Questions tagged [polygon]
On a map, a closed shape defined by a connected sequence of x,y coordinate pairs, where the first and last coordinate pair are the same and all other pairs are unique.
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Trying to match building(s) to lot(s) when data has margin of error
I have a set of building and lot GEOJSON data that I want to match and see which buildings sit on which lots.
The problem is that the government data that I obtained has a significant margin of error ...
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Leaflet - I want to delete a segment from a polygon and split it into a polyline or a polyline into two polylines
What I'm trying to do is have a button to delete a segment from a polygon, or a segment from a polyline. I tried attaching an eventlistenner to each segments I find in the in the drawnItems. I take ...
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How to assign tuple contents to individual variables
I have a code that creates a POLYGON. There a 5 points representing 5 x/y pairs (the last being a repeat of the first to 'close' the polygon.
I can produce it either as a shapely polygon or a standard ...
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Finding distance between two first vertexes of line in QGIS
I need to know if there is an expression, or tool to perform the following operations: extract the distance (2D or 3D), between the first two vertexes of a line or polygon.
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Extracting coordinates from shapely geometry polygon with PyQGIS
I have the following code to generate a polygon from some calculated points (x/y pairs a,b,c,d) and rotate it by a given angle (Line_Head) around a given point (Rot_Point). This works.
""&...
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Saving polygon layer with custom forms in QGIS
I make a lot of polygons to calculate the area of different land use types in my work. To do this I usually custom form by opening properties > manage custom forms and field editor configuration &...
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Filtering polygons by name in one column of QGIS Attribute Table
I have a file geodatabase of the ranges of every bird species on Earth, but I am only interested in a subset of 538 of them for which I have data relevant to a study on sexual dichromatism.
The ...
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Creating new and separate layer from hole(s) in multiple layers in QGIS
I am trying to create a new layer that fits perfectly into the hole in the picture below. All of the orange shapes are different layers.
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How would you "normalize" or find the "average" shape and size of a group of polygons? [closed]
I work with RF propagation data, primarily small cells. These cells can have a very different footprint based on the "clutter" or stuff that is nearby. However, I want to find what the "...
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Calculating area of intersection of two segmented polygons in QGIS
I have two sets of polygons. One contains villages, the other farming areas.
There can be several farming areas in one village. Crucially, there can be cross-village farming areas.
My approach to get ...
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ST_ReducePrecision PostGIS function throwing an error
I'm using ST_ReducePrecision in PostGIS to lower the tolerance of shapes so they can be read by ArcMap.
I'm applying ST_ReducePrecision(shape, 0.0001) with a tolerance of 0.0001 to match ArcMap's ...
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Convert polyline features to polygons given the attributes using ArcGIS Pro
Is there a geoprocessing tool or a technique in ArcGIS Pro to convert polylines (A) to polygons (B) taking into account the attributes?
The geoprocessing tool "Feature to Polygon" allows ...
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Dissolving polygons within other polygons and accumulated one of their values in QGIS
I am planning a district heating system (pipe system in red). For this I need the total heat consumption of all cadastral units (in blue) next to the pipe to calculate the dimension. There are zero to ...
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Rounding vertices of polygon to fixed number of decimal places in QGIS
When I digitize a polygon and snap to existing features, sometimes the coordinates end up very slightly away from where I want them to be for example 15.000000099, rather than 16.
Is there a way to ...
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Preserve original number of closed/not-closed points to a shapely Polygon
In the following code:
from shapely import Polygon
a = Polygon([(0, 0), (0, 10), (10, 10), (10, 0)])
b = Polygon([(0, 0), (0, 10), (10, 10), (10, 0), (0, 0)])
print(f"{a=}")
print(f"{...
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Split polygon at narrowest points
I have a massive polygon that looks like this :
This is only a snippet of it. Given its size, it would be best to split it at its narrowest points. I've tried finding a potential solution for this ...
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Create centerline of polygon in QGIS
I have building wall layer, and I want to extract the center line for generate the line of wall, as shown below, left is the origin polygons(complex multiple polygon with holes), red lines in the ...
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QGIS 3.28.9 crash when using Random Points in Polygon
I'm trying to create points in a raster layer of livestock chickens data. After creating an output raster with the values of interest, I used the Polygonize tool to vectorize the output raster. At ...
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Removing true holes in a doughnut polygon
I want to create small cuts to open the holes in a shapefile, while the cuts should be contiguous without affecting the main shape and size of the polygons. The goal is not to have any true holes in a ...
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Selecting multiple sections within polygon to create multiple separate polygons in QGIS
I have a large polygon split up into many different sections. Each section has an ID number ranging from 1-13. I want to be able to select all polygons with a certain ID, and then create a separate ...
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Creating new layer that shows the number of intersecting vector layers at each point in QGIS
I have a QGIS project file with over 50 layers, each representing a different species' habitat range.
I would like to create a new layer that adds up the number of layers at each point in the map and ...
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Merging two (or more) selected objects in GeoJSON file within QGIS
I need to merge two selected, but spatially unconnected, polygon objects into one polygon object within QGIS. They both have the same attribute value within the one attribute field. The file is a ...
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When moving vertex node, change the shape of each polygon that contains this node in QGIS
I digitized a surveyor's map, creating many polygons in a 1:7000 scale so that all points are almost in their correct location.
I switch to a 1:1000 scale, both image and QGIS screen and want to fine-...
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In PostgreSQL how to build polygons using lines around each dot
Probably a bit hard to explain but hopefully the image can explain better
There are 2 datasets, one is a point, the other is a line. Intended outcome is having polygons based on them
The lines form a ...
