Questions tagged [centroids]
In geometry, the centroid, geometric center, or barycenter of a plane figure or two-dimensional shape X is the intersection of all straight lines that divide X into two parts of equal moment about the line. Informally, it is the "average" (arithmetic mean) of all points of X. The definition extends to any object X in n-dimensional space: its centroid is the intersection of all hyperplanes that divide X into two parts of equal moment.
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Moving features of different geometries at the same time in QGIS
In QGIS 3.34 I would like to move a point feature and a polygon feature at the same time.
The polygon is a round buffer around a point. I am only able to edit the point and polygon one after the other....
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QGIS Radial Flow map: How can I move a centroid point to the middle of a country?
How can I move a centroid to a centre of a country in the QGIS world map and doing a Radial Flow map as described here: https://www.youtube.com/watch?v=dEHMnioynN8
As I understand
You create ...
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Creating radial lines from center of polygon to edge in QGIS
I have a set of polygons for which I need 16 radial lines each from the centroid of the polygon to the edge (see image). So far I have only found a python script to create radial points for a circle (...
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How to find PLSS section corners, given the ring of nodes?
Given a ring of nodes and centroid representing a US Public Land Survey System (PLSS, or Canada DLS) section, find the four corner nodes.
Do the same, but without needing the centroid.
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Splitting polygons though centroid like Pizza Slices in QGIS
I am aware of how to create centroids and how to divide a polygon by line, but not how to create those lines from each centroid.
I was wondering if anybody knows a technique/algorithm/plugin that ...
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Drawn centroid with function make_circle
I'm using the following function to draw a circle at the centroid position of a layer of points grouped by the "ID" field and excluding NULL values:
make_circle(centroid(
concave_hull(
...
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Selection by Location with Have their center in - GeoPandas
I have two polygon GeoDataFrames. I have read them in with the following:
import geopandas as gpd
poly1_path = r”.\Input\poly1.shp”
poly2_path = r”.\Input\poly2.shp”
poly1 = gpd.read_file(poly1_path)
...
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Can I utilize vectorization to improve performance instead of iterating over QGIS Features?
I am using Python to write a standalone application with QGIS. The application uses requests to allow the user to update a shapefile from the internet on demand. After fetching the shapefile, I need ...
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Export all polygons to SVG using QGIS
For a game, I needed to draw the districts of my city in QGIS. I created a layer and drew many polygons on it.
I have now a table with four columns, being "fid", "name" and "...
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Multipolygon to Points
I'm currently mapping out around 10 layers worth of polygons all in a polygon feature as shown in the image below.
I'm now trying to create a heatmap for each layer to show where lies the highest ...
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Centroid data points for US states
I need to map some data related to states in the USA. I have polygon data for each state but my dataset needs to be mapped by points.
How do I find centroid points for each state (not polygons)?
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Creating centroid layer from selection using PyQGIS
I'm trying to create a centroid layer from a selection with Python.
I manage to make a selection based on features with expression :
code_com = '001'
section = '\'0A\''
numero = '0502'
layer = iface....
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mviewer/OpenLayers: Create proportional circles from the centroids of each polygon in a layer
I have created a mviewer map. This one is based on OpenLayers 7.1.
I created a map from a point layer added as WFS from my GeoServer. This layer shows the population using proportional circles.
The ...
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Convert centroid data to lat/long coordinates
I have a geoJSON file from Alameda County, California, that says it is based on "crs": { "type": "name", "properties": { "name": "urn:ogc:def:crs:...
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QGIS: centroid of polygon layer
I would like to determine the center of this layer, when I look for the centroid I get the centroid of each separate shape but I want the centroid of the total layer.
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