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Questions tagged [qgis-3.0]

For questions about Version 3.0 of QGIS

1
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0answers
14 views

Match a custom CRS to existing (proj4 database) ones in QGIS 3

I am reading SPS files (see format definition here) from which I gather CRS information. Unfortunately, there is no ESPG reference available nor is there any standard naming scheme for Ellipsoids so ...
2
votes
1answer
61 views

How to open and add SQLite connection to browser with PyQgis

I have a code to open the layers of a SQLite database. When executing this code, the layers are loaded correctly (1 & 2). However i also need to connect to the database and show the connection in ...
0
votes
0answers
32 views

How to edit manually file geodatabase's OBJECTID column in QGIS?

I'm using QGIS version 3.4.1 with a Windows 10 OS. I'm trying to edit an Esri FGDB folder. Haven't succeeded. So far so I'm using a workaround: exporting specific layer to a new FGDB - with 'Save ...
0
votes
1answer
21 views

Why can't I load layers from PostGIS db (populated with osm2pgsql) in QGIS?

I have downloaded some OSM data from geofabrik and used this to create a PostgreSQL/PostGIS database using the osm2pgsql tool: osm2pgsql -G -d <db> -U postgres myfile.osm Examining the ...
0
votes
0answers
47 views

QGIS 3 Plugin with cascade list runs slower each time I launch it

I'm writing write a plugin for QGIS. Its first step is to select an item after having selected 'parents items', in a cascade selection. It works, but it is getting slower and slower after a few ...
1
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0answers
33 views

In QGIS, How to add the database connection in DB Manager via Python [closed]

I am using QGIS 3.0.2 I want to add connection settings in DB Manager via Python script. is it possible ? (I am interested in PostGIS and Oracle Spatial for now) This script will save the ...
0
votes
0answers
35 views

Display issues in QGIS Madeira

This is the second time I have tried installing Madeira on a new Dell XPS machine (Madeira works okay on my old Mac although there are some bugs including with changing font sizes in a layout). This ...
1
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1answer
43 views

QGIS 3.4.3 Refactor fields changes symbols in fields (cp1250)

I've been using QGIS Refactor fields to change type, re-order and rename a substantial ammount of columns (statistical data). Most of them hold purely numerical values and are as such not material to ...
2
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0answers
69 views

Unresponsive MessageBar in QGIS 3

I created a little plugin to geocode addresses using the HERE API and QGIS 3. Especially in batch mode, I can see that the plugin is iterating over my features in a table and my messageBar progress ...
0
votes
1answer
30 views

Difficulties working with QGIS 3.4 API

I want to work with QGIS 3.4 in a C++ Qt project, but the API in version 3 has been completely changed and the sample code for older version don't compile anymore. Is there some sample code which ...
1
vote
0answers
37 views

How do you view your Python scripts in the processing toolbox in QGIS 3?

I have been stuck on this for a while and I'm not sure if it is a bug or me doing something wrong but I cannot work out how to add Scripts to the processing toolbox in QGIS 3 series. When I click the ...
1
vote
0answers
21 views

Way of viewing attribute table of layer at end of model without loading layer in QGIS

I have created a model in QGIS 3 graphical modeler, with the final output being a shapefile. I was wondering if it is possible to have the final result as a pop up of the data table just to view the ...
3
votes
1answer
54 views

Using round function in QGIS expression?

I created a grid of rectangular polygons with the Create Grid function, from the Vector Creation group of the Processing Toolbox in QGIS 3.4.2. The rectangles measure half a degree of longitude by ...
2
votes
0answers
38 views

Rendering Google Terrain in QGIS Layout Manager

I am using the Google Terrain map (via XYZ Tiles). This seems to make the system very slow, and when making a .jpeg through the Layout Manager, the Google Terrain will not display (render) when ...
1
vote
0answers
30 views

Read status and XY-coordinates from GPS-widget with Python (QGIS 3)

Is there a way to access the status and the XY-coordinates from a GPS-connection established by the GPS-widget in QGIS 3 via python? I want to establish the connection with the widget to have better ...
0
votes
0answers
106 views

QGIS 3.4 Couldn't load SIP module. Python support will be disabled on Windows 10

I upgraded from QGIS 3.2 to 3.4 and bad things happened. On start-up I get the error. Couldn't load SIP module. Python support will be disabled. Traceback (most recent call last): File "", line 1,...
0
votes
1answer
20 views

