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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ArcGIS Pro Symbology: Polygon boundary is displayed at the wrong size
This feels like a silly question, but ArcGIS Pro is displaying the boundaries of my polygons as very wide. Any suggestions on what settings to change to put it back to normal?
Image 1 below is the ...
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Adding new polygon attribute column based on location withing another polygon in R
I have here an example with two layers - one containing two large polygons Pol_large, and second containing 4 small polygons Pol_small. For Pol_small
I want now to find the location of each of the ...
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Downloading Polygon/Administrative Boundaries using WikiMapia
Is there any way to download administrative boundaries / polygons for a small city through Wikimapia?
I tried to download the boundaries but the results were points not polygons.
I need to download ...
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Buffering every polygon in layer
I'm trying to use the "Fixed Distance Buffer" from the Processing Toolbox to create a 500m buffer around all the woodlands in my layer, but the tool only puts a buffer around the smaller woodlands.
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Keep getting NAs when I run sp's over function on LatLon points on shapefile polygons
I am not sure why i am keep getting NA whenever I run the Over function with Latitude and Longitude point on the polygon from shapefile. Please note that this is first time for me doing the spatial ...
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Intersect of all polygons from the same layer in QGIS
I have various polygons within one layer in QGIS.
As a result I need the area where all polygons overlap as shown in the picture.
Is there a way to do?
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Finding zipcodes within line using GeoPandas [closed]
I have a shapefile of Houston zip codes and gdb folder of lines (within Houston).
The lines are in a gdb folder containing over 125 files. The types of files included in this folder are GDBINDEXES, ...
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How can I make a heatmap of polygons using a graduated color scheme in QGIS?
I want to make a heat map of species biodiversity like the people did in the picture below. I can sort of get it to work by setting my layer with multiple polygon subclasses in the Layer styling panel ...
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Eliminating sliver polygons automatically [closed]
I have thousands of sliver polygons outside of my study area. What is the best way to eliminate them automatically? In ArcGIS or QGIS.
Those polygon islands are an example of the slivers.
Note: I can´...
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OpenLayers fill opacity increases after repositioning [closed]
I have created a test project where i'm trying to learn how to work with OpenLayers. I try to do a get request to a remote geoservice. Every time I reposition the filled polygons on my map get there ...
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How can I get a polygon of everything between two polygons in PostGIS?
I am trying to find all the neighborhoods located between two (or more) neighborhoods. The definition of between is obviously a bit fuzzy but for our purpose, I'd like to extract all neighborhoods ...
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QGIS - Use polygon orientation to rotate texture inside polygon
I'm trying to fill entities (polygons from 3 to x points) with a texture that I want to align with the 'general' orientation of each polygon, ie, I need a formula to assign to the Rotate field of the ...
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Joining two polygons that have information in same spatial location using ArcMap
I am using ArcMap 10.6.1.
I have two shapefiles, one that has human disturbance and one that is fishnet grid and every grid has a unique value. I used the fishnet tool on my human disturbance ...
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Cut one polygon into smaller polygon with other polygons
I want to use one layer with numerous polygons in it (layer 2 in attached image) to cut a big polygon on another layer (layer 1 in image), so that said big polygon is separated into smaller polygons.
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QGIS 3.10.3 crashes removing a polygon layer created via script
I created a polygon layer from a line layer(qgis:linestopolygons), set its style ('qgis:setstyleforvectorlayer') and put it in a group of layer table.
Everythings works but when script has completed ...
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Populating linestring column based on other table values (OSM nodes/ways)
I'm trying to populate a linestring column using points from another table.
After reading a lot in this site and many experiments I'm still stuck.
This is the table which I want to fill the road ...
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Keeping same color when using "gdalogr:polygonize" function to polygonize segmented image
This is one example of images that I have:
Now I want to polygonize it to get shapefile of different polygons. Every time I run this algorithm I get polygons of different colors but I want to keep ...
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Identifying zip codes that cover multiple townships
I have shapefiles with zip code tabulations in Massachusetts and township areas. Some zip codes fall completely within a single township, while some zip codes cross multiple town borders. I want to ...
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Clipping complete building/closed polygons only from polygon shapefile using QGIS
I have a polygon layer of buildings and a polygon layer of AOI. Now I want to clip only complete/closed polygon that falls within this AOI.
As you can see there are certain buildings that have a ...
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Fill out irregular grid with polygons
I'm using QGIS 3.10.0 A Coruna.
As you see in the picture, I have an unregular grid with some buildings on them. I would like to fill out all the other rectangles between the points with a polygon ...
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Kriging for Soil Nutrient Analysis
I have collected soil analysis results on a gridded basis within fields. These grids were generated on a 35m based upon digitised polygons of the field extents.
I have imported my soil analysis ...
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Spatial similarity between polygons
I am using PostGIS and python3. I have a table with polygons objects, the polygons have year as an attribute. I need to identify the uniqueness of the polygons trough time. For instance I need to ...
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Enlarge the size of multiple polygons contained in a shapefile QGIS
I have a shapefile which contains many polygons and because I work on a large geographical extent, I'd like the polygons to be slightly bigger, for presentation purposes. Basically keep their extent ...
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Weird problem with st_polygon in the sf package
I would like to create a simple polygon using the sf package.
From my understanding, I have to create a two column matrix where the last row is identical to the first one to close the ring of the ...
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Model or script to calculate distance from each point in a multipoint file to the center of a matching polygon in ArcGIS Pro
I am working in ArcGIS Pro. I have a series of multipoint features that represent release locations for individual animals. I have a series of these, for multiple study sites. At each study site - I ...
