Questions tagged [qgis-3]
for questions specific to the 3.x series of QGIS.
2,700
questions
0
votes
1answer
31 views
Add Point Features not showing on QGIS 3.1
I have created a shapefile on QGIS 3.1 and have enabled "toggle editing" and need to add point features, but on my qgis platform the add point feature is not available. I have searched for it in the ...
1
vote
1answer
23 views
Fill in areas between lines with polygons?
I have to make a geographical map.
I have to fill in the gaps between the lines with polygons. Is there a possibility to just trace those lines automatically?
I have to do everything manually now, ...
0
votes
0answers
13 views
Finding name() in Script Batchprocess - QGIS 3.4.7
I created a script to run in the toolbox from a model that runs perfectly except if running as a batch process.
The script refactors the input file and create the Name column based on the file's name ...
0
votes
0answers
14 views
QGIS Server Installation Issue - Ubuntu/Debian
I'm trying to install QGIS Serveur on Ubuntu.
I have followed this tutorial but it is not complet :
https://docs.qgis.org/3.10/en/docs/user_manual/working_with_ogc/server/getting_started.html#nginx
I'...
1
vote
0answers
21 views
Creating polyline segments on points on maximum distance to each other along another polyline using QGIS
I have
a polyline layer contains different roads
a point layer contains points along these roads with random distances between the points. The points are also listed randomly and not in order along ...
0
votes
0answers
30 views
Getting layer name of processing step in QGIS graphical modeler for usage withing aggregate() function
How can I get the layer name or layer id of an processing algorithm within QGIS graphical modeler, so I can use aggregate() function in a later processing step and fetch the geometry of the previous ...
0
votes
0answers
16 views
Plotting individual data points to accurately show area
I'm relatively new to QGIS and am running into difficulty creating a map for work. I need to plot two separate data points which represent an area of 2 metres squared each (shown on the map as ...
0
votes
1answer
12 views
QGIS -> MySQL Updates
I added a MySQL layer containing GeoData to my QGIS 3 project.
I want this layer updated every time the database updates.
Is there a way to do that?
1
vote
1answer
22 views
Adding Visibility Analysis algorithms to standalone QGIS script
I'm writing a script to compute the intervisibility between two sets of points using the Intervisibility algorithm from the Visibility Analysis plugin which (to my knowledge) is installed by default ...
2
votes
1answer
32 views
QGIS modeler: using input rasters filename for naming columns by expression
I am running QGIS 3.12.3 București on Windows 10 x64; I am building a simple model to reclassify a series of rasters with a 2x3 table, and then count each unique reclassified value within different ...
2
votes
0answers
17 views
Marking distances with QChainage Tool and Marker Lines (they differ)
I have an issue with the markers created by the QChainage Tool and Marker Lines created in Layer Properties (under Symbology). I was trying to use the Marker Lines to create unlabeled intervals ...
0
votes
0answers
28 views
Disable mouse wheel zoom in QGIS 3.12.3-Bucuresti [duplicate]
I'd like to disable using the mouse wheel to zoom. I have an Apple Magic Mouse and it's way too easy to accidentally scroll/zoom while trying to do other things. It looks like this option has come and ...
1
vote
1answer
35 views
Progress bar does not show progress during processing
I am trying to show the progress in the progress bar, but it is not running, I have seen several solutions but none has solved me.
This is part of the code that I am using :
def progress_changed(...
3
votes
1answer
56 views
Finding closest points on another polygon
I have three layers:
polygons (having an unique id)
stops (having the polygon id it is laying on) (point)
possibilites (having the polygon id it is laying on) (point)
I now want to find the closest ...
1
vote
1answer
43 views
Filtering a value relation selection box with an expresion when one column has string LIKE the other Column
Oke I have setup two value relations between one polygon layer and two tables, this is to make the selection of multiple values possible. The first value relation is not really that important you just ...
1
vote
1answer
53 views
Dissolve a table with no geometry QGIS return Null if any are Null
I have a table without geometry that contains three columns: Item, Sub-item, and amount. I would like to create a new table with the sum of the amount of the sub-items that have the same Item ...
