All Questions
7,900 questions
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13
views
Export DXF using PyQGIS and change layer order
When I use project > Import/ Export > Export project to DXF my hatches come out below my other content as desired in the resulting DXF.
When I use the code below the hatches come out on top, ...
- 2,002
1
vote
1
answer
27
views
TypeError when exporting point cloud layer to drive with QgsPointCloudLayerExporter.doExport() via PyQGIS
I am trying to save some point cloud layers to disk without benefiting from the GUI export (that is to say using PyQGIS commands).
The point cloud layers are results of earlier filtering that I ...
0
votes
0
answers
24
views
How to reduce load on calculations in PyQGIS
I am trying to calculate the length of a network with creating length field and giving it expression of '$length'. I have approximately 3000 features in layer. I tried two ways
By giving default ...
- 13
0
votes
0
answers
11
views
Control rendering order in processing plugin doesn't work
I want to set rendering order for my layer Layer name by time field in descending order. When the layer is loaded in the project, I run the code below in the console and it works fine. But when I put ...
0
votes
1
answer
39
views
QGIS python configuration LayoutTable
I have a problem when I import layout template in QGIS project with Layout Attribute Table. In template I have two frames (tabela1 and tabela2) for one table which is connect to layer "VOZLISCA&...
- 1
1
vote
0
answers
28
views
Pasting code in python console in QGIS, recognize line change
I'm trying to simply paste Python code I have in a text file to the QGIS Python console.
While this worked before, I'm now receiving this error:
SyntaxError: multiple statements found while compiling ...
- 587
2
votes
1
answer
35
views
Getting Georeferencer target CRS with PyQGIS [closed]
According to the C++ code in qgsgeorefmainwindow.cpp I tried to retrieve the Georeferencer target CRS with PyQGIS using QgsSettings().value("/Plugin-GeoReferencer/targetsrs") but ...
- 6,417
0
votes
0
answers
24
views
Why does layer.materialize() fail to copy features in gpkg files containing json data?
After making this post: layer.materialize() function not copying all features within layer
I ran another multi-part test to determine why layer.materialize() does not copy all features within ...
- 33
1
vote
0
answers
44
views
layer.materialize() function not copying all features within layer
What could cause the layer.materialize() function to not copy all the features within a layer?
Similar Post:
layer.materialize() does not copy all features
Steps to reproduce:
Drag an s57 file in ...
- 33
2
votes
2
answers
154
views
Using PyQGIS to get data contained in the "in-memory editing buffer" of layer that is currently being edited
I am writing a Python plugin for QGIS and I need to be able to retrieve data about the current edits to a particular layer with in QGIS before the edits have been applied.
There does not seem to be ...
- 33
1
vote
1
answer
74
views
Run standalone PyQGIS script with processing algorithms from external plugins
Some of the external QGIS plugins contain processing algorithms integrated by the processing toolbox after installation, e.g. the plugin "Shape Tools".
How can the processing algorithms from ...
- 607
0
votes
0
answers
79
views
Applying also the labels, assigning a .qml style file to a layer with PyQGIS
I'm working on QGIS 3.36 and I'd like to apply a .qml style file to a layer. Writing the following instructions of my code, the aspect of layer changes as I want it, but it doesn't load the labels ...
1
vote
1
answer
55
views
Setting precision for decimal values when labeling layer with PyQGIS
I am currently working on a project in which I need to turn on the "RESULT_PRE" field label so this is the code but the field holds decimal values and I want to give a precision of 3 digits. ...
- 13
1
vote
0
answers
22
views
QGIS Server missing DB Manager providers on Docker/Debian
i´m triying to create a QGIS Server container on Docker, following the example in documentation: docs. The purpose of this container is to export some layers from a .gdb file to an external PostGIS ...
- 11
2
votes
0
answers
45
views
"IndexError: list index out of range" error when reading memory layer with PyQGIS
In QGIS 3.22.10, I created a No Geometry layer and a group layer. The No Geometry layer was added to the group layer, and it was added perfectly. I can see the data in QGIS.
Here is the code for layer ...
- 1,225
1
vote
0
answers
47
views
"ImportError: attempted relative import with no known parent package" error when running QGIS Plugin in PyCharm
I am trying to run a Plugin that I created in the Python debugger and it gives this error:
ImportError: attempted relative import with no known parent package
Which appears to be related to this ...
- 363
1
vote
0
answers
34
views
"No module named PyQt5.sip" error when using PyQGIS in standalone script
I tried to run Python code from PyQGIS Developer Cookbook | Using PyQGIS in standalone scripts
on Windows 10, but I got an error:
I installed PyQt5 and PyQt5-sip, and set all paths but the error ...
