File Name: raster and vector data structure in .zip
Vector graphics are computer graphics images that are defined in terms of points on a Cartesian plane , which are connected by lines and curves to form polygons and other shapes. Vector graphics have the unique advantage over raster graphics in that the points, lines, and curves may be scaled up or down to any resolution with no aliasing. The points determine the direction of the vector path ; each path may have various properties including values for stroke color, shape, curve, thickness, and fill. Instead of sectioning off a large region of computer memory and mapping that to the display device, vector display devices use a variable number of lines to create images—hence the term "vector graphics. There was a video game console that used vector graphics called Vectrex as well as various arcade games like Asteroids , Space Wars and many cinematronics titles such as Rip-Off , and Tail Gunner using vector monitors.
Raster and vector are two very different but common data formats used to store geospatial data. Vector data use X and Y coordinates to define the locations of points, lines, and areas polygons that correspond to map features such as fire hydrants, trails, and parcels. As such, vector data tend to define centers and edges of features. Raster data, on the other hand, use a matrix of square areas to define where features are located. These squares, also called pixels, cells, and grids, typically are of uniform size, and their size determines the detail that can be maintained in the dataset. Because raster data represent square areas, they describe interiors rather than boundaries as is the case with vector data. Vector data are excellent for capturing and storing spatial details, while raster data are well suited for capturing, storing, and analyzing data such as elevation, temperature, soil pH, etc.
In its simplest form, a raster consists of a matrix of cells or pixels organized into rows and columns or a grid where each cell contains a value representing information, such as temperature. Rasters are digital aerial photographs, imagery from satellites, digital pictures, or even scanned maps. Data stored in a raster format represents real-world phenomena:. Thematic and continuous rasters may be displayed as data layers along with other geographic data on your map but are often used as the source data for spatial analysis with the ArcGIS Spatial Analyst extension. Picture rasters are often used as attributes in tables—they can be displayed with your geographic data and are used to convey additional information about map features.
10/8/ 2. Data Structures and Data Models. О “Raster” and “Vector” refer to a particular data model. О A data structure refers to a particular.
In contrast to the raster data model is the vector data model. In this model, space is not quantized into discrete grid cells like the raster model. 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
Distinguish between continuous and categorical raster data and identify types of datasets that would be stored in each format. This episode introduces the two primary types of geospatial data: rasters and vectors. After briefly introducing these data types, this episode focuses on raster data, describing some major features and types of raster data. The two primary types of geospatial data are raster and vector data. Raster data is stored as a grid of values which are rendered on a map as pixels. Vector data structures will be discussed in more detail in the next episode.
Raster is a method for the storage, processing and display of spatial data. Each area is divided into rows and columns, which form a regular grid structure. Each cell must be rectangular in shape, but not necessarily square. Each cell within this matrix contains location co-ordinates as well as an attribute value. The spatial location of each cell is implicitly contained within the ordering of the matrix, unlike a vector structure which stores topology explicitly. Areas containing the same attribute value are recognised as such, however, raster structures cannot identify the boundaries of such areas as polygons.
With regard to representation models, unified data models such as the vector/field model (Winter and Frank ; Kjenstad ), the object field.
Every house, every tree, every city has its own unique latitude and longitude coordinates. The two primary types of spatial data are vector and raster data in GIS. But what is the difference between raster and vector data? When should we use raster and when should we use vector features? Find out more on the spatial data models commonly used.
Structures for Data Compression. General Compression Concepts. Vector Data Storage and Compression. Raster Data Storage and Compression. Raster Data Structure. Raster Data Storage. Raster Data Compression.
Vector data is comprised of lines or arcs, defined by beginning and end points, which meet at nodes.
Живший в ее сознании герой умер, превратился в убийцу. Его руки внезапно снова потянулись к ней в отчаянном порыве. Он целовал ее щеки. - Прости меня, - умолял .
Так в чем же проблема, Фил? - спросил Стратмор, открывая холодильник. - Может, чего-нибудь выпьешь. - Нет, а-а… нет, спасибо, сэр.
Стратмор отпустил створки двери, и тонюсенькая полоска света исчезла. Сьюзан смотрела, как фигура Стратмора растворяется во тьме шифровалки.
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