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Leaflet v1 plugin: layer control for ungrouped, grouped, and nested-grouped layers

I need a Leaflet plugin which extends L.Control.Layers. I have the following requirements: works with Leaflet 1.x handles ungrouped layers alongside grouped ones handles nested layer groups does not ...
Tom Chadwin's user avatar
  • 5,862
15 votes
0 answers
1k views

High PostgreSQL/PostGIS memory and disk usage when saving QGIS project

Why would simply pressing the Save button in QGIS cause my local PostgreSQL instance to cause memory and disk usage to spike to "Not Responding" levels? Seems to me like the PostgreSQL ...
RyanKDalton's user avatar
  • 23.1k
14 votes
1 answer
790 views

Remove reference to raster layer object PyQGIS

I am developing a plugin to load a set of raster files on QGIS. When there is a large number of files to be loaded, the main UI freezes. So I use QgsTask to move the creation of raster layers to a ...
mdc's user avatar
  • 156
13 votes
0 answers
3k views

How to prevent cross-world lines in ggplot world map?

I'm having issues displaying 'great circles' paths and polygons in ggmap, an extension of ggplot2. Please enter the following code to replicate my issues: https://gist.github.com/Robinlovelace/...
RobinLovelace's user avatar
12 votes
0 answers
493 views

Saving ArcGIS Pro symbology to PostGIS DB for each layer

I want to have a default style/symbology assigned to each layer in a PostGIS database so that whenever it is loaded in ArcGIS Pro, it will come up with the default style. There is a way in QGIS to ...
ar-siddiqui's user avatar
  • 1,768
12 votes
0 answers
1k views

PyQgis Exporting Print Layout: "ERROR 6: The PNG driver does not support update access to existing datasets."

I am trying to export a .tif loaded into a pre-configured print layout template and further exported as .png def openLayer(project, fp, basename, vector=True): layer = QgsVectorLayer(fp, basename) ...
Teabubblez's user avatar
12 votes
1 answer
831 views

Calculate volume of space defined by multiple overlapping 3D polygons

I have thousands of 3D polygons scattered in space but they mostly overlap with many of their neighbors in big extent. Is there any way how to compute volume they define effectively? I would love to ...
vildead's user avatar
  • 231
12 votes
0 answers
399 views

Processing post-execution script hook to clear scratch layers?

I've been cobbling together some Processing scripts for QGIS 2.18 (I'm not a fan of QGIS 3 scripts), and I keep running into one particular problem: my script creates a lot of scratch layers and they ...
Nick_W's user avatar
  • 575
12 votes
0 answers
361 views

ESRI Runtime Geodatabase Shape storage

Does anyone out there know the geometry storage encoding for ESRI's Runtime Geodatabase (.sqlite) format? aka mobile geodatabase. There are 'GDB_ tables', 'st_ tables', 'RTREE indexes' and other ...
Random Geo guy's user avatar
11 votes
1 answer
902 views

How to use a custom function inside GEE ee.Reducer?

I have generated a segmentation using SNIC on GEE and calculated some statistics/features for each segment, using ee.Reducer e.g. mean, std, median, etc. I want to calculate more features based on my ...
Federico's user avatar
  • 367
11 votes
2 answers
2k views

QGIS GRASS Processing Not Working on MacOS?

Recently upgraded to QGIS3 (3.0.2) for MacOS (High Sierra) and encountered GRASS (7.2.2) issues. Tried adding a custom variable and now when running GRASS algorithms (e.g. r.reclass) I get the ...
Gidget1's user avatar
  • 111
11 votes
0 answers
589 views

MapScript with Python 3

I am trying to build raster summarizing features into a GeoDjango webmap, and would like to use the django-raster and django-wms packages to do so. I believe that I have them set up correctly, but am ...
jbukoski's user avatar
  • 1,297
11 votes
0 answers
1k views

What is the convergence threshold for ArcGIS Iso Cluster?