- 43
0
votes
1
answer
38
views
Georeferenced images from a grid
I have a layer with the attributes height, width, x, y, vertex_ind and a path pointing to a non-georeferenced jpg image.
I know how to use the x,y coordinates of each vertex to translate the angles of ...
- 1,015
2
votes
1
answer
71
views
QGIS plugin showing multiple messages in the message bar
I am adding some user feedback to a plugin.
I have followed the pyqgis developer cookbook to create a message as below.
self.iface.messageBar().clearWidgets()
messagelinktext = 'something is happening'...
- 2,002
1
vote
1
answer
68
views
Add in content of text file in algorithm dialog in Processing tools text box
I am learning how to create my own processing toolbox, I just want to be able to select a text file and display the content in the multiline text box. I can put "some text" in it but not the ...
- 3,349
1
vote
0
answers
41
views
"Cannot import http://spatialreference.org/ref/epsg/3812/ due to ALLOW_NETWORK_ACCESS=NO" error in PyQGIS
I am building a headless PyQGIS application that will need to be integrated into a bigger system.
Everything works, but when reading a layer from a GML file, the output keeps printing:
Cannot import ...
- 1,367
2
votes
1
answer
65
views
Running PyQGIS processing algorithms within FME PythonCaller
Using FME Form 2024.1.2 and QGIS 3.34.4 with Python 3.9 the following script:
import fme
import fmeobjects
import sys
from qgis.core import QgsApplication, QgsVectorLayer, QgsProcessingFeedback
...
- 607
3
votes
1
answer
110
views
Aligning rasters using native:alignrasters with PyQGIS [closed]
I would like to use native:alignrasters to, obviously, align two rasters. However, it does not accept my input layer, despite it being valid.
(I tried native:alignsingleraster as well, but that is ...
- 69
2
votes
1
answer
79
views
Pole of inaccessibility and buffer loop using PyQGIS
I'm trying to create a Python script in QGIS that will identify potential sites for tree planting in residential areas.
The logic is:
Start with a layer "trn_fts_roadtrackorpath" that ...
- 41
1
vote
2
answers
77
views
Setting max zoom level of QgsRasterLayer with PyQGIS
I'm using PyQGIS to add QgsRasterLayer layers to my project.
This is how I create the layer:
urlWithParams = "type=xyz&url=http://ecn.t3.tiles.virtualearth.net/tiles/a%7Bq%7D.jpeg?g=1"
...
- 113
0
votes
1
answer
90
views
Trouble getting SAGA to work in QGIS 3.4 for Mac
I have been trying to get the SAGA toolbox to work in QGIS 3.4 but it does not show up. I have downloaded the SAGA Next Gen plugin for QGIS, and I have also downloaded SAGA from SourceForge and set ...
- 345
-1
votes
1
answer
91
views
Symbolizing QGIS Raster with PyQGIS [closed]
I would like to symbolize raster layers using PyQGIS.
If I understand correctly using a prepared style-file is no solution, since the maximum value of the raster changes depending on the inputs of it'...
- 69
0
votes
1
answer
63
views
Setting color of feature of polygon layer with PyQGIS
I'm working on QGIS v. 3.36, I'd like change the color of a feature of a polygon layer called "canvas", but creating QgsMarkerSymbol and setting the renderer, the symbol on the map is ...
2
votes
0
answers
39
views
Changing the data source of QgsVectorLayer with PyQGIS
I am trying to update the data sources of all the layers of a project. I am going from a SQLite source to a PostgreSQL db source. I can't delete and re-add the layers because there is a large number ...
0
votes
1
answer
42
views
How to add a WMS layer to QGIS using PyQGIS with custom authentication headers [closed]
I’m working on adding a WMS layer to QGIS using PyQGIS, and while it works perfectly without authentication, I’m having trouble when custom authentication headers are required.
Here are the scenarios ...
0
votes
0
answers
31
views
SAGA in QGIS 3.30 and versions above
I created a plugin that needs to create a drainage area from an outlet point, for this, I was using the SAGA "upslope area" tool, but I realized just now that I was using SAGA Next Gen in ...
- 99
0
votes
0
answers
30
views
Conflct between QgsMapTool and QgsMapToolDigitizeFeature
I created a plugin with one QgsMapTool and one mapTooldigitilizedFeature. When I use the QgsMapTool before the mapTooldigitilizedFeature, I can't digitize my feature and my QGIS crashes.
self....
0
votes
0
answers
62
views
Dealing with QGIS freezing when executing PyQGIS script
I want to create a tool that allows me to use a source layer to retrieve the parcels contained in the selected commune from my PostgreSQL database.
When I use layer actions, everything works fine. But ...
