and the vertex A corner or a point where lines meet. Other types of point features include the node The intersection points where two or more arcs meet. Points have only the property of location. Points are typically used to model singular, discrete features such as buildings, wells, power poles, sample locations, and so forth. are zero-dimensional objects that contain only a single coordinate pair. In a GIS, points have only the property of location. Points A zero-dimensional object containing a single coordinate pair. Three fundamental vector types exist in geographic information systems (GISs): points, lines, and polygons ( Figure 4.8 "Points, Lines, and Polygons"). The spatial information and the attribute information for these models are linked via a simple identification number that is given to each feature in a map. The data attributes of these features are then stored in a separate database management system. Geographic Information Systems: A Management Perspective. Vector data models use points and their associated X, Y coordinate pairs to represent the vertices of spatial features, much as if they were being drawn on a map by hand (Aronoff 1989). In this model, space is not quantized into discrete grid cells like the raster model. In contrast to the raster data model is the vector data model.
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