Spatial and attribute data in GIS and their processing

摘要

A map represents geographic features and related spatial phenomena conveying information about locations with their attributes graphically. Spatial information describes the position of a geographic feature on the earth's surface as well as the spatial relationships between features. Attribute (nonspatial) data describe characteristics of the geographic features represented such as the feature type, its name, abundance, and quantitative information [e.g., area (of a soil unit) and length (of a river)].