1
vote
0answers
32 views
Sum area of features intersecting atlas feature in QGIS
I have AOI layer named "Clusters" which is set as the Atlas coverage layer for my project
I want to sum the area(Hectares) of specific intersecting features from my "...
0
votes
0answers
22 views
How to build a QGIS-3.10 script without an output layer?
So I've read about the processing scripts you can do in QGIS 3. However, there seems to be no way of just modifying a layer directly and instead I have to have an output layer, which I do not want.
...
2
votes
1answer
32 views
QField - Managing photo storage
I'm using QField and was able to setup almost everything.
I managed to enable photos creating a table (with the "attachment" type, relative path and so forth) and building relations to my Shapefile. ...
4
votes
1answer
64 views
PyQGIS count points in polygon grouping by attribute
I have a point layer with an attribute table like this:
id_point class
1 A
2 B
3 A
4 C
5 B
...
What I need is to count how many points of ...
1
vote
0answers
38 views
Removing rectangle line in DEM
enter image description hereI have downloaded Aster dem file. One of my dem file has rectangle line.
Does any body know how to remove it? I am using QGIS 3.4.
-3
votes
0answers
24 views
Create a raster with the maximum value of two rasters for each pixel? [duplicate]
I need to create a raster with the maximum of temperature register between each pixel of two rasters.
3
votes
1answer
72 views
Feature index for atlas
I am working on an atlas project in qgis 3 that is basically roads, towns, and other features for a quite large area. What I would like to add, is an index of all the towns in the atlas area with at ...
0
votes
1answer
34 views
QGIS 3: equivalent tool/plugin of ArcMap's Spatial Join within a Distance
I would like to do a join by location between two point layers in QGIS 3 (3.4.10, Coruña). I would like to get the mean (or median) value of an attribute all the points of point layer 2 within a 5 ...
2
votes
0answers
19 views
Select overlapping features from single layer
in QGIS 3.10 LTR we have the opportunity to identify vector features with the mode "Top down".
Is there a way to do this with the "Select features"? We'd like to select all overlapping features when ...
1
vote
2answers
18 views
Save an image from the project
I took a tif file and cropped it to a portion using Raster>Extraxtion>Clip Raster by Extent. My project name is OBIA. After cropping the image is saved to this project. How do I download this image?
0
votes
1answer
29 views
QGIS 3 Python support disabled Linux
Couldn't find a similar question for Linux, just Windows.
I'm running Linux Mint 19.3.
Traceback (most recent call last):
File "", line 1, in
File "/usr/lib/python3/dist-packages/qgis/__init__....
0
votes
0answers
15 views
Error in pasting copied features in QGIS 3.4.5 Cannot create field
I have a dxf layer from which I want to copy the lines into a new shapefile layer. I have selected the lines and managed to copy them successfully. However, when I try to paste the lines through Edit--...
0
votes
0answers
33 views
QGIS 3.10/3.12 on Linux cannot interpret ZStd TIFF Compression
I have installed QGIS 3.12.X (and also QGIS 3.10.X) under Linux Ubuntu and Linux CentOS, but when trying to open ZStd encoded TIFF Files, I get the error message:
[file path] is not a supported ...
1
vote
2answers
29 views
Adjust multiple text items in composer
In composer I can select multiple items but if I change their attributes the change is only applied to the first item selected.
Example:
Select multiple text items using shift select (Mac OS X), ...
1
vote
1answer
17 views
Convert a polygon geopackage into a multi-polygon geopackage in QGIS
I have a series of polygons in a geopackage file of QGIS polygons. Is it possible to transfer the contents of this file to another geopackage that has multipolygons as vector data type?
I need to fix ...
1
vote
0answers
20 views
I cannot use Point entry into Graphical Modeler in QGIS
I would like to use a Point entry to get the point coordinates in the map to add in the network analysis as a start point.
I have added the Point entry into Graphical Modeler, I can click on the map ...
1
vote
1answer
20 views
Limiting map tips popups by scale in QGIS?
I have a points later and have enabled map tips to appear when I hover, as normal. However, I would like to prevent map tips balloons from appearing when zoomed out. The way I have found to accomplish ...
5
votes
1answer
46 views
Use tracing when extending linestrings in QGIS
In QGIS 3 it is possible to extend an existing linestring by clicking on the 'virtual endpoint' cross marker as described in https://docs.qgis.org/3.10/de/docs/user_manual/working_with_vector/...
