![]() Fuzzy logic assigns membership values (out of 1) that indicate the possibility and probability that a site will be suitable. This should not be used when the location cannot be controlled (i.e. Weighted site selection allows one to assign and/or rank relative importance to each data layer resulting in a range of least to most suitable sites and areas. Binary site selection results in a clear yes/no conclusion for site suitability. The benefit of using raster is the ability to use weighted or fuzzy logic tools in addition to the analysis that is possible with vector data. This can be performed using both vector and raster data. Raster data can be found in various image formats (TIFF, JPEG, IMG, GRID, etc.) However, JPEG and TIFF are the most widely supported, used for a variety of data types and work well with color, black and white and gray scale images.Īnalysis Procedures: Using GIS and analysis tool determining the most suitable area for a purpose or particular analysis is referred to as site selection or suitability analysis. For example, a DEM has 1 band, whereas a aerial photo in color may have 3 bands. A raster dataset may be composed of one or more bands. If the display scale of two images is the same/similar, but the cell size differs, the image with the smaller cell size will display greater detail and appear to provide a more thorough conclusion. An example of this is a display scale of 1:10,000 has less detail than a display scale of 1:5000. Scale refers to the level of detail displayed. The spatial resolution required depends on the type and scale of analysis, accuracy of the study and limitations such as time and data size. Spatial resolution refers to the cell size and determines the level of detail that will be included within the raster display. Raster data is composed of cells in a grid like structure. ![]() Raster data can be stored in various formats including DEM's (Digital Elevation Models), USGS, ESRI Grids, and image formats including JPEG, TIFF, IMG and GIF. Rasters can also be digital or scanned documents that can be used as attributes of a feature collected from a variety of sources such as aerial photography, satellite sensors, scanning maps, surveying, and from converting vector to raster data. Raster data tends to typically provide greater details, has a larger data volume and allows for more advanced analyses than vector data. These data models complement each other but can be converted if necessary using various conversion tools. Vector models serve as the other primary dataset used in ArcGIS. Vector data modelsrepresent discrete points, line and polygons that are not continuous in nature. The smaller the cell size, the greater the resolution and file size of the raster. temperature, elevation, land-use, soil type). The simplest modeling is score based modeling using “weighted sum” concept.Problem: Conversion techniques of vector data to raster data.Īnalysis Procedures: Raster data is a field based data model that represents geography as a continuum though using grid cells that store attribute values, but can also be used as discrete thematic rasters (i.e. You can use the map as one of factors of modeling. The original slope(continuous value) map has been converted to a categorical slope map!! Result. ![]() 15 Raster analysis > Reclassify by table > Change settings like below > Run Settings The example of Range boundaries Check the resultĬhange the color settings to unique color using the new value. The map is colored by slope categories(e.g. In this tutorial, we are going to use the below slope map. This process is very important to create a potential map(suitable map, probability map, etc.). categorical raster based on a slope, elevation etc.) or managing a category, reclassify function is key. When you create a categorical data from a continuous value data(e.g. ![]()
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