The ArcGIS tool Iso Cluster Unsupervised Classification does not seem to have any documentation on the convergence threshold used in the tool. To compare, Erdas Imagine has all of the necessary ...
Aaron's user avatar
  • 51.7k
10 votes
0 answers
713 views

How to use a Spilhaus/ESRI:54099 projection in QGIS

I am trying to make a map using a Spilhaus projection, similar to the one implemented by Esri here. QGIS has ESRI:54099 WGS_1984_Spilhaus_Ocean_Map_in_Square in its list of available projections, ...
Ben's user avatar
  • 405
10 votes
0 answers
480 views

PyQGIS script crashes QGIS 3 when removing a custom pluginLayer which has custom legend

I upgrade a 2.18 plugin to 3.4. PluginLayer has been refactored and I could not create a custom legend as simple as previous major version of QGIS 2 : QgsDefaultPluginLayerLegend was removed. Use ...
Hugo Roussaffa's user avatar
10 votes
0 answers
372 views

Defining partial or complete overlap with QgsSpatialIndex

I'm working on adding some functionality to a QGIS plugin. It currently uses a QgsSpatialIndex to efficiently compute whether the features of a vector layer intersect (potentially millions) of ...
alphabetasoup's user avatar
9 votes
0 answers
125 views

Does QGIS use data source-specific operations?

This may be a very basic question, but I couldn't find an appropriate answer. Does QGIS use data source specific operations where available and appropriate? For example, when using the Join attributes ...
Geotob's user avatar
  • 376
9 votes
1 answer
1k views

GRASS v.clean tool in QGIS gives empty output

I am trying to run v.clean in QGIS 3.10.7. I have a 2D LineString dataset saved in GPKG format and I want to run v.clean to clean up some messy topology. But whenever I run it, I get the same result - ...
wfgeo's user avatar
  • 3,598
9 votes
0 answers
1k views

Nearest neighbour joins for two geodataframes using KDtree from scipy/sklearn

I have a number of large geodataframes and I want to automate the implementation of a Nearest Neighbour function using a KDtree for more efficient processing. The process I want to achieve here is to ...
Jack's user avatar
  • 91
9 votes
0 answers
340 views

Intersections in linestrings using PostGIS

I need to get the intersections of streets and create a graph, so to get the intersections I use this select: SELECT ST_GeometryType(geom), geom FROM ( SELECT a.gid, ST_Intersection(a....
Jessicadomingues's user avatar
9 votes
0 answers
874 views

Change from LineString to MultiLineString when saving layer edits in QGIS

In QGIS, when a user creates a new single part line in an open editing session for a “Multi-Line” SpatiaLite dataset, the QGIS data type is initially a “LineString”. But, when the user commits the ...
Philip Whitten's user avatar
9 votes
2 answers
1k views

commuteDistance in gdistance package in R giving error

I am currently trying to run a function that "calculates the expected random-walk commute time between nodes in a graph. It is defined as the effective distance (resistance distance) between the ...
Vijay Ramesh's user avatar
  • 1,342
8 votes
0 answers
150 views

Exporting Geopackage converts milliseconds of QDateTime to zero

I use this solution to display actual QDateTime value with milliseconds in a temporary memory layer. And I use another solution to export as CSV the value including the millisecond value. But then, I ...
Kadir Şahbaz's user avatar
8 votes
0 answers
1k views

Projection: Mollweide to Equirectangular

I am trying to reproduce in Python a coordinate transformation of a map from Mollweide coordinates (see Figure A) to Equirectangular coordinates (see Figure B) that I saw done in Mathematica in the ...
Loïc Poncin's user avatar
8 votes
0 answers
1k views

Controlling the visibility of a FeatureGroup in Folium with an HTML checkbox

I'm working on a project in Django where I want to show layers on a map by checking or unchecking boxes which I created using bootstrap. I am aware it is possible to use LayerControl to get these ...
Sigo van der Linde's user avatar
8 votes
0 answers
465 views

