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In geographic information systems, a feature is an object that can have a geographic location and other properties. [1] Common types of geometries include points, arcs, and polygons. Carriageways and cadastres are examples of feature data. Features can be labeled when displayed on a map.
The shapefile format is a digital vector storage format for storing geographic location and associated attribute information. This format lacks the capacity to store topological information. The shapefile format was introduced with ArcView GIS version 2 in the early 1990s. It is now possible to read and write geographical datasets using the ...
Because the world is much more complex than can be represented in a computer, all geospatial data are incomplete approximations of the world. [9] Thus, most geospatial data models encode some form of strategy for collecting a finite sample of an often infinite domain, and a structure to organize the sample in such a way as to enable interpolation of the nature of the unsampled portion.
For example, a Building feature in a particular GML application schema might have a position given by the primitive GML geometry object type Point. However, the Building is a separate entity from the Point that defines its position. In addition, a feature may have several geometry properties (or none at all), for example an extent and a position.
(Example: a new road is added). Vector data allows much more analysis capability, especially for "networks" such as roads, power, rail, telecommunications, etc. (Examples: Best route, largest port, airfields connected to two-lane highways). Raster data will not have all the characteristics of the features it displays.
The origin of the geodatabase was in the mid-1990s during the emergence of the first spatial databases.One early approach to integrating relational databases and GIS was the use of server middleware, a third-party program that stores the spatial data in database tables in a custom format, and translates it dynamically into a logical model that can be understood by the client software.
Shapefile (Esri 1992–present) As the GIS industry grew to incorporate more casual users, the inherent complexity of the coverage data structure became a concern. When Esri released ArcView GIS 2.0 in 1992, it introduced the new shapefile format for vector data. This was a much simpler data model, eliminating features such as topology, but was ...
SoilGrids1km is a collection of updatable soil property and class maps of the world at a resolution of 1 km produced using state-of-the-art model-based statistical methods. Presents estimates (means and 90% confidence intervals) for pH, texture (sa, si, cl), organic carbon and more for 6 depth layers up to 2 m depth.