1 Answers
Anonymous answered 3 years ago
- There are three common spatial data models being used in GIS today: vector, raster, and triangulated irregular network(TIN).
- A vector data model defines discrete objects. Examples of discrete objects are fire hydrants, roads, ponds, or a cadastral.
- A vector data model is broken down into three basic types: points, lines, and polygons.
- All three of these types of vector data are composed of coordinates and attributes.
- The last vector data type is the polygon.
- A polygon is formed by a set of connected lines where the start and end of a point have the same coordinate.
- As the start and point have the same coordinate, the polygon will close and will have an interior region.
- Attribute information is attached to the center of the polygon no matter how complex the polygon. Examples of spatial phenomenon modeled well by polygons are lakes, cities, tree stands, and political boundaries.