8 votes
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live ellipses around points in QGIS with orginal point still there?

Using the little green plus to the right of the symbol-preview pane add a layer to the symbol, which by default should be a point representing your original feature, as long as you're working on a ...
Erik's user avatar
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8 votes
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Creating buffers to closest distances with two categories in QGIS

You will need the computed distance to classify the output. One option is to create a virtual layer that will compute the distance, record it, buffer the point and that you can style as you wish using ...
JGH's user avatar
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8 votes
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Creating a one sided buffer in QGIS

You can use the "one side buffer" under the tool dialog box, just search for the word buffer. It is under GDAL Vector Geoprocessing tools/algorithms. Take a look at the screenshot below. ...
GforGIS's user avatar
  • 3,126
7 votes

Creating buffers to closest distances with two categories in QGIS

Alternative solution I use Rule-based symbology with the following expressions: For Filter (calculate distances for each point and select distance <0.7): distance( $geometry, array_get( ...
Ingrid Ingravida's user avatar
7 votes

Labeling count points within dissolved buffers in QGIS

This isn't a complete answer but might provide you or others some ideas to combine with other suggestions. Considerations: Assumes you are OK with clustering algorithm approach (not necessarily same ...
she_weeds's user avatar
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6 votes
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Buffer accuracy in virtual layer differs from accuracy in PostGIS view

When using a virtual layer, even over a postgres layer, you are not using postgis functions but rather spatialite functions. We can see that st_buffer, in spatialite, has a default of 30 segments per ...
JGH's user avatar
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6 votes

Buffer/expand point contained inside another polygon

You can use the Geometry by Expression tool on the point layer with this expression: -- create a square buffer (change size as necessary) with_variable('buf', bounds(buffer($geometry, 500)), -- get ...
Matt's user avatar
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6 votes
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Labeling count points within dissolved buffers in QGIS

What is a bit tricky: expressions work on a per-feature basis, so there is no direct way to only label the dissolved buffer (and any indirect way would be too complicated for the task, an overkill). ...
Babel's user avatar
  • 71.2k
5 votes

Fixing holes in the buffered polygon using PyQGIS

Delete holes: Takes a polygon layer and removes holes in polygons Use buffer output as input: layer = iface.activeLayer() buffered = processing.run("native:buffer", {'INPUT':layer,'...
BERA's user avatar
  • 72.6k
4 votes

Dissolve buffers if the intersection/overlap is greater than 50%

If I understand your question correctly, the main challenge is where more than two circles are overlapping at the same time. Based on the closeness of points logic (https://math.stackexchange.com/...
Tom Brennan's user avatar
  • 4,787
4 votes

Creating buffers in meters for locations around the world using Python

You can use .estimate_utm_crs method to find a suitable utm crs for each point, reproject to it and buffer: import geopandas as gpd import shapely buffer_distance = 1000000 #Buffer radius in meters #...
BERA's user avatar
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4 votes
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How to prevent duplicates from being generated in Spatial Join in PostGIS

You could try to select first all the sentinel that meets the conditions and after that create the buffers. You can use EXISTS subquery expression to test if there exists a row in another table that ...
LauriK's user avatar
  • 1,638
4 votes

Labeling count points within dissolved buffers in QGIS

If you want indeed to create one label per buffer, it is easier to indeed create dissolved buffers with the box Keep disjoint features separate checked to get one separate feature per "cluster&...
Babel's user avatar
  • 71.2k
4 votes

Seeing how far you can travel by road using QGIS

Use Service Area From Layer. I want to travel 500 m from each shop point. I've snapped the points to the road layer to make sure they lie on a road then Service Area from layer.
BERA's user avatar
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3 votes

Creating buffer for MultiPolygon that covers all its surroundings in QGIS

The distance parameter in buffer tool is in the units of your coordinate system, so in your case it is in degrees which is bad because one degree at the equator does not equal the same distance as one ...
BERA's user avatar
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3 votes
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How to calculate the average elevation within a certain radius around a grid cell and apply the average to the grid cell in QGIS?

