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Spatial data processing framework that brings advanced analysis capabilities to QGIS.

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1answer
35 views

Distance Matrix with 2 point shapefiles and one street network

I have two point shapefiles (start/destination) and one sort of street network shapefile. I would like a to create a distance matrix from the start-shapefile to the destination points, using the ...
1
vote
1answer
41 views

Error: Algorithm not found with correct processing use

I try to run a simple dissolve algorithm in a standalone Python 3 script. My code is following : from qgis.core import QgsVectorLayer import processing from processing.core.Processing import ...
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votes
0answers
10 views

Changing name of outputlayer dynamically in QGIS Processing script?

I have a processing script to load txt-data from a magnetometer and convert them into a vectorlayer (to make a raster in a second step). I want the name of output layer to be changed into something ...
0
votes
2answers
31 views

Statistics on grid cells over GRID format file layer

I have state wide data here that I would like to overlay a grid layer of 1kmx 1km onto. I used the processing toolbox in QGIS 3 (Create Grid) in order to create a grid layer of 1km x 1km lines under ...
1
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0answers
17 views

QGIS Processing v.net.distance Error

I am hoping that someone can point me in the right direction. I am wanting to calculate the distances from a point to each point in another layer along a road network using v.net.distance. I have done ...
0
votes
0answers
21 views

Create axes given origin and angle [closed]

I have a QgsPoint. One of the attributes of this point is 'heading', a number from 0 to 359 indicating an angle. I want to create two lines going though this point, one in the direction of this ...
0
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0answers
15 views

Altered Minimum Bounding Box Algorithm [duplicate]

I'm trying to create an algorithm similar to minimum bounding box (though it may end up looking nothing like it). In this case the angle will be passed as a parameter and given the angle I need the ...
1
vote
1answer
32 views

Correct way to delete a field, add a field and update attributes in pyqgis

I am working on a script that runs a model and then appends the result to a spatialite layer. The model runs zonal statistics using 4 different rasters and appends them to the attribute table of a ...
1
vote
2answers
61 views

Processing toolbox nowhere to be found

I have just downloaded the newest version of QGIS (3.2) and the processing toolbox is nowhere to be found. It says that it is now apart of the core package, but i cannot find it on anywhere on the ...
2
votes
1answer
26 views

How to call “Clip Raster by Mask Layer” tool using QGIS console? (gdal:cliprasterbymasklayer)

I execute the followng code in QGIS 3.2.1 console, but Clip Raster by Mask Layer tool doesn't work - output file is not created. Here is QGIS console output: None # perhaps this None appears as a ...
1
vote
0answers
16 views

semi automatic plugin v value in automatic threshold calculation

what does the 'v' defined value stands for in automatic threshold calculation in semi automatic plugin in QGIS
0
votes
1answer
28 views

QGIS 3.2.0 on Mac Sierra 10.12.6 not loading Processing / Vector / other toolbars

I've already changed the Environment to enable "Use Custom Variables" and added a "Prepend" "PATH" ""/Library/Frameworks/GDAL.framework/Programs:/Library/Frameworks/Python.framework/Versions/3.6/bin:""...
1
vote
1answer
24 views

Getting count of overlapping portion of different line features within one shapefile using QGIS?

I have a line shapefile that has overlapping on certain portion of the line features. I need to know the count of where these overlapping occurs and if there is no overlap to keep it as Null or 0 as ...
0
votes
1answer
21 views

Adding LWGEOM to QGIS 3 Processing Toolbox

In 2.x versions of QGIS I was able to add LWGEOM to the QGIS Processing Toolbox and run the Make Valid command. Using OSGEO4W, I've downloaded QGIS 3.2.1 and also downloaded the latest LIBLWGEOM, but ...
1
vote
0answers
15 views

Selecting pixels in raster using polygon selection tool in QGIS?

I want to reclassify landcover image manually with respect to online imagery. I am looking for a software/plugin/script to manually select raster pixels using polygon selection tool and could be able ...
-1
votes
0answers
40 views

How to change shapefile datatypes in R [closed]

I have a shapefile I'm working on with about 200+ columns. The dataset has the regular object ID, length, but also a unique identifier for each row. The columns I am working on are for different ...
1
vote
2answers
27 views

QGIS - Layer style categorizing insert missing values

In QGIS Bonn, when styling my layer to use the categorize option, I want to have all values within a range, for instance, 0 to 50000. I am using the data from a CSV that has information about ...
1
vote
0answers
33 views

Programatically checking if field is empty in QGIS?