0
votes
0
answers
24
views
Legend Cropped on First Export Using PyQGIS - Why Does It Render Correctly on the Second Export?
My function below creates a map in my processing toolbox. I am having a problem with the legend.
def create_geology_overview_map(project, vlyr_ezgStats, ezg_qml, vlyr_geol, geologische_layer_qml,
...
- 1,606
0
votes
0
answers
23
views
After use commitChanges in layer PyQGIS generate ERROR Failed to delete file qix
When I use commitChanges on a layer in PyQGIS then it generates ERROR 1: Failed to delete somefile.qix
I use it in the button method when I want to save the edit changes in the layer. Here is the code:...
- 49
1
vote
2
answers
65
views
Download location plan centered on each point with QGIS
I'm trying to download the location plan for each point on my network. This will allow me to fill in a data sheet with a GIS photo with the manhole in the center.
I've managed to find out how to ...
- 11
2
votes
1
answer
67
views
Sorting Recently Used Coordinate Reference Systems list in QGIS
I want to sort alphabetically all CRSs in the Recently Used Coordinate Reference Systems list in QGIS. But I can't find a way to do this using the user interface.
How one can sort them using PyQGIS?
- 8,208
3
votes
0
answers
62
views
Custom rotate function based on spheroid
Basically if PostGIS had an ST_Rotate but for geography type where it calculated based on a spheroid. But in my case I want to do this in a QGIS plugin. I need to rotate polygons and I only ever need ...
- 616
0
votes
0
answers
79
views
Making vertex edits on polygon layers using PyQGIS
I've got a bug/problem in my PyQt QGIS based app.
CODE SNIPPET DOWN BELOW
A little context first:
The app enables users to load polygon data into different map layers which I display on the QGIS map. ...
- 1
0
votes
1
answer
68
views
Cycling thru themes and and using composer with PyQGIS
I'm trying to make QGIS go through a few themes and export the map with the Composer but I don't manage to switch theme.
I tried to get some help from ChatGPT and I few snippets I found on GitHub, ...
- 149
1
vote
1
answer
86
views
Creating temporal raster (timeseries) in PyQGIS
QGIS can animate a temporal raster using the Temporal Controller. I am trying to programmatically create a layer in Python that can be animated in this way.
What I can do so far is to create a numpy ...
- 13
-1
votes
1
answer
51
views
How to retrieve values from the layer property window via a script? [closed]
I can obtain via the property window the values: Upper Left / Lower Left / Upper Right / Lower Right for a non-georeferenced image.
How can we obtain these values via a script for several hundred ...
- 1,015
0
votes
0
answers
36
views
Cost raster does not start with zero
I used processing.run('grass7:r.cost', params) to create a cost raster starting at one or several points along a street-raster-layer. Each cell is 1m² and the algorithm is supposed to accumulate (...
- 69
0
votes
0
answers
28
views
Failure to load qgis_core.dll in py scripy
We (Git Hub's co-pilot and I) are attempting to automate several processes using Python. One step in the process requires that I create and manipulate QGIS projects. Apparently this step requires ...
- 1
2
votes
1
answer
68
views
Button to update the categorized renderer of layers in QGIS
In QGIS the empty layer "Symbology" has a categorized renderer that defines a color for each country. I want it to act as a global categorized renderer for several hundreds of layers and so ...
- 23
0
votes
1
answer
67
views
Large in-memory raster calculations in PyQGIS
My workflow in a nutshell: I create cost rasters from starting points along a street network (grass7:r.cost), reclassify them according to their distance values (gdal:rastercalculator) and would like ...
- 69
1
vote
1
answer
54
views
Custom Python Script Runs Automatically in QGIS Startup Instead of Appearing in Processing Toolbox
I'm working with QGIS 3.34.11-Prizren and have a Python script that I want to use within the Processing Toolbox. My goal is to incorporate it into a model in the Model Designer. However, I am facing ...
- 101
1
vote
2
answers
70
views
Completely removing layer from QGIS (to delete it)
I have this code below which works well, creating an intersection layer.
But if it works the first time, at the second time it blocks, because the intersection layer is locked by QGIS (but I remove it ...
- 21
0
votes
1
answer
31
views
Migrate projects and information from QGIS 2.x to QGIS 3.x [closed]
How can I migrate projects and information from QGIS 2.x to QGIS 3.x?
I can't find much documentation about it, it is from the QGIS version 2.18 to the current 3.34
What things must be taken into ...
0
votes
1
answer
44
views
QGIS Set Project Colors via Python
since we try to automate QGIS related project settings, I am currently struggling with setting project colors in the project properties usinq PyQGIS.
I managed to retrieve any existing color scheme:
...
