I have two polygons layers, and I'm looking to find the % Area of layer A polygons that are placed inside layer B polygons. (some of them are totally inside ,so I expect to get the result "1", and some of them are half in and half in other polygon, so I expect to get "0.5" for both polygons of layer B)
When i'm using the Intersection tool (Vector->Geoprocessing tools), I get the following error: "Input layer A contains invalid geometries (Feature 1426). Unable to complete intersection algorithm."
When I try to use the "Join Attributes by Location" tool (Vector->Data Management Tool),using "Intersects" Geometric Predicate, I get a table with all layers A that intersect layer B, that's great but I can't calculate the % area of layer A polygons that are inside layer B polygons.
I'm using QGIS 2.18.4. Both layers are CRS EPSG:4326, WGS 84. Any advice?