A GIS tool for vector datasets that retains the areas on two layers where features do not intersect with each other.

A GIS tool for vector datasets that retains the areas on two layers where features do not intersect with each other.

• A. Union
• B. Intersection
• C. Difference
• D. Symmetrical Difference

Answer: (D)

Non-overlapping areas between two vector layers are what this operation captures. Symmetrical difference returns the parts that belong to either layer but not to both, effectively keeping the non-overlapping portions from each dataset. In other words, it computes (A union B) minus (A intersect B), so you get the areas of A outside the overlap with B and the areas of B outside the overlap with A. This makes it ideal when you want to see everything that is unique to each layer rather than the shared region. By contrast, union would include the overlapping area as well, intersection would keep only the overlap, and difference would yield only the parts of one layer minus the overlapping portion with the other (and would depend on which layer you subtract from).

Non-overlapping areas between two vector layers are what this operation captures. Symmetrical difference returns the parts that belong to either layer but not to both, effectively keeping the non-overlapping portions from each dataset. In other words, it computes (A union B) minus (A intersect B), so you get the areas of A outside the overlap with B and the areas of B outside the overlap with A. This makes it ideal when you want to see everything that is unique to each layer rather than the shared region. By contrast, union would include the overlapping area as well, intersection would keep only the overlap, and difference would yield only the parts of one layer minus the overlapping portion with the other (and would depend on which layer you subtract from).