ...
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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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Making polygon for every point in set using Voronoi diagram
I'm trying to make polygons from points, where 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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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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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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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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3
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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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