Questions tagged [qgis-modeler]

An application of QGIS used to develop models utilizing a large variety of powerful Geoprocessing tools via a GUI.

113 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
6
votes
0answers
140 views

Using Layer Parameter variables in Field Calculator within QGIS Model?

If I define a Vector Layer as an input parameter to a QGIS model, then the parameter name is exposed as a variable in a Field Calculator within the model, however I am unable to use this variable as I ...
5
votes
0answers
56 views

Referencing an output in an expression in process modeler

In the process modeler, I'd like to reference an output of a previous step as one of the parameters of an algorithm. In this case, the previous step was clipping a large raster and I want to use the ...
5
votes
0answers
133 views

Creating Viewsheds in Graphic Modeler

I am trying to use Graphic Modeler to run viewsheds. As I can’t appear to use the Viewshed Analysis plugin tool in Graphic Modeler and I instead need to use the GRASS command r.viewshed. I am ...
5
votes
0answers
99 views

Selecting minimum number of neighbouring polygons required to give a fixed total area

I have a polygon layer. I would like to select the minimum number of neighbouring polygons to give a total area greater than a fixed value. In reality the polygons are land parcels and I would like to ...
5
votes
0answers
321 views

QGIS modeler - use input filename in output filename

I need to use the input filename in the output filename in a QGIS model. I have spent a couple of hours trying to find a solution but can't. If the input is contourXY.tab and I want output to be \...
4
votes
0answers
761 views

Problem loading output layer QGIS

Every time I run operations with temporary file output from the graphical modeler, I get the following error message: Oooops! The following output layers could not be open CLIP: C:\Users\Amine\...
3
votes
0answers
26 views

Exporting rendered raster image from graphical modeler

I am new to using the graphical modeler and am trying to export the result raster from my model as a rendered image. Basically trying to replicate what happens by doing the following to the result ...
3
votes
0answers
34 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 ...
3
votes
0answers
52 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 ...
3
votes
0answers
61 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 ...
3
votes
1answer
211 views

File naming iteration QGIS modeler

I am attempting my first use of the modeler from the Graphical Modeler from the Processing menu in QGIS. I made a simple model for cliping species data by sanctuary.It has two Vector Inputs, uses some ...
3
votes
0answers
75 views

Setting output filenames from QGIS modeler?

I have built model which iterate through features in input layer. How I can set output filenames in the modeler using input rows? Something like current_field_value.shp
3
votes
0answers
228 views

QGIS spatial sort - coalesce?

In QGIS (v3.2) is there a spatial sort similar to ArcGIS (http://desktop.arcgis.com/en/arcmap/latest/tools/data-management-toolbox/how-sort-works.htm#ESRI_SECTION1_9C199CD3D68A41029943D4FF79500A73) ...
3
votes
0answers
133 views

Using raster calculator inside graphical modeler

I have an issue, which I am struggling with since few hours - I've built a model which aims to make multicriterial analysis based on few vector layers and DEM. At the step which is problematic for ...
3
votes
0answers
72 views

Python stops during band algebra in GDAL calculator within modeler in QGIS

I'm trying to calculate four greenness indices using the GDAL calculator within the graphic modeler in QGIS 2.14.7 Essen. The tool systematically crashes with a Windows message stating that Python ...
3
votes
0answers
279 views

Multilevel b-spline crs issue in modeler

I'm struggling with a processing modeler tool. I have a point shapefile (WGS84) which I want to interpolate with the SAGA spline tool. The model is reprojecting the wgs84-points to UTM32N (EPSG:25832)....
3
votes
0answers
171 views

How to use Hub distance in a processing model?

I am trying to make line layer (hub distance layer ) between two point layer in QGIS 2.16. It works fine when I make layers step by step but, I want to make MODEL in processing modeler and ...
3
votes
0answers
824 views

Download OSM data with QuickOSM and QGIS Modeler

I've been using QuickOSM plugin for some time and I would like to create some model that allows me to automate OSM data dowload in order to make sure that I am always working with the most updated ...
3
votes
0answers
255 views

Splitting OSM data into layers by tags (QGIS modeler)

I have a problem with using the QGIS modeler to split a downloaded .osm file into layers. What I am trying to achieve is a structure like this: Traffic (lines) Main Roads Roads Small Roads Natural (...
3
votes
0answers
106 views

Missing list of algs in QGIS 2.14 Processing modeler?

I changed my QGIS-version from 2.8 to 2.14. I am very happy that v.net algs (grass7) are available now as part of the processing plugin. But now there is no list of algs inside the modeler - so no ...
3
votes
0answers
192 views

Clipping and reprojecting in one process for modelbuilder // “Save raster layer as” … in modelbuilder

I want to build a model in the QGIS Modelbuilder. First it should do a clip. Afterwards it should be reprojected (from Geographic WGS84 Coordinates to Gauss-Krüger). I only see one way to do this: ...
3
votes
0answers
183 views

IS it possible to run GRASS commands in the QGIS graphical modeler?

I have a geoalgorithm set up in the graphical modeler and everything runs except for the GRASS commands. It is really frustrating because when I execute these commands on their own they work just fine ...
3
votes
1answer
419 views

What's the correct syntax for Execute SQL in Processing QGIS 2.6?

