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1 vote

Counting points within certain distance of each other in QGIS

Try also the "DBSCAN clustering" geoalgorithm. It contains a setting called 'Maximum distance between clustered points' and will provide in the end the "CLUSTER_SIZE" attribute.
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0 votes

Request attribute information from multiple polygons below a point

One Join attributes by location for each polygon layer using the output of each as input to the next. Either manually or using a model:
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1 vote

Why the center points created from center of pixels in ERA-5 dataset are not appear in correct places when exported and showed in ArcMap?

Notice that the points are in a particular different place: the exact corners of the pixels. I'm not familiar with the relevant standards, but I think I've heard about georeferencing of images being ...
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3 votes

Finding distance between points using Python

As @Vince notes in a comment: Your query asks for the distance between a point and itself, so zero is the correct answer. If you want to compare each point with the other points you need to nest the ...
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0 votes

Creating line layer from point layer with start and end attributes in QGIS

You could edit your csv file to create a new field containing the WKT for a linestring. This could be accomplished using a spreadsheet program, a text editor, or any other method. Then load the CSV ...
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2 votes

Calculating minimum distance between points in QGIS

The Distance matrix algorithm currently uses a Cartesian spatial filter based on the CRS of the target layer to find the k nearest points, and calculates the ellipsoidal distance for only those points....
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1 vote

Point vs Multipoint and table join using QGIS

If your pieces have individual (non-spatial) attributes, such as when the piece was found, an important number for the piece, or who found that piece, then you should use POINT geometry and then each ...
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6 votes

Counting points within certain distance of each other in QGIS

Open the Field Calculator and use this expression: aggregate( 'Point_layer_name', -- replace with the name/id of your point layer 'count', $id, filter:=distance( $geometry, ...
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1 vote
Accepted

Exporting data from points to a polygon

One of the key features of GIS is to be able to do a spatial join. So you don't need a primary key like you would in a standard relational database. You can use QGIS to do a "spatial join" ...
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2 votes

Saving "on mouse click" created markers to be available after reloading the browser in Leaflet?

As @Keagan Allan pointed out in his answer you have to somehow save info about newly created markers to be available during page reload/refresh. You can use browser session storage for that, using ...
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0 votes

Saving "on mouse click" created markers to be available after reloading the browser in Leaflet?

My understanding of Leaflet and Javascript is limited, but you will will need to store the map clicks for the markers in a local datastore, such as a GeoJSON file and load that GeoJSON every time you ...
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1 vote

Find points which fall within specified distance to POI using Python

You can create a dataframe of one point, buffer the point and spatial join it to all other points. Spatial join is very fast. import geopandas as gpd df = gpd.read_file(r'/home/bera/GIS/Data/LMV-...
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0 votes

Counting total number of points within polygon (Buffer) layer using ArcGIS Pro

You could join your polygon layer into a single polygon feature. Or more straightforward, when you create your polygon Buffer, you can set the dissolve type to "Dissolve all output features into ...
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0 votes
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Offset points in QGIS using attribute values for Bearing and Distance?

Yes, it can be done. I bet QGIS has a neat method or tool to do this but I don't know it, so I did it manually. I assumed the distance is given in meters... First convert the data into a local ...
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  • 477
0 votes

Groupping points to clusters containing similar number of features using QGIS

At least theoretically, another approach that could produce something close to the desired result is based on voronoi polygons and cartograms. However, cartograms for this amount of features are hard ...
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0 votes

Groupping points to clusters containing similar number of features using QGIS

I found a way to achieve at least in part what I want to do, even if it is not an exact workflow, more a heuristic approach. So I would still be glad to get better solutions. What this solution does ...
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0 votes

Extracting raster values at points using Open Source GIS?

You can use Sample Raster Values from the Processing Toolbox in QGIS. This algorithm creates a new vector layer with the same attributes of the input layer and the raster values corresponding on the ...
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5 votes
Accepted

Adding/concatenating multiple values in column when using line intersections in QGIS

Use the Field Calculator with this expression: array_to_string( array_sort( array_distinct( overlay_touches( layer:='lines_layer_name', --specify the name of your line layer ...
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0 votes

Add another set of coordinate values in the same point entity in QField (line start and end)

For a line type layer, with ESPG:4326, you can use: replace(geom_to_wkt(start_point($geometry),5),map('Point (','',' ',',',')','')) replace(geom_to_wkt(end_point($geometry),5),map('Point (','',' ',',',...
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0 votes

Creating path between many points in Google Earth

In QGIS the tool Points to path do this (Example here: https://www.youtube.com/watch?v=U4ecutybI0w). You need to specify the field containing the order in which the points will be connected. You can ...
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  • 377
2 votes

How to parameterize the PointSymbolizer in a SLD Style?

If I get your request correctly, you're looking for a special customization of SLD (not standard) that is called "dynamic symbolizers" in GeoServer. See this old blog post about it (very old,...
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9 votes

Building the shortest route through all points in QGIS

What you're looking for is called "Travelling salesman problem". Let's assume there are a point layer and a polyline layer, see the image below. There are several approaches available: ...
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  • 24k
2 votes
Accepted

QGIS Offset Points by value

You can use the Expression String Builder on the Offset X, Y of the Label Placement using something like Array("distance",0). If the distance is in meters use Meters at Scale for example. ...
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2 votes

Calculating region pair distances along network in QGIS 3.22.4

For those of you looking for a solution to this problem: I found that the QNEAT3 plugin's OD matrix worked for me. See the documentation for more details: https://root676.github.io/OdMatrixAlgs.html
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2 votes

Creating lines indicating the shortest distance points to line in QGIS

There is a plugin for QGIS called Networks and a function in it "Connect nodes to lines" does what you need. The plugin is accessible in the Processing Toolbox after its installation. There ...
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