40 UnionUse Union when you want to overlay two polygon layers so that the resulting output layera) has the combined attribute data of the polygons in the two inputs, andb) contains all the polygons from the inputs, whether or not they overlap.
41 UnionStart with Pittsburgh ZIP codes and Neighborhoods
46 IntersectUse Intersect when you want to overlay a layer with the polygons in another layer so that the resulting output layer- has the combined attribute data of the features in the two inputs, and- only contains features that fall within the spatial extent of the overlay polygons
50 Model Builder Workflow processes can be complicated Automates and strings functions together
51 Model Builder Problem: You have census tracts from a state with population data but only want population for neighborhoods in a small regionSolution:Use Model Builder functions to clip census tracts and union to aggregate data to neighborhoods
52 Model Builder ExampleBegin with census tracts for the state of Pennsylvania
53 Model Builder ExampleClip only tracts whose centers are located within Pittsburgh neighborhoodsUnion the census tracts and neighborhoods