Automating Complex Workflows using Processing Modeler (QGIS3) — QGIS Tutorials and Tips

[utterances-bot]

Automating Complex Workflows using Processing Modeler (QGIS3) — QGIS Tutorials and Tips

https://www.qgistutorials.com/en/docs/3/processing_graphical_modeler.html

[Faodero]

Hi Ujaval. Thanks for putting together these tutorial. When I get to step 23 and run the model, I do not get the aggragate layer. There is a part of the model that says "No spatial index exists for input layer, performance will be serverly delayed". Might you know what the problem could be? The layer is not added to my laptop as well.

[spatialthoughts]

The problem with not having the output layer could be due to many reasons. The main issue many users face is that they have not set the CRS correctly as specified in step 20. Check your project again and make sure you have done each step correctly. A useful debugging technique is to add 1 step to the model, enter a name in the model algorithm and run the model. If the output gets generated without errors, you did that step correctly. Remove the layer name and add the next step. Repeat.

The spatial index warning is because of missing spatial index. It can be added as a step in the model. See step-by-step at https://courses.spatialthoughts.com/advanced-qgis.html#concept-spatial-indexing

[narges-mohammadi]

Step 6: On he left-hand --> On the left-hand Step 16: By compating --> By comparing

[spatialthoughts]

Thanks. Fixed in da626bf5ae50f1d8b065b7c9f62d54e0000663c6

[SHsabbir25]

@spatialthoughts why it occurs- Error encountered while running Create grid: To preserve symmetry, hspacing is fixed relative to vspacing hspacing is fixed at: 0.866025 and hoverlay is fixed at: -99999.1 hoverlay cannot be negative. Increase hoverlay.

[spatialthoughts]

@SHsabbir25 Check your CRS. It should be set to Mollweide before running the model.