As part of a complex workflow which will involve several models in QGIS 3.2, I would like to check if all features in a layer resulting from a model's output do not have an empty value on a specific ...
3
votes
1answer
160 views

Ignoring invalid input features with Intersection tool in QGIS?

In QGIS 2.18, when I used the Vector > Geoprocessing Tools > Intersection tool, I was able to check an option which said "Ignore NULL geometries [optional]". Now I've downloaded QGIS 3.2 and that ...
0
votes
1answer
63 views

How to output multiple raster in QGIS processing scripts

I am writing a script in R for running in QGIS processing. The code is a oil spill classification algorithm and depending on the number of polygons which user inputs in the shapefile, output raster ...
2
votes
1answer
31 views

How to input an array in R script running inside QGIS

I am using QGIS 2.18.21 and running an R script which needs various files as inputs. The number of files to be inputted is also entered by user. I am thinking of taking the input of all file paths in ...
1
vote
0answers
50 views

v.rectify don't work properly from processing toolbox in QGIS 3.2

I would like to use the tool "v.rectify" from GRASS in my plugin, but when I call it, it continues to say that "ERROR: Required parameter 'output' not set", although this parameter is set. I think ...
3
votes
0answers
30 views

How to create tests for QGIS' processing models

Short version: Is there a way to create automated tests inside my own processing models? Extended version: I am just starting with QGIS' processing to create some complex model which makes quite a ...
0
votes
1answer
67 views

Using processing algorithm 'native:hublines' in standalone QGIS application

I am trying to make hub lines between two vector files. I succeed manually to do that (in QGIS 3.0) and in a PyQGIS 2.18. But my code doesn't work in PyQGIS 3.0. Here it is: output = '/home/user/...
1
vote
1answer
75 views

Where to find documentation on algorithm parameters when writing scripts in QGIS 3?

For older versions of QGIS, the algorithm parameters were documented in the 'Console usage' section in the QGIS documentation (e.g. the reproject layer documentation). In the QGIS 3 documentation (e.g....
0
votes
0answers
39 views

R Regression Line to Localized Regions

I am attempting to compute a regression line from two rasters in QGIS, using the R statistical package r.regression.line. Raster 1 is a temperature dataset, which is as follows: Raster 2 is an ...
1
vote
1answer
70 views

Input string value in QGIS 3 Processing Scripts

I am trying to port my old QGIS 2.x processing scripts to QGIS 3.x. One of my scripts just needs two variables to initiate several processes to set-up a working environment in my QGIS map document (...
1
vote
0answers
28 views

Unable to update R scripts in Processing

I'm unable to update my R script on Processing. Nothing happens after hit OK button. Those scripts under "Updatable" never get updated. Am I missing something? (QGIS 2.18.21, Linux Mint 18.3 ...
2
votes
1answer
44 views

Empty results using R scripts in QGIS

Using QGIS, after run R script like Histogram it returns an empty result in "Results Viewer" window and no image are created inside html file. Any ideia of missing configuration or package install? ...
3
votes
0answers
21 views

How to use the output of one run as input to the next in QGIS batch processing?

I'm trying to do a series of buffers using the processing batch interface, and I want to use the output of the first run as the input to the second (and so on). But I can only pick an existing file or ...
2
votes
1answer
60 views

Ordered weighted averaging error: can only concatenate list (not “str”) to list

I am trying to perform an ordered weighted average on two rasters in QGIS 3.0.3 (as a trial run for doing it on more than two rasters). But I keep receiving the following error code: Traceback (most ...
3
votes
1answer
46 views

How to create a boundary around transmission lines?

New to QGIS and GIS in general. I'm using QGIS 2.18 and I've downloaded the shapefile from here https://hifld-geoplatform.opendata.arcgis.com/datasets/electric-power-transmission-lines. I set up a ...
0
votes
0answers
40 views

Processing error: “NoneType' object has no attribute 'getitem'” [duplicate]

I am using windows 7, QGIS version 2.18.19. I tried the following standalone python script. ##Testing=name drawingdxf=file cleanf=output vector outputs_GRASS7V_IN_DXF_1=processing.runalg('grass7:v....
2
votes
3answers
284 views

Why does QGIS 3.2 “native:extractvertices” algorithm not work properly in standalone script?