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Error: Error: SaTScan in the continuous Poisson model
When I run the analysis using the continuous Poisson model in SaTScan, defining the polygon as everything within the distances between the furthest points on the map, I get the following message: &...
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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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Python: Split Polygons where they overlap one another [closed]
I have a python script that produces a shapefile of polygons, created primarily using geopandas.
I wish to split polygons where they overlap each other. Ideally removing all but one feature where ...
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Reducing decimal places of coordinates in vector data using QGIS
I have polygon vector data, some of the polygons are imported from another 3D program (Agisoft Metashape). The imported polygons have up to 12 decimal places in the displayed coordinates (attribute ...
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Convert ~14500 features into ~500 bounding boxes covering at least the same area in QGIS
I downloaded a shapefile from OpenStreetMap that covers all ocean and coastline.
This consists of around 14500 features. What I am trying to do is generate a number of bounding boxes (say 300-1000) ...
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Grouping data points based on proximity and minimal count of attribute in QGIS
I am using QGIS to map animal counts on farms in the Midwest US and using a circle polygon to show where there are more than 30,000 animals between all the farms in that specific area. Each data point ...
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Merging attributes from line layer and polygon layer in QGIS
I am using QGIS 3.32 and have a grid layer with hexagons (so polygons) and a line layer. I would like the hexagons, which are overlapping the line layer to "take on" the attributes of the ...
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Filter polygons to find those which can contain specific dimensions [duplicate]
I have a dataset containing a large amount of polygons which act as potential locations for someone to park a van. To find the polygons that are suitable, they must be able to contain a 11.5 x 6.3 ...
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Rendering polygon by two variables in QGIS
I have a set of polygons with two variables "variable 1" which can take values A, B, C, D, and E and "variable 2" which can take values V, W, X, Y and Z.
I would want to render the ...
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Query to extract addresses in several parts of Germany is not working via QuickOSM
I a trying to extract addresses from the OpenStreetMap as polygons via QuickOSM using the keys: addr:street, addr:housenumber and addr:city.
That works quite well, but not in every part of Germany. ...
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Extracting border from shapefile and then calculate distance to the border
I started with a states boundaries shapefile. I want to extract a part of state border and then calculate the distance of village centroids to the nearest point on this border. I have already ...
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Looping through folders to find shapefiles and then merge them
I am trying to merge shapefiles into one shapefile by looping through folders. I merge them one by one by iterating through each file then merging it with an empty gdf that I set with columns that are ...
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Combine dissolve aggfunc and lambda function
I am looking to aggregate different polygons and applies analytical functions at the same time.
I have tried:
df.dissolve(by=['ville','arrondissement','quartier'],
aggfunc={'transaction':'count','...
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Split a polygon in many parts by areas of specified values [duplicate]
I try to split a polygon in multiple parts based on known values. For example, if I have a 1000 sqm polygon i need to be splitted in 4 polygons (100 sqm, 600 sqm, 50 sqm and the rest of the polygon).
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ST_GEOGFROMTEXT Multipolygons converted to Polygons in BigQuery
I've stumbled upon an intriguing issue while working with MultiPolygons in BigQuery. When utilizing the ST_GEOGFROMTEXT function to parse a MultiPolygon containing multiple polygons, the output ...
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How to identify polygons in contact with other polygons with a shared boundary of at least 3 meters in QGIS?
As part of my Master's Thesis, I deal with the development stages of unbuilt building land. I intend to divide the units of unbuilt building land within the selected settlements into 5 levels and for ...
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QGIS - Delete lines resulted from Symmetrical Difference/Clip
I used the symmetrical difference command with two shapefiles but the resulting layer containes lines due to minimal differences (see example picture below)
Is there a way to automate the removal of ...
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MultiPolygon to Polygon in Python [closed]
I need to change geotype from MultiPolygon to Polygon. Most of the original features are Polygon, but are automatically imported through API as MultiPolygon. How can I change all the types ...
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Setting map extents in print composer using a polygon layer?
I have a group of data points that need to be encapsulated within different polygons. I have used the geometries by expression tool to generate a layer of these polygons. I'm trying to feed the ...
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Centreline for vectors
I'm trying to get a centreline representation for some polygon output from OSM but having tried the approach in this post (Skeletonize vectors in QGIS/Python) I'm getting very odd results. Here's the ...
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Calculate ratio of 2 polygons using QGIS modeler
Working with QGIS modeler, I need to do some arithmetic operations with some polygon areas.
Let's say there are 2 polygons in layer A and layer B. And I'm inputting them into the model using Vector ...
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"ERROR: 22001: value too long for type character varying(6)" for polygon shapefile
I am facing an error
ERROR: 22001: value too long for type character varying(6)
while uploading a shapefile to online govt. portal. When I asked the person only mentioned that there is problem with ...
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QGIS - find overlapping areas between polygons and retrieve id per polygon
I'm having trouble understanding how to find overlapping areas between two polygons (using QGIS, but I'm open to coding if it's any easier), and obtain not only the output polygon, but also which ...
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"Add Polygonal Object" button does not appear on toolbar
I use QGIS 3.36.2 and I would like to create Polygon by drawing directly on the map. So I would like to use the "Add Polygonal Object" button while edit mode but there is no one on my ...
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QGIS - divide inside of polygon into smaller defined polygons
I have the following polygon in QGIS. It is roughly 260m x 20m
Within it, I would like to create smaller polygons like so in QGIS:
12 - 20ft rectangles
15 - 40ft rectangles
^ for 7 rows
(very badly ...
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Creating a vineyard map with QGIS
I'm trying to plot dots (the vines) in an irregularly shaped polygon. they are in parallel rows spaced 1.4 m apart and the vines are spaced 1.2 m apart. The rows are at a 45º angle from N. I tried to ...