QGIS plugin - checkbox un-checked by default

Does anyone know how to set a checkbox to un-checked by default in a QGIS plugin? Is it done within the UI script for the plugin and can it be achieved within Qt Designer?
3
votes
0answers
58 views

How to read PyQGIS documentation? [closed]

As I get more into QGIS scripting, I refer to the documentation often and usually without success. I have trouble deciphering how to interpret the classes, etc. I've been really struggling to create ...
1
vote
0answers
21 views

Saving QML styles directly into QGS project file

I have a QGIS Model (saved in directly in QGIS 3 project file ".qgs") which creates some layers and assign predefined styles to them. I would like to save those QML styles into my .qgs and reference ...
1
vote
2answers
83 views

How to remove legend items with PyQGIS without removing the layer?

I am trying to generate maps in pdf files by using a pre-defined .qgz layout. I am already able to load layers and adjust color scale, etc. Since the legend is synchronized with the map layers, all ...
1
vote
0answers
110 views

GRASS r.slope.aspect via QGIS 2.18 vs QGIS 3.4 - not working

I seem to be unable to replicate actions with GRASS tools when I access them through QGIS 3.4. In particular the r.slope tool. I receive error messages and it fails in QGIS 3.4. They seem to work fine ...
2
votes
1answer
50 views

Progress reporting in QGIS 3.0

I would like to provide the user of a plugin with progress status using messages and a progress bar. My plugin processes several files using memory files, processing, writing to disk etc. It all ...
5
votes
2answers
111 views

QGIS 3 Get coordinates from mouse click

I am working on a small QGIS Python plugin and want to get the X/Y coordinates from a user click on the canvas. I have a small UI called from button in a toolbar. After filling the UI with information ...
3
votes
1answer
55 views

QGIS 3.2: Where are layout files stored?

I am changing computers at work and I want to be able to bring all of my old layouts (the ones accessed through the layout manager) over to my new computer. Each layout is set up on a particular ...
1
vote
0answers
62 views

QGIS 3.4.2 - timemanager plugin - NetCDF - attribute

When updating QGIS from version 2.18 to 3.4.2 my NetCDF files are no longer loading in the timemanager plugin My time variable in the NetCDF file has the following attribute double time(time) ; ...
1
vote
1answer
49 views

Using CLUZ plugin in QGIS 3.4.2?

I wanted to install the plugins CLUZ and Marxan in QGIS, but both do not appear when you search for them in the plugins sections... Does anyone know why this is the case, or how can I use CLUZ then? ...
0
votes
2answers
30 views

How to refresh the HTML, including the linked CSS for a QGIS HTML frame?

I am using a referenced css file in an HTML Frame in a QGIS 3.4.2 layout. <link rel="stylesheet" type="text/css" href="map.css"> It works great until I have to go and edit the css. When I ...
2
votes
1answer
69 views

Compile and load QGIS3 plugin

Win7 x64, QGIS 3.4 installed through OSGeo4W with 'Advanced Install' Here's my workflow: Get the template directory from PluginBuilder3 Navigate to this folder in the OSGeo4W Shell Use call "...
2
votes
0answers
26 views

In QGIS 3 Graphical Modeler can you add a check box to allow for different model path

In the Graphical Modeler in QGIS 3 is it possible to add a check box to the model GUI that if selected takes you down a different path of the tree so to speak. Example: Within a model I want to have ...
1
vote
1answer
45 views

How to find intersection polygons in single layer on QGIS version 3.4.2?

I have polygons intersection in single layer. I want polygon in yellow frame and use polygon intersection to calculate area , how to do this?
1
vote
1answer
26 views

Adding points on a map parcel from an attribute in the attributes table

First, my apologies as I am a newbie and may not be using the correct words or I am asking a question that has already been used. I am using QGIS 3.4.2 and a have a map of a subdivision with roads, ...
1
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1answer
54 views

Join attributes by location - false information

I've been working on an analysis involving animal vehicle collisions. The data has been passed to r-stats and I keep noticing peculiar things in the cross referencing of the data. I've created highway ...
1
vote
1answer
214 views

UBUNTU 16.04, QGIS 3.4 above Installation problem

I want to install QGIS 3.4 above and did exactly the same as this page: QGIS Installers and tried the codes below having no error at all: (1) add the following lines to /etc/apt/sources.list deb ...
0
votes
1answer
62 views