I made a small model with Processing in QGIS 2.6. The final layer should be the result of a SQL query. Now, in the Execute SQL dialog window I can add the query: select name, max(ele) as ele, geom ...
2
votes
0answers
18 views

Qgis SAGA Upslope Area for several points automation

In the Upslope Area tool from SAGA it used to be possible to import the point file with multiple points and it would create several catchment/basins areas for those points. Now, it is only possible to ...
2
votes
0answers
31 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 ...
2
votes
1answer
39 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 ...
2
votes
0answers
118 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 ...
2
votes
0answers
45 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
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 ...
2
votes
0answers
18 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
102 views

Python script from graphical modeller of QGIS 3.4 gives KeyError?

For several tasks in QGIS 3.4 I need a python script. As I am not used to use python I created the script with the graphical modeler (I modeled the tasks in the graphical modeler and exported the ...
2
votes
0answers
26 views

Merge Vectorfile Outputs from Model Batchprocess in QGIS

I have written a model in QGIS 3.6 that allows to vectorize the outlines of raster layers containing measurement data. I run this model as a batch process to vectorize several field outlines in one go....
2
votes
0answers
71 views

Method in QGIS to do a select by radius but ignore “islands”

I am looking for a process in QGIS to run a selection from a given point based of a radius that ignores "islands". For example you may have a body of water which acts as a natural barrier past which I ...
2
votes
0answers
22 views

Error in Graphical Modeler when converting raster to vector

I'm building a model where, among other things, I use r.watershed, from which I only keep the "stream segments" output. In addition I would like to convert that raster to vector lines. When I do that ...
2
votes
0answers
54 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 ...
2
votes
0answers
111 views

QGIS: processing-modeler to add multiple layer name to attribute field

I'm trying to add layer name using the field-calculator in QGIS (3.4.1). If I do this manualy it works fine, but if I do this using the processing-modeler I get NULL for every field. I just type @...
2
votes
0answers
28 views

Pass additional options to GDAL in QGIS v3

I'm using gdalwarp inside a QGis v3 model (using qgismodeler) and I'd like to pass the -tap option to the command. I can't find where to place this. Is it possible to add additional options to gdal ...
2
votes
0answers
158 views

What to use instead of 'Table' input in QGIS 3 modeller

In QGIS 2 graphical modeler I had an input parameter 'Table' for spreadsheets, csv etc. with no geometry. By now, I'm re-creating all my existing QGIS 2 models from scratch (cp. Using QGIS 2.x ...
2
votes
0answers
33 views

How to make QGIS model result to be a variable?

My model's temporary result is a point layer (one feature) and I need a value from one of its fields because I want to use it in the same model to select a feature on another layer. So for example, ...
2
votes
1answer
372 views

Vector Fields as Input Variable in Field Calculator

I’m working with QGIS 3.2 Bonn and I try to build a workflow in the graphic modeler. The model aims to build variable buffers depending on values from two attribute fields of an input vector layer. ...
2
votes
0answers
106 views

Convert polygons to lines ignoring redundant vertices in QGIS

Provided the following Polygons layer with 6 polygons (see image below), I would like to calculate each line's segment's angle (amongst other things), so I should convert those six polygons into lines,...
2
votes
0answers
69 views

QGIS Modeler Layer order

Is there a way to Order the way Layers are displayed when adding them to a process in the modeler? I am trying to add 4 layers to a VRT process before using a Clip by polygon function and the problem ...
2
votes
0answers
146 views

Processing modeler to update table

Not sure if I'm missing something very basic or not, but I have 6 or 7 shapefile vector layers in a dozen or so models that I need to update a single field with a rather simple formula. I could spend ...
2
votes
0answers
56 views

Is there a way to view Qgis models from version 2.14 so they can be recreated in 3.0

I upgraded my qgis version from 2.14 to 3.0 and didn't realize that the models from the graphic modeler are not compatible. Is there a way to view or read the models so I can recreate them in 3.0? I ...
2
votes
0answers
106 views

Run graphical modeler on multiple pairs of selected features

I have a shapefile of 10,000+ county polygons. Of these, I've identified ~5,000 that are geographically too small, and I want to combine with their immediate nearest neighbor, naming the combined ...
2
votes
0answers
229 views

Handing a Bounding Box (bbox) to an overpass query

I would like to incorporate the results of overpass-queries into a model, which in the end gives me a clipped union of these results (all roads within a specific area). The challenge is to automate ...
2
votes
0answers
140 views

How to make a database to be a model parameter in QGIS?

I built a model in QGIS that imports vector into PostGIS database. My only problem is that I can choose which database I would like to import my data into but only if I rightclick on the model and ...
2
votes
0answers
71 views

QGIS Modeler Input WMTS

Maybe I'm just missing something here, but i can't figure out how to set a WMTS Layer as an Input Parameter in QGIS Modeler. I just wanted batch the process of exporting a GeoTiff from a WMTS Layer. ...
2
votes
0answers
104 views

Choose which MULTIPLE attributes should be joined -QGIS Graphical Modeler

I need to select which MULTIPLE attributes to join in a QGIS model. It allows me to do this in the interface (Properties-->Join) but not in the QGIS Model version of Join by Attribute. So I want the ...
2
votes
0answers
160 views

Median and Mode estimations in the QGIS Modeler?

I would like to know if there is anyway in which I can combine the available tools in QGIS in the Modeler to estimate median and mode values from a raster (DEM) using polygons. I know the zonal ...