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Showing posts with the label GIS Data

Vector Data Model of GIS

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Vector Data ModelVector Data Model is an object based approach to the representation of real world features. This data model is best suited to represent discreet objects. In this method the entire earth surface feature including man-made and natural can be represented by only three entities in GIS. These entities name- PointLine Polygon In this all the features in which only locations is presented than Point entity used for representation in GIS, However for representation of all linear features, line entity used in GIS. To represent any enclosed feature of earth and representation of any feature which has area entity, in that case, polygon entity is used in vector data. This representation also called spatial data in GIS.

Example: Vector GIS Data Point- Hospitals, Wells etc.Line- Highway, River, Canal etc.Polygon- Forest, Agri Land, Urban Area etc.This spatial data also have information, which need to represent in GIS vector data. Such as in case of point feature Hospital, information s…

Raster Data Formats in GIS

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Raster Data FormatsSpatial Data in GIS has two primary data formats Raster Vector Earliest GIS software was either Raster based or Vector based, but now most of the GIS software has data processing capabilities in both formats. Advances in computer technology have largely eliminated the boundaries between Raster and Vector data for GISapplications. An integrated raster and vector data working environment provides many more opportunities as you can combine the methods suitable for both the formats in your analysis. Both formats have their advantages and disadvantages. RASTER DATA Raster data have become the primary source of spatial data in geographic databases and are used increasingly in a wide variety of GIS applications.Raster data defined as representing earth surface feature including manmade and natural in grid/cell forms. Its mean all the raster data represented by image, cell and grid formats. The satellite images are recorded in raster format. Representationof Raster DataRaster d…

GIS Data-Spatial and Non-Spatial Data

Data is raw form of information, which is given to the computer for processing. However, database is an organized collection of related data. Database should be integrated, structured and shared. So here we can say that GIS is both a database system with specific capabilities for spatially referenced data as well as a set of operations for working with the data. 
GIS database consist of sets of information called Layers. Each layer represents a particular type/class of geographic data. For example, one layer may include information on the road network in an area. Another layer may contain information on the land use in that area, while another records soil, elevation etc.
The GIS can combine these layers into one image, showing how the road network, land use, soil, and elevation relate to one another. Engineers/ Scientists might use this image to determine areas with more urban growth/ urban sprawl, loss of agriculture land etc. GIS can help to answer several questions for any applica…