Editing Data model (section)

=== Geographic data model ===
{{Main|Data model (GIS)}}
A data model in [[Geographic information system]]s is a mathematical construct for representing geographic objects or surfaces as data. For example, 
* the [[vector graphics|vector]] data model represents geography as points, lines, and polygons
* the raster data model represents geography as cell matrixes that store numeric values;
* and the [[Triangulated irregular network]] (TIN) data model represents geography as sets of contiguous, nonoverlapping triangles.<ref>Wade, T. and Sommer, S. eds. ''[http://store.esri.com/esri/showdetl.cfm?SID=2&Product_ID=868&Category_ID=49 A to Z GIS]''</ref>

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Image:Groups relate to the process of making a map.jpg|Groups relate to process of making a map<ref name= "DRS03">David R. Soller1 and Thomas M. Berg (2003). [http://pubs.usgs.gov/of/2003/of03-471/soller1/index.html The National Geologic Map Database Project: Overview and Progress] U.S. Geological Survey Open-File Report 03–471.</ref>
Image:NGMDB data model application.jpg|NGMDB data model applications<ref name= "DRS03"/> 
Image:NGMDB databases linked together.jpg|NGMDB databases linked together<ref name= "DRS03"/> 
Image:Representing three-dimensional map information.jpg|Representing 3D map information<ref name= "DRS03"/> 
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