I execute standalone python code (almost identical to the code in the accepted answer): The output file does not contain data, and I get this error message: Warning 6: Normalized/laundered field ...
1
vote
0answers
31 views

GeoPandas causing issues with PyQGIS standalone

I have a code where I would like to be able to use both GeoPandas and PyQGIS. However, it seems that including GeoPandas is causing issues in the output of PyQGIS. Here is a small illustration using ...
0
votes
0answers
36 views

Remove overlaps by moving overlapping features with a specific, scale-based delta

I need to use QGIS to move multiple polylines for tracking data. I want to move any overlapping feature to the left or right with a specific delta based on a scale. I can do that with ArcMap using ...
1
vote
1answer
65 views

How to set the “LAYERS” parameter of the QGIS 3 algorithm “native:mergevectorlayers”

I do not understand how to set the LAYERS parameter for the QGIS 3 native: mergevectorlayers algorithm (for standalone python code). Merge vector layers (native:mergevectorlayers) ... ----------------...
1
vote
0answers
42 views

Metadata Updating in QGIS?

I am working in QGIS. Is there a way you can lock the metadata so that no one can edit or change anything except me?
2
votes
0answers
57 views

User friendly list of processing algorithms in the QGIS 3 python console [duplicate]

The QGIS user guide section Using processing algorithms from the console has not yet been updated for QGIS 3 and while a previously answered question will do the trick with some extra work, it is not ...
0
votes
0answers
31 views

Unable to use QGIS 3 algorithm `qgis:mergeshapeslayers` in standalone code [duplicate]

I use QGIS 3.0.2, Windows 7, OSGeo4W64 to combine the shape files in the stand-alone code, but the output file is not created and the error message does not appear. Calling help information about ...
1
vote
0answers
36 views

'Select by Location' algorithm using Python script in QGIS

Could anyone explain to me how to run the 'select by location' algorithm in a QGIS 3.0 script? I find it really hard to understand the documentation about it. I found a lot of docs about how to write ...
1
vote
0answers
27 views

Changing parameter values according to other parameter choice in Processing script using QGIS 3?

I couldn't find anything about this problem. Suppose to have the first parameters in a Processing script defined as an Enum: self.addParameter( QgsProcessingParameterEnum( ...
1
vote
1answer
76 views

VectorWriter analog in QGIS 3 API

It seems that in API for QGIS 3 VectorWriter was replaced: from processing.tools.vector import VectorWriter returns ImportError: cannot import name 'VectorWriter'. How do I rewrite following things ...
0
votes
0answers
30 views

Linear Referencing of Street signs with the road segment

I have Street sign layer, which is a point data and a road segment layer, which is line data. These layers are no way connected by attributes but spatial fits perfectly together (But they don't ...
0
votes
0answers
27 views

Displaying rasters in a folder | QGIS 3.0.3

I have a satellite image. And in the folder where this picture is stored, it is well displayed. But when I divide it with the help of script into parts and save in a separate folder, then get such a ...
0
votes
0answers
25 views

QGIS python console: Overlapping letters

In QGIS Python console and Processing toolbox > Script editor, the code letters are overlapping. I have this behavior on two different computers, both with win10 and QGIS 3.0.3. There is something ...
2
votes
0answers
67 views

Alternatives to QGIS raster calculator?

I am using QGIS 3 on a Mac. I have a large raster (bfd.tif size is 26000, 31800) that I'm trying to apply a calculation to. When I use the default raster calculator in QGIS 3 I get a raster back with ...
1
vote
0answers
72 views

QGIS 3: saga algorithm in console

I'm trying to use the saga algorithm 'quadtree structure to polygon' (with points to get polygons), in the python console. But I think I'm not able to set the parameters correctly. When I call the ...
2
votes
0answers
29 views

Optimising script from QGIS modeler?

I am new to QGIS and got my hands dirty using the processing modeler. the task is to perform zonal statistics to get total area of classes in a raster layer against classes in a vector layer. the ...
3
votes
2answers
44 views

Rectangle Buffer (with dimensions given in metres) around Points on map (lat long). Using QGIS 3.0

I have points on a map of the globe given with lat|long coordinates. I want to create a rectangular buffer around each one, but I want to be able to set the dimension of this buffer in metres. The ...