2
votes
1answer
46 views
Removing segment from circle?
I have drawn a vector circle with "Add circle from 2 points".
How do I remove a segment of this circle? In essence, I want to edit a circle and convert it into an arc.
0
votes
0answers
13 views
Spatialite layer with multiple geometry type in QGIS3
The spatialite table has field with GEOMETRY type and contains both line and polygon features.
How to add them in QGIS 3.8.1 project as individual editable layers?
2
votes
1answer
44 views
Vector grid id generation [duplicate]
I generated a grid with 300m spacing but the ids generated from top to bottom in sequential oder. How could I get in horizontal from left to right sequence.
1
vote
1answer
77 views
Find the altitude of a point
I have a polygon layer and I want to know the altitude of the centroids. I guess I have to find on the internet (how?) a layer that contains data about the territory's height (in this case Italy in ...
1
vote
1answer
40 views
Moving between pages in QGIS Print Composer
I'm using QGIS 3.6 Print Composer, and I managed to create a layout with two pages.
I now want to delete page 1. How do I move from page 2 to page 1 so I can delete it?
0
votes
0answers
26 views
Save processing modeler output layers to project folder/relative path?
I am building an algorithm in the processing modeler which takes a csv file as input and creates a number of vector layers as output. I would like to automatically save these layers in the same folder ...
1
vote
0answers
28 views
QGIS error while opening properties programmatically of added layer [closed]
QGIS crashes when I try open properties of programmatically added vector layer, but when I save project and reload everything is ok. I use QGIS 3.10, but I tried also on 3.12. Only QGIS on Linux ...
0
votes
0answers
16 views
How to show the data of snapped features created on QGIS 3 in hierarchical tree form using python?
I have created layers for polygon,line and point.
Once i have snapped line and point on map i want to see information in a tree like format in QGIS3 using python.
I am new to QGIS please help me how ...
0
votes
0answers
14 views
install lates version of qgis - Errors were encountered while processing
By following the installation's guide, ireceive this error after typing sudo apt-get install qgis qgis-plugin-grass.
The error is :
Setting up oracle-java11-installer-local (11.0.7-1~...
0
votes
0answers
34 views
How do I save file to .shp with have many attribute? [duplicate]
Is there a way to save a file to .shp with have many attribute (I use QuickOSM to create a building Layer and I tried to save but it get error) and Is there a way to change .KML to .shp ?
I get ...
1
vote
0answers
27 views
GeomorphicFloodArea Plugin is not working
I'm trying to get the plugin GeomorphicFloodArea to work but cannot.
I tried using QGIS 3.10 but got an error message, so I downloaded version 2.18.28 and it still will not work. I get an error ...
2
votes
1answer
48 views
How to select specific fields using getFeatures() without getting all of them in QGIS-3.10
So I'm trying to convert code from ArcGIS to QGIS. The part I am at right now is converting:
lst_fields = ["full_id", "osm_id", "osm_type", "boundary", "is_in", "leisure", "name", "type", "landuse"]
...
1
vote
0answers
39 views
Map output with multiple “Zoom Levels” in QGIS 3 [duplicate]
Just wondered if it is possible to do BBC-style multiple "Zoom Levels" output in QGIS 3 like this:
I used to use another app such as Adobe Illustrator to overlay the maps of different scales. ...
1
vote
1answer
16 views
SAGA Point Statistics for Polygons
I am running QGIS 3.10 on a MAC using Catalina (and I also tried on QGIS 3.4) and tried to run SAGA Point Statistics for Polygons. Every time I run it I get an error with it trying to create the layer....
0
votes
0answers
65 views
Selection on PostGIS layers is… randomly working in QGIS
Context
Quick question...
Since the last minor update of QGIS 3, I cannot select features anymore on some (not all) PostGIS layers (see Fig.1).
Fig.1: On the left table, the selection is not ...
0
votes
0answers
40 views
Adding shapefile layer in PostGis creates two tables
When I try to upload a shapefile to my PostGIS database, it creates two tables (I can see them in QGIS). I import them by drag and dropping them on the PostGIS connection.
If I delete one of them, ...
