Hi Roland,
I am assuming measure is a field name so what happens if you try measure=’1’? Cheers - Phil From: Qgis-user <[email protected]> On Behalf Of Roland Spielhofer Sent: Friday, 20 August 2021 7:20 PM To: qgis-user <[email protected]> Subject: [Qgis-user] Length of lines in polygon depending on attribute Hi, I have a polygon layer and a line layer. I would like to update a field in the polygon layer with the length of the lines in each polygon that have a certain value in an attribute. I thought I use the field calculator and the aggregate function but I did not succeed. What I have now is: aggregate( layer:='line_layer', aggregate:= 'sum', expression:='length', filter:='measure=1') which returns NULL In the line layer there is an attribute 'length' that already holds the length of the element. I only want the lines that have the attribute "measure=1". Any help appreciated! Regards, Roland
_______________________________________________ Qgis-user mailing list [email protected] List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
