I have two layers:

  1. point layer representing some house addresses.
  2. polygon layer representing some kind of territory.

What I'm trying to do is, create a model where I select the points inside the polygon using:

  1. "select by location"
  2. "extract selected feature" (+dependency),

Since the "select by location" can not be used in the modeler as an output. Then I am willing to change only the selected points field "Satellite" that intersects with the polygon, by changing it's value for example with a string 'test'.

CASE 1: I only managed to change this field in the New Layer: "TEST_LAYER" added in the field calculator. However this is not my intention , I want to update the field "Satellite" in "Points in the Polygon"-Layer.

Extract by location example:
enter image description here
----->Resulting in: enter image description here

Select by location + extract selected features example

Just trying the green colored function in the field calculator in the attribute table is working but not working in the modeler. Execute a field calculation on just selected records from Processing Toolbox in QGIS 3?

CASE 2: I managed to change the field "Satellite" to 'test' in the desired "Points in Polygon"-Layer but without making use of the previous selection. The whole column will update wheter or not is selected. In this case I made use of "Update Field" which is being provided by the Networks PlugIn. https://i.stack.imgur.com/5BPtM.jpg

The first example 1) can not update the field because the input from the extract by location is not valid The second example 2) is working changing the field in the "Points in the Polygon"-Layer but is not knowing anything about the selection. Dependency between the "Extract by location" and "Update field" is not helping.

Any ideas on how I can resolve this problem?

  • i listed all the cases that i could think about. none of them worked. I just want my modeler to write just for the selected points (that are within the polygon) in the satellite field a given string (without creating any new layer, just update). I don't have no preference which way it is done as long as the job is done. – Denis Crîlov Sep 10 '20 at 7:22

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