Python script to set another layer inactive & select point by outside of boundary line?

Question

I have two layers, "IDN_ALL" as Polygon and "Point_Link" as point. "Point_Link" is the active layer. I want to select point data outside polygon data.

Code:

Layer1 = iface.activeLayer()
Layer2 = ??
layer1.selectByexpression("\"?..")

How can I select points outside polygons?

Answer 1

Try the options below. This will select all features in your point layer which lie outside of your polygon layer.

Note: Both layers should be in the same Coordinate Reference System, and in both cases make absolutely sure that the layer names match yours and are spelt correctly e.g. 'Point_Link' for the point layer and 'IDN_ALL' for the polygon layer.

Option 1- use processing algorithm 'Select By Location'

project = QgsProject().instance()
Layer1 = project.mapLayersByName('Point_Link')[0]
Layer2 = project.mapLayersByName('IDN_ALL')[0]
processing.run("qgis:selectbylocation", {'INPUT':Layer1,'PREDICATE':[6],'INTERSECT':Layer2,'METHOD':0})
Layer1.invertSelection()

Option 2- This approach avoids the use of processing, but will produce the same result.

project = QgsProject().instance()
Layer1 = project.mapLayersByName('Point_Link')[0]
Layer2 = project.mapLayersByName('IDN_ALL')[0]
index = QgsSpatialIndex(Layer1.getFeatures())
pntFts = [f for f in Layer1.getFeatures()]

pts2select = []
for f in Layer2.getFeatures():
    candidateIds = index.intersects(f.geometry().boundingBox())
    candidateFts = [f for f in pntFts if f.id() in candidateIds]
    for p in candidateFts:
        if p.geometry().within(f.geometry()):
            pts2select.append(p.id())
    
Layer1.selectByIds(pts2select)
Layer1.invertSelection()