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Extract IDs from polygons intersecting with other polygons
I'm currently building a model where I have to extract all IDs from the red outline polygons containing the green polygon.
In the provided example I would like the green highlighted polygon to get a ...
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Calculating list of existing polygons with distances from newly created QGIS/PostGIS
I have two polygon tables (SRID=4326) in postgres: t_areas and t_sites. Once I insert through QGIS 3,8 a new area in t_areas I'd like PostGIS (by a trigger) to list all sites within a certain km range ...
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Calculate volume of MultiPolygon Z using Postgis
I am trying to calculate the volume of a multipolygon z using Postgis.
SELECT ST_Volume(geom) from grb;
And I get this error:
MultiPolygon is invalid : Polygon 0 is invalid: points don't lie in ...
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Selecting features inside a polygon - PyQGIS
I have just started working with PyQGIS and I would like to ask this question. I have a rather big dataset (cell phone towers) and I want to narrow it in the towers that exist inside a certain ...
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Looping through list of coordinates to create polygons on Google Earth Engine
I have imported a CSV file with just one column. Each row of the column has multiple coordinates required to draw a polygon. (This was collected on the ground)
I have used the below code to extract ...
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Adding border style to country which has geometry type polygon? [closed]
I have a drop down list and when I select a country name and the map goes to this country, I want to add a specific border style to this country (polygon geometry).
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GRASS v.transform tool producing no results QGIS
I'm working on a simple polygon feature representing the Western Cape province of South Africa. My goal is to enlarge the polygon so it can stand out from the others.
To do so I've used the v....
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How to create Polygons of a specific size?
I'm trying to create polygons of specific size in square meters that represent the areas surrounded by roads. The roads are stored in PostGIS as points / lines. If required, I can convert the data to ...
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Combine multiple polygons into a single one (with holes)
I have the following GeoDataFrame with multiple polygons which represents a single area (raster_val = 1.0) with holes in the middle (raster_val = NaN):
geometry ...
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Creating Latitude & Longitude from polygon shapefile using QGIS
Could you help me to create long & lat (x and y coordinates in degrees) for polygon shapefile?
When I used directly QGIS export vectors to csv file, it didn't work.
Here is the example file: ...
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Maintaining coordinates when converting SpatialPolygonsDataFrame to simple feature in R
I am ultimately trying to determine the area of a home range, but I need to remove areas that overlap land. To accomplish this, I have calculated and plotted my home range, and want to use one polygon ...
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Extracting SpatialPolygonsDataFrame attributes into a dataframe in R. Assigning new vars based on other polygon in R
Here you can see a group of small and large polygons. Small polygons are cropped as I am only interested in their properties, such as size inside the large polygons. I have two furhter objectives ...
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QGIS alternatives to GDAL contours to polygons
I have Windows 7 running 3.10.2-A Coruña. The only success I have had in creating nested polygons from a raster dataset is using GDAL with -p to create polygons. However, I recently cancelled the ...
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Check if shapefile Polygon has a valid number of points - Python [closed]
I'm trying to create a polygon from ShapefileReader.shapes() object in python using the shapely.wkt library. But I'm having the followeing error:
IllegalArgumentException: Invalid number of points in ...
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Why is a vertical polygon defined by WKT PolygonZ invalid?
Can you tell me, why this PolygonZ is invalid?
PolygonZ ((409662 5317369 285, 409662 5317377 285, 409662 5317377 302, 409662 5317369 302, 409662 5317369 285))
The polygon is completely vertical, but ...
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Which method to find intersection between lines with polygon
How could you find intersection between lines intersected with polygon?
I want to find the lines only that located inside the map and intersected with polygon then change the colour of intersected ...
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Find lines whose both start and end point ends in a polygon
I have a river dataset, which is dissolved, so between two lakes there will always be one single river line.
Now I want to find all rivers that starts in a lake, and ends in a lake. So if my rivers ...
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Where is the "Intersection" tool located in QGIS 3?
I would like to generate the intersection between lines and polygons lines and polygon in QGIS 3 and extract the id number for each line. I would like to assign a red color to the resulting lines ...
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Aligning Polygons to Margins in Data Driven Pages
I'm creating a data driven page of polygons (forest subcompartments) on a basemap in ArcMap 10.4.1. The scale required for outputted maps is predefined (1:5,000). Output is multi page pdfs.
Users of ...
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Merge donut with its hole
I have a layer with polygons in QGIS. The one selected on the bottom has a hole in it, the hole is also a shape. So I have the donut and his hole. How can I merge these two polygons?
EDIT: I didn't ...
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Different Results in GEE when using manually upload polygon and uploaded shapefile
I have a code that classifies polygons based on their NDVI values (based on mean and std, classes into 3 ranges: high, medium and low).
The code suppose to do this process for each polygon, but I ...
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Simplifying a multipolygon into one polygon respecting its outer boundaries
I have a multipolygon containing a one large polygon, itself containing a number of smaller polygons, which constitute 'holes' in the largest polygon.
My goal is to simplify the multipolygon into one ...
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Close gaps between some polygons, which are adjacent in reality
I have tens of thousands of polygons (farmer plots) which have been measured while on the fields. This has caused plenty of gaps between some polygons, which is not the reality. I would need to close ...
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Converting polygon to line in QGIS
When I'm doing "polygon to line" analysis on ArcGIS the result is individual line features but in QGIS is not.
How can I execute "polygon to line" in QGIS where each polygon becomes individual line ...
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Quartile calculation option in QGIS?
I need to calculate the quartile value (e.g. 75%) of the pixels of a raster layer within a polygon file. I try to do that using QGIS, and found that the zonal statistics might be able to do that. But ...