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- https://geo.libretexts.org/Bookshelves/Geography_(Physical)/Essentials_of_Geographic_Information_Systems_(Campbell_and_Shin)/09%3A_Cartographic_Principles/9.03%3A_Cartographic_DesignIn addition to effective use of colors and symbols, a map that is well designed will greatly enhance its ability to relate pertinent spatial information to the viewer. Judicious use of map elements, t...In addition to effective use of colors and symbols, a map that is well designed will greatly enhance its ability to relate pertinent spatial information to the viewer. Judicious use of map elements, typography/labels, and design principles will result in maps that minimize confusion and maximize interpretability. Furthermore, the use of these components must be guided by a keen understanding of the map’s purpose, intended audience, topic, scale, and production/reproduction method.
- https://geo.libretexts.org/Bookshelves/Geography_(Physical)/Essentials_of_Geographic_Information_Systems_(Campbell_and_Shin)/08%3A_Geospatial_Analysis_II-_Raster_DataFollowing our discussion of attribute and vector data analysis, raster data analysis presents the final powerful data mining tool available to geographers. Raster data are particularly suited to certa...Following our discussion of attribute and vector data analysis, raster data analysis presents the final powerful data mining tool available to geographers. Raster data are particularly suited to certain types of analyses, such as basic geoprocessing, surface analysis, and terrain mapping. While not always true, raster data can simplify many types of spatial analyses that would otherwise be overly cumbersome to perform on vector datasets.
- https://geo.libretexts.org/Bookshelves/Geography_(Physical)/Essentials_of_Geographic_Information_Systems_(Campbell_and_Shin)/02%3A_Map_Anatomy/2.03%3A_Map_AbstractionImage maps now provide geographic context for nightly news stories around the world, serve as a backdrop to local real estate searches and driving directions, and are also used for research purposes ....Image maps now provide geographic context for nightly news stories around the world, serve as a backdrop to local real estate searches and driving directions, and are also used for research purposes . The popularity and widespread use of such images speaks not only to recent technological advances and innovations but also, perhaps more important, to the geographer in us all.
- https://geo.libretexts.org/Bookshelves/Geography_(Physical)/Essentials_of_Geographic_Information_Systems_(Campbell_and_Shin)/05%3A_Geospatial_Data_Management/5.04%3A_Data_QualityFor example, the definition of a wetland boundary for the riverine wetlands in the eastern United States, where water is abundant, is often useless when delineating similar types of wetlands in the de...For example, the definition of a wetland boundary for the riverine wetlands in the eastern United States, where water is abundant, is often useless when delineating similar types of wetlands in the desert southwest United States. Indeed, the complexity and confusion associated with the conception of what a “wetland” is may result in difficulties defining the feature in the field, which subsequently leads to positional accuracy errors in the GIS database.
- https://geo.libretexts.org/Bookshelves/Geography_(Physical)/Essentials_of_Geographic_Information_Systems_(Campbell_and_Shin)/07%3A_Geospatial_Analysis_I-_Vector_OperationsPreviously. we discussed different ways to query, classify, and summarize information in attribute tables. They don’t take particular advantage of the greatest strength of a geographic information sys...Previously. we discussed different ways to query, classify, and summarize information in attribute tables. They don’t take particular advantage of the greatest strength of a geographic information system (GIS), notably the explicit spatial relationships. Spatial analysis is a fundamental component of a GIS that allows for an in-depth study of the topological and geometric properties of a dataset or datasets. In this chapter, we discuss the basic spatial analysis techniques for vector datