Questions tagged [qgis-modeler]
An application of QGIS used to develop models utilizing a large variety of powerful Geoprocessing tools via a GUI.
335
questions
2
votes
1answer
73 views
QGIS Extract by Expression with multiple polylines in Processing Modeler
I'm trying to get the matching features from an intersecting vector layer. I can manually open Extract by expression tool and put the expression like intersects($geometry, geometry(get_feature('Liness'...
1
vote
0answers
15 views
Processing: Using attribute as input for algorithm
In Processing Modeller, is it possible to pass a field value (attribute of a feature) to a file name?
Example:
I have raster, MyRaster.tif, and I would like to clip it by different polygons inside ...
3
votes
0answers
31 views
Manually giving input and output for QGIS graphical modeler exported python script
I am using QGIS 3.
How could I manually give the input layer and the output path to the following script extracted from the graphical modeler?
It is a simple model, it takes a DEM as input and ...
2
votes
0answers
25 views
Using Python code from QGIS 3.x Graphical Modeler in console?
I want to use "Join Attribute by Location (summary)" processing algorithm in Python console of QGIS 3.10. After design my algorithm process (join sum of field name "abc" form layer 2 (point layer) to ...
6
votes
1answer
222 views
Extracting features with equal field value using graphical modeler of QGIS
Is it possible to automate the following procedure with graphical modeler in qgis 3.4 or is it easier to perform such action with a python script using PyQGIS?
Identify a feature (a line) in a vector ...
2
votes
1answer
30 views
Sort or add Rank within QGIS 3 model
I have the following function in order to add a sorting value to a layer:
array_find( array_sort( array_agg("field")), "field")
This works fine if I use it through the calculator within the ...
3
votes
0answers
47 views
Error while running batch processing in QGIS 3
I have built a straightforward model in the Graphical Modeller in QGIS 3.4 to select features by expression and then save the selected features to a new shapefile.
It works when running singly but ...
10
votes
2answers
135 views
Using Viewshed Graphical Modeler
I am trying to create a viewshed using the graphical modeler, the first part involves creating the viewpoints which works fine, however when I create the viewshed I get the following error. Also, when ...
0
votes
0answers
17 views
Join fields QGIS processing framework [duplicate]
Using QGIS 3.4.12-Madeira
I'm building a model using the algorithm 'Join attributes by location'.
In my operation i want to join several fields from a layer, but not all.
I tried to set one field ...
3
votes
2answers
60 views
Iterate over all attributes in QGIS Graphical Modeler
I would like to iterate over N unknown attributes in the QGIS Graphical Modeler.
For example dividing all attributes in an input layer by its area to create an area weighting.
I realise it could be ...
2
votes
1answer
33 views
How to call for Matrix Parameter / Enum Parameter using Field Calculator in the graphical modeler of QGis?
I am using QGis Graphical Modeler v.3
It is possible to define, as an Input, a Matrix, defined as follows:
"A table (matrix) parameter for processing algorithms".
I want to use values stored within a ...
1
vote
0answers
70 views
Converting Model in Plug-in in QGIS [closed]
Recently, I started making a model on QGIS and now I want to transform it into a plug-in, but it seems that I have to change the code to do it, otherwise it won't work.
What changes are required to ...
5
votes
1answer
253 views
Exporting result of QGIS model to CSV
I am trying to output the result of a QGIS 3 model as a CSV file. At first I came across How to export csv/excel in QGIS3.0 model processor? but the accepted answer is not satisfying to me. Further ...
2
votes
1answer
33 views
Collapse rows with different attributes in QGIS modeler
I am trying to build a QGIS modeler tool to do the following;
I have a parcel table with fields "OWNER" and "OWNERNO" where each owner has their own row in the table and the "OWNERNO" numbers them. (...
1
vote
0answers
32 views
Using project layers as input to the graphical modeler exported script in the Python console (QGIS)
I have created an workflow wothin graphical modeler in QGIS.
Now I want to use the code exported from the graphical modeler in the python console.
How could I use the layers from my project as ...
1
vote
1answer
39 views
QGIS 3.4.4 edit rendering styles for outputs - styles not loading
I have created a processing model in version 3.4.4 and I want the shapefile outputs from the model to load in a chosen style. I have saved the style files and used the 'edit rendering styles for ...
3
votes
1answer
62 views
Standalone Python application from QGIS graphical modeler
I am trying to run the script generated by my graphical modeller through QGIS script. But I get the following error.
# Prepare the environment
import sys
from qgis.core import QgsApplication
#from ...
2
votes
1answer
88 views
Change Output name in Script - QGIS 3
I exported a model as script using the properly option in QGIS 3.8.
The Script works perfectly, but the output name is changed.
Heres a print of the model:
I want that the script´s output name, from ...
1
vote
0answers
39 views
Problems with Zonal Statistic in graphical modeler QGIS 3
I want to make an average of two rasters previously generated in a model but it always gives error. I have used both SAGA and GDAL to calculate the raster out of graphical modeler without problems, ...
1
vote
1answer
72 views
QGIS 3 Graphical Modeler field calculator with attribute's parameters
I want to make a model with a vector layer to calculate the sum of two parameters contained in the attribute table of the layer.
I want to create two variables in the model, the name of the two ...
3
votes
1answer
49 views
Rotation goes Wrong
I have a model that I built using model builder that creates a rectangle grid and then rotates it. For some reason, when I use rotate, it creates something wrong-
and it creates''holes'' between the ...
1
vote
2answers
49 views
Realising vector file mapping using QGIS Modeler?
I pretty often get lots of vector files with different column namings. I need to produce a defined vector data file with certain columns. Is it possible to build a model that allows to make a mapping? ...
0
votes
0answers
17 views
Using Model Builder for QGIS? [duplicate]
I'm looking for a "model builder" for QGIS 3.2.1.
If that kind of tool exists, could someone share some related topic showing how to use it?
1
vote
0answers
20 views
Raster Calculator in the Graphical Modeler of QGIS 2.18
How to convert this expression from raster calculator
("noise_heatmap_clip@1" <= 50) * 5 +
("noise_heatmap_clip@1" > 50 AND "noise_heatmap_clip@1" <= 100) * 4 +
("noise_heatmap_clip@1" > ...
1
vote
1answer
40 views
Using Multiple Raster Intermediate Inputs in Raster Calculator within QGIS Process Modeler
I am stringing together a series of raster calculations in the QGIS process modeler in order to calculate a surface temperature dataset from Landsat and weather data.
When I use the output from ...
1
vote
0answers
44 views
Raster statistic
i'm try to use QGIS processing modeler but I've a problem.
I need to use the Mean value and the standard deviation in raster calculator algorithm. I've calculated it in raster statistics, how can I do ...
0
votes
1answer
29 views
QGIS Modeler - drag and drop data from ToC
Is it possible to drag and drop data from the ToC to a graphical modeler and then draw connections between data and algorithms?
Also can we do the same with items in the history panel?
This would ...
3
votes
1answer
54 views
Adding a Geopackage layer as a hardwired input to an algorithm in the QGIS graphical modeler
I have a geopackage layer that I want to always be used in an algorithm in the QGIS 3.6 graphical modeler. When I use the triple dots to navigate to the geopackage it doesn't give me the option to ...
0
votes
2answers
52 views
Downloading files with file paths informed by attribute information
I am looking to download files that are saved in a server location with a file path that is informed by attribute information created in the graphical modeler.
The information that I would like to ...
2
votes
0answers
105 views
QGIS3 run model with python script
I want to run a model with a python script, including the parameters, because I can't "translate" the model easily into a script.
I have tried to run a copy of the processing log after running the ...
1
vote
0answers
18 views
Loading rasters from a GeoPackage into QGIS modeler based on attribute information?
I am looking to load raster layers from a GeoPackage based on strings of attribute information that is stored in a field. The process I am looking for is as follows:
Site Boundary created before the ...
4
votes
1answer
132 views
Using variable in graphical modeler for raster calculation? (QGIS 3.8)
I am trying to create a flow in the graphical modeler using a variable in a raster calculation. Is there a way to use a variable directly in the raster calculator (SAGA or GDAL)? I know there was a ...
2
votes
0answers
43 views
Save Selected Features in QGIS 3.4 Model
I'm trying to build some models I have in QGIS 2.18. Each model uses the "Save Selected Features" geoalgorithm so that the model only runs on selected features in the source vector layer.
In 3.4 ...
2
votes
1answer
50 views
Python error when batching a Graphical Modeler script [QGIS 3.4.9]
I have a very simple Model to convert a table in points and to extract some features by their attributes. I can run it without any problem, except if I do it as a batching process.
I received this ...
1
vote
1answer
40 views
Writing comments in QGIS Graphical Modeler?
Is it possible to write comments in the Graphical Modeler (QGis) ?
I want to explain my model step by step so anyone can easely understand what's going on.
3
votes
1answer
312 views
QGIS 3.8 model to Python script, not working in 3.4
I am using QGIS 3.4 but it does not have the option of saving a model to a Python script. So I installed QGIS 3.8, which has that option, loaded my model and saved it as a Python script.
I loaded the ...
2
votes
0answers
24 views
QGIS 3.4 Modeler gives error on non-required parameter?
I created a model which is asking to input 20 OPTIONAL parameters for vector layers.
But when the user does not enter a value for any of the 20 parameters, QGIS returns an error.
Traceback (most ...
1
vote
0answers
21 views
Ability in QGIS modeler to just run a step or subsequent steps in a model
In the current QGIS LTR is it possible to just run one step or all subsequent steps in a model if the previous steps have all been run and are not changed?
Sometimes steps take hours to run so if ...
1
vote
0answers
44 views
When using QGIS Modeler with geopackages is there any way to Extract one Specific layer when using clip function?
I would like to use QGIS modeler to allow extraction of certain layers of a geopackage.
I am trying to clip a geopackage containing multiple layers using modeler and when run it the output gives only ...
5
votes
1answer
108 views
Order of parameters in QGIS 3.6 graphical modeller
When using graphical modeler in QGIS 3.6 I have added additional parameters to the model inputs for the buffer tool.
The model looks like this:
When running the tool the order of the parameters in ...
0
votes
1answer
24 views
qgis:deletecolumn in QGIS 3 graphical modeler
I want to use the algorithm qgis:deletecolumn in a graphical modeler.
How do I have to fill the case Fields to delete :
["field1","field2"]
"field1","field2"
field1,field2
[field1,field2]
And is ...
1
vote
0answers
22 views
Copy all features and attributes to a new dataset based on a template in QGIS Modeler
In QGIS desktop I can merge a template spatial file that has no data but all the attributes I need with another spatial file that has the spatial data where some of the attributes aren't in the ...
2
votes
1answer
49 views
Compare two columns using Graphical Modeler in QGIS
I have a layer with several columns. One of them is called 'cod' and the other is called 'cod_2'. 'cod_2' is null, except for one row. I want to know if the numerical value of 'cod_2' is present in ...
2
votes
0answers
17 views
Including metadata on QGIS 3 models?
Models on QGIS 3 are stored following a XML schema. Do you know if it is possible to embed metadata, may be using Dulin Core or ISO? I have noted that the modeler's help take in account subjects like: ...
2
votes
1answer
42 views
QGIS 3.4 Modeler: Select a band of a raster layer for processing
As model input data I select a raster stack with three bands. The first processing tool just needs specific bands of this stack which I like to select in the input dialog.
I create a 'Raster Layer' ...
2
votes
1answer
70 views
Why QGIS3 is not running processing models and scripts in background?
I have a problem with QGIS 3.6.0 on macos and QGIS3.2.3 on Windows7 with running processing scripts and models in background. According to QGIS3 docs they are run in background thread by default (if ...
3
votes
1answer
175 views
Incorrect result while adding points along geometry in QGIS
I'm trying to add points along lines every 3 metres but I'd like the starting/ending point at certain non fixed distance. When I use the tool 'Points along geometry' inside Graphical Modeler. I don't ...
5
votes
1answer
203 views
Model works for single layer but errors for batch process
I have a pretty simple model in QGIS that I am trying to use as a batch process.
The model takes a line shapefile input, creates a temporary buffer, extracts by location using that created buffer, ...
1
vote
1answer
28 views
How to enter text into attribute tables with QGIS graphical model?
I am using QGIS 2.14 to open NC files for chlorophyll satellite data with the end goal of compiling chlorophyll values for many dates (each its own initial file) in a spreadsheet. I know how to do the ...
3
votes
0answers
57 views
How to chain multiple field calculators in QGIS Modeler with pointers on next or previous feature?
I have a Model that I use to filter a chain of points that have extracted values form a DEM (digital elevation model). I want to smoothen the hights with a filter that takes the average of the ...