QGIS contextual menu overriding

I would like to override the default contextual menu in QGIS 3 in the ToC. I've created a class that inherit from QgsLayerTreeViewMenuProvider. from qgis.gui import QgsLayerTreeViewMenuProvider from ...
TrsBar's user avatar
  • 523
8 votes
2 answers
2k views

Adding support to Esri's FileGDB driver when fiona/gdal/osgeo were installed through Anaconda

Is there a way to tweak the fiona/gdal/osgeo packages installed through Anaconda so that they can be used to read/write GDB files using the ESRI FileGDB driver? The main thing I'm actually trying to ...
Felipe D.'s user avatar
  • 2,699
8 votes
0 answers
463 views

OGR failing to unpack polygons and respective holes from shapefile

I'm trying to unpack shapefiles in Python (v3.7.4) using the GDAL-OGR library (v2.3.3). Each shapefile has only one feature containing multiple polygons with holes. They cannot be produced differently....
Thaine Herman Assumpção's user avatar
8 votes
0 answers
2k views

QGIS 3.4 and loading raster from multiple variable NetCDF file

Using QGIS version 3.4.4 when loading a NetCDF file out.nc which contains multiple variables on a fresh Ubuntu 18.04 install I encounter the following error: CRITICAL Invalid Layer : Raster layer ...
paugam's user avatar
  • 161
8 votes
0 answers
1k views

Add private plugin repository to QGIS 3.4

I want to add a repository to my QGIS 3.4 which is on a private server. The repository contains all files needed (plugin.xml and metadata.txt for example) and has the structure as described here: Is ...
Ending's user avatar
  • 555
8 votes
0 answers
2k views

Question marks ("?") in QGIS layer panel when using SVG markers defined with "Data defined override"

When using SVG marker symbols and set the path to SVG file via Data defined override the SVGs display well in the map canvas, but not in the layers panel (applies for QGIS 2.x and 3.x). SVG marker ...
Jochen Schwarze's user avatar
8 votes
0 answers
1k views

Using WFST in Leaflet: can not move/delete features

I write a Leaflet app which makes use of two plugins Leaflet.Draw and Leaflet.WFST. The first allows to create/edit/delete features, the second saves changes to my PostGIS database hosted by GeoServer....
Elena Klimenko's user avatar
8 votes
0 answers
2k views

Getting Spyder IDE to work with QGIS?

I was hoping someone could help me get Spyder working with QGIS. I am finding the python editor limiting within QGIS as I would like to debug my code, use the variable explorer, and be able to run ...
owl7's user avatar
  • 181
8 votes
0 answers
13k views

Creating in-line variable in field calculator of QGIS

I create new field based on other fields. For example; if "Field_A" is smaller than "Field_B", the value of the new field is 'A', otherwise it is 'B'. So I want to create a new ...
Kadir Şahbaz's user avatar
8 votes
0 answers
290 views

Position of vehicles relative to lead vehicle

I have a set of vehicles (think railway) that are in a (semi)fixed formation. I know the lead vehicle and I know the GPS coordinates of the lead vehicle at any given time. Sometimes, I can rely on the ...
kaigoh's user avatar
  • 181
8 votes
0 answers
658 views

GDAL contour line generation at DEM edges

In a Python application I use gdal.ContourGenerate() to generate contour lines (GDAL version 1.11.4 and 2.2.1) from DTED tiles. DTED tiles overlap at the top and the right with neighboring tiles. ...
Detlev's user avatar
  • 4,678
8 votes
0 answers
1k views

Fuller/Dymaxion in proj4/gdal/qgis?

