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Explore the different spatial data models, including raster, vector, and hybrid systems, for organizing and analyzing spatial data. Learn about the advantages and disadvantages of each model and their applications in various fields.
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Spatial data models • Raster • exhaustive regular or irregular partitioning of space • associated with the field view • location-based • Vector • points, lines, areas • associated with the object view • object-based
Vector data models • An object (as opposed to field or location) viewpoint of space • represent geographic entities as discrete objects composed of points, lines, and polygons
Vector data models • Spaghetti vector data model • each point, line, or polygon that represents a geographic entity is stored as a record in a file that consists of that entity’s ID and a list of coordinates that define it’s location (or the coordinate space that it occupies)
Vector data models • Spaghetti vector data model • relationships among objects are implied
Vector data models • Spaghetti vector data model • advantages • simple • efficient for display and plotting • disadvantages • inefficient for most types of spatial analysis
Vector data models • Vector topologic data model • composed of points, lines, and polygons • node: a point at the intersection of two or more lines • in addition to coordinate locations, the topologic relationships between geometric features are explicitly recorded
Vector data models • Vector topologic data model
Vector data models • Vector topologic data model
Vector data models • Vector topologic data model: GBF/DIME
Vector data models • Vector topologic data model: POLYVRT (hierarchical data structure)
Vector data models • Freeman - Hoffman chain-code for compacting vector storage
Vector data model • TIN: Triangulated Irregular Network
Vector data model TIN: Triangulated Irregular Network
Vector data model • TIN: Triangulated Irregular Network
Vector data model • Hybrid vs. integrated systems for vector data models • A hybrid system stores spatial data in one type of data model and the attribute data in another data model that is often an existing commercial non-spatial database • An integrated system manages both spatial and attribute data using the same data model
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