If I understand the question correctly, here's one approach that should work. Convert the raster to points using Raster pixels to points Buffer the points by 15km using Buffer Calculate zonal ...
Tom Brennan's user avatar
  • 4,787
3 votes

Buffer coming out to be a circle

You have most likely set the layer CRSs to EPSG:32643 when you need to reproject the layer to EPSG:32643. If you look at your scale in the second image above, it's 24:1 (ie 24cm on the map = 1cm on ...
Tom Brennan's user avatar
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3 votes
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Calculating percentage of landuse type within buffer using Python

You can use geopandas with union and groupby: import geopandas as gpd landuse = gpd.read_file(r"/home/bera/Desktop/gistest/my_riks_smallsample.shp") landuse_class_field = "kkod" ...
BERA's user avatar
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3 votes
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QGIS Single sided buffer value of specific area and line length on 90 degrees lines

Have you tried to sum up the missing area in all these intersections - add this to the area needed and recalculate?
Niklahrs's user avatar
  • 183
2 votes

Difference between df.geometry.buffer and df.geometry.scale in plain english

import geopandas as gpd import shapely import matplotlib.pyplot as plt geoms = ["Polygon ((716228 7200069, 716072 7198883, 717168 7198760, 716228 7200069))", "Polygon ((714718 ...
BERA's user avatar
  • 72.6k
2 votes

QGIS expression selecting features intersecting single buffer that has certain distance to the buffered feature

Something along the lines of the following may achieve your objective. You haven't specified how the buffer ring is defined. I have arbitrarily given it an outer radius of 1000 and inner radius of 500,...
Tom Brennan's user avatar
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2 votes

How to calculate the weighted average of a raster for the pixels touching a layer corresponding to a buffer (ArcGIS Pro)

The only way I can think of with ESRI software would be to convert all the raster cells to polygons and calculate fractional intersection with a vector intersect deriving a given weighted statistic ...
Jeffrey Evans's user avatar
2 votes
Accepted

Custom Shapely Cap style

You can try creating a triangular polygon and clipping that from a square end buffer: import geopandas as gpd from matplotlib import pyplot from shapely.geometry import LineString, Polygon, CAP_STYLE ...
user2856's user avatar
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2 votes
Accepted

Create road edge network (footpath) using existing road centerlines including junction lines

Here's a starting point for an approach. It uses the road intersection vertices to select the footpath vertices for the junction box, and then minimum bounding geometry to create the junction box. It'...
Tom Brennan's user avatar
  • 4,787
2 votes

Dissolve buffers if the intersection/overlap is greater than 50%

This expression works with Geometry Generator (for visualization only). Unfortunately, you can't create actual geometries with this as aggregate functions do not work with Geometry by expression. ...
Babel's user avatar
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2 votes
Accepted

Single-sided buffer yielding artifacts in QGIS

This is not an answer to how to make a clean buffer polygon for a closed linestring with the single sided buffer function. Instead of using single side buffer, I suggest to use a normal buffer ...
user30184's user avatar
  • 65.4k
2 votes

How to calculate the average elevation within a certain radius around a grid cell and apply the average to the grid cell in QGIS?

An approach that can be done in a single step - though it requires some initial setup - would be to use the UserDefinedWeightsFilter in Whitebox Tools. You will need to install Whitebox Tools Core, as ...
Tom Brennan's user avatar
  • 4,787
2 votes

QGIS Single sided buffer value of specific area and line length on 90 degrees lines

I have solved it by: (area desired + missing area from intersection + missing area outside the interest area polygon) / line length.
Marin Marian's user avatar
2 votes
Accepted

Why the buffer geometry column in the GeoDataFrame is in point form although it's actually in polygon form?

You have a typo in your read_file call. You use parameter layers="buffers" instead of layer="buffers". So: shopping_centre_buffers = geopandas.read_file( DATA_DIRECTORY / "...
Pieter's user avatar
  • 2,041
1 vote

Fixing holes in the buffered polygon using PyQGIS

Since QGIS 3.0 there is another option available by utilization of the removeInteriorRings() method of the QgsGeometry class. Removes the interior rings from a (multi)polygon geometry. If the ...
Taras's user avatar
  • 32.8k

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