Attribute table not showing data in QGIS 3.2 (prior answers only apply to QGIS 2)

I've opened a .shp in QGIS 3.2.3 and there is no data in the attribute table. It shows the correct number of rows but no columns. A previous answer recommended choosing "Show All Objects" under the "...
1
vote
1answer
51 views

Creating points along line at ellipsoidal distance

I need to create points along a polyline in QGIS 3 at every 1000m of ellipsoidal distance and have tried several tools, as suggested in other answers: Points along geometry QChainage plugin Convert ...
2
votes
1answer
52 views

QGIS3.4 Madeira crashes when calling print()

I am using the pyqgis template from underdark for showing the crash. Her script is running like a charm, but as soon as I add a print("finished...")-call in her code, QGIS3.4 Madeira crashes. You can ...
2
votes
1answer
97 views

Getting line geometry out of two points using QGIS?

I have one input point layer and out of that, I want to create an output LINE vector layer. For each feature in my output line vector layer, I define a geometry which takes 2 point geometries. ...
1
vote
0answers
75 views

QGIS 3 Python plugin psycopg2 Postgres Notify/Listen Live Connection

I'm developing a plugin for QGIS3 for my company, where my managers can allocate tasks to other users. I have programmed two tables within the python script, witch will be only visible according to ...
-1
votes
0answers
30 views

Virtual Fields in PostgreSQL 10.5

I'm having trouble getting a virtual field imported from QGIS 3.0 to PostGIS. The other fields in the layers are importable to my database. We need it in PostGIS to get multiuser-access on the it. The ...
1
vote
1answer
42 views

CAD Editing plugin in QGIS 3.0

Is there a plugin with CAD tools for editing vector entities such as lines and polygons in QGIS 3.0?
0
votes
1answer
77 views

Using v.split in GRASS?

I'm trying to split several lines into bits of a maximum given length using v.split. First, I got this bug: UnicodeDecodeError: 'utf-8' codec can't decode byte 0xe8 in position... which was ...
2
votes
1answer
39 views

Creating VRT or index of large amount of aerial images to create mosaic in QGIS?

I have about 1600 aerial images that I want to create a mosaic of. I tried doing about 400 at a time in a VRT, it's extremely slow (been building polygons for about 15 minutes now + the 20 minutes it ...
3
votes
1answer
88 views

Styles with parameters

I'm using QGIS 3.4 , and without going into python scripting, is there a way I can create some kind of rule based styles where I can add a parameter? I have a number of layers, each with between 1 ...
1
vote
0answers
31 views

Batch processing DTM with Hillshade in QGIS 3

I'm using the Hillshade tool from GDAL library [Raster analysis] in QGIS 3.4. I can't use the batch process with creative options like compress=LZW or profile=Geotif. It doesn't work. The tool works ...
1
vote
2answers
124 views

Output layer from PyQGIS 3 processing script is empty

I've created a processing script in QGIS 3, and although my output layer has shows a feature count greater than zero when using the feedback command, the resulting feature layer that appears in QGIS ...
0
votes
0answers
18 views

How to export a GPX that is ingestable by the ridecommand.polaris.com GPX import?

I am attempting to export a GPX file from a PostgreSQL line table to a GPX file using QGIS and/or OGR. And then upload that to https://ridecommand.polaris.com. For the most part, this seems to be ...
1
vote
0answers
34 views

Failed to load python Qgis 3.4 add-ins

I installed Qgis 3.4 Madeira and it worked fine, but now it throws me two errors The first is the following: The second is: By omitting the two errors that load with several defects, such as: a ...
3
votes
0answers
33 views

How to view layers by data source in QGIS 3?

Is there a tool or panel in QGIS 3 that allows a user to view the map layers by data source? Similar to the List By Source view in the ArcMap Table of Contents? I thought I had come across it, but ...
1
vote
1answer
52 views

Compute 3D seismic fold with QGIS and Python

Computing 3D seismic fold is quite straight forward, for those unfamiliar with the concept, below is a brief explanation. Background information (Seismic 101) : Seismic Fold: Basically, I have (...
1
vote
1answer
488 views

QGIS 3 - Online POSTGRESQL database error “undefined symbol: GEOSFrechetDistanceDensify”

Using QGIS 3 on mac book air and set up a POSTGRESQL database with Acugis 6 days ago. Everything's been working fine and no issues. The yesterday everything went off and was unable to see the layers ...