GIS Dictionary

Definitions for GIS terms related to operations such as analysis, GIS modeling and web-based GIS, cartography, and Esri software.

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N-ary association

See Also: association

  1. [programming] A UML term that describes how two classes have a relationship with one or more other classes. In an N-ary association, instances of the classes in question usually exist together, but can exist on their own. For example, a three-way valve usually has one size of pipe coming in and two other sized pipes going out. Before the pipes and valve are connected into the water system they are separate parts; therefore, they have an N-ary association.