I illustrate my problem: in practice I have a land use in vector format that is also made up of polygons irrelevant from a dimensional point of view but that I would like to delete for a question of structure of the file. These polygons have dimensions that are not very relevant for the scale that I have to produce (we are also talking about values around the square meter). Now, to avoid correcting them one by one, what semiautomatic methodology could I apply to ensure that these polygons are merged (using merge) to adjacent ones, both spatially and as an attribute? It 'clear that each minipolygon borders with different, however, given the scale I work at, it is indifferent whether these are merged with one or the other. I hope my question is clear!
-
Could you post a screenshot?– StefanBrand_EOXCommented Jul 7, 2018 at 14:02
-
How do you want to choose which landuse type is given to the merged feature? Would rasterizing be an option? Then you could just choose the spatial extent you think/know is right for you.– blabbathCommented Jul 7, 2018 at 14:06
-
Hi, thanks for the answers. No, I would just work with the shapefile– Giuseppe CillisCommented Jul 7, 2018 at 14:19
-
Not sure if I fully understand your question, but would simply deleting every polygon smaller than one squaremeter (or whatever threshold you want to use) be an valid option in your case?– tallistroanCommented Jul 7, 2018 at 15:55
-
I don't want to delete every polygon smaller than one squaremeter, but to merge every polygon smaller than one squaremeter to an adjacent polygon– Giuseppe CillisCommented Jul 7, 2018 at 16:05
1 Answer
Assuming you already have an attribute field containing the area of your polygons in your data, this could be the workflow:
Choose the "Select features by value" function in the toolbar
, in the popup specify your threshold, e.g. less than one sqm and click Select Features:
You get a notification that a number of matching features were selected.
Now choose Vector > Geoprocessing Tools > Eliminate Selected Polygons and in the new window choose the appropriate options and click Run. In the new layer the small polygons are merged to the nearest polygons in the way it was specified in the tool. Since the small polygons were deleted, also the attributes from these are not somehow merged into the bigger polygons.
In case you don't have an attribute field with the area of the polygons you can add it to your file using Vector > Geometry Tools > Add Geometry Attributes or by using the field calculator.