I know this question has been asked a million times already, but I can't find many detailed responses on exactly what I want to do. As far as I can tell, the full C code for the fuller projection is ...
Alex McVittie's user avatar
8 votes
0 answers
215 views

Issues with atlas generator and labelling across maps/images

I have a lot of layers in my project and I am trying to use the atlas generator in the print composer to create a tiled map. Some of the layers have labels which have different configurations with ...
Chau's user avatar
  • 4,490
8 votes
0 answers
583 views

Is it possible to link symbol fill colors between different geometry types in QGIS

I would like to link symbol colors between two layers of different geometry types (point and polygon). I have tried to save/load style and to copy/paste but I don't think its designed to work that way ...
Bill H's user avatar
  • 81
8 votes
0 answers
1k views

Cellular Automata Markov for forecast LULC in R software

I would like to forecast land use changes by implementing the Cellular Automata (CA) Markov Chain models in R software. I have the classified LULC maps from 3 times periods (1992,2003,2014), and also ...
Nery's user avatar
  • 99
8 votes
0 answers
2k views

GDAL RasterIO performance in C++ vs ReadAsArray in python/numpy

I'm currently writing optimisations for a raster viewer program which uses gdal as it's base. It's currently written purely in python, and has some major speed issues which cause problems when we are ...
gjones's user avatar
  • 213
8 votes
0 answers
3k views

Can I use GeoJSON GeometryCollection in QGIS?

I want to create a GeoJSON that contains multiple geometries to be used in QGis later on. Now I red through the specs here: http://geojson.org/geojson-spec.html#geometrycollection When I simply copy ...
Yojimbo's user avatar
  • 393
8 votes
0 answers
654 views

Setting up PyCharm CE 4 to work with PyQGIS library in Mac OS

I am trying to set up PyCharm to work with PyQGIS library. I am using PyCharm CE v4 and QGIS version 2.8 I have tried to implement the instructions of several posts like: http://osgeo-org.1560.x6....
Javier's user avatar
  • 221
8 votes
1 answer
1k views

PostGIS sequence in QGIS not working

I have a Multipolygon-Layer stored in a PostgreSQL/PostGIS database. The primary key field 'gid' is SERIAL. When trying to add a new polygon in QGIS (LYON 2.12.1 on OSX El Capitan), the attributes ...
geom's user avatar
  • 1,296
8 votes
1 answer
4k views

Saving QGIS Project file (*.qgs) with PyQGIS?

I'm having trouble with QGIS (2.18.12) project files on Windows, if saved via Python command. The project file is saved via: project = QgsProject.instance() project.write() The file is saved, I can ...
swad's user avatar
  • 331
7 votes
0 answers
174 views

How to change the Point Cluster circle symbol to a convex hull

I am using the expression presented by the user JGH to solve the question 'Point Clustering in QGIS, but values show a percentage and not count of points' This shows my example: As you can see I use ...
Ingrid Ingravida's user avatar
7 votes
1 answer
386 views

QGIS Model Designer: 'Algorithm is not available' and 'NoneType' object has no attribute 'displayName'

I am building a model to automate a process of generating points at street intersections. When I run the model, there is no output. Checking the error logs, I see this: 2022-04-26T10:55:36 WARNING ...
user200934's user avatar
7 votes
0 answers
250 views

QgsProcessingLayerPostProcessorInterface only processing the last layer

I have a QgsProcessingLayerPostProcessorInterface class as shown below. class LayerPostProcessor(QgsProcessingLayerPostProcessorInterface): instance = None name = "" color1 = ...
ar-siddiqui's user avatar
  • 1,768
7 votes
0 answers
346 views

Increase tolerance of QGIS processing tools

I have 2 line layers in QGIS 3.22.0 and I create a 10cm-buffer around line layer A (red) perform a difference of line layer B (blue) with the buffer of layer A (light red) As a result I get 1 ...
Enzo Baldini's user avatar
  • 2,347
7 votes
0 answers
758 views

Equal Earth Projection in Google Earth Engine

I'm trying to get a gobal visualization similar to what NASA does. They are probably using popular Equal Earth projection (EPSG:8857), but this fails in GEE. In order to implement this projection, I ...
Basile's user avatar
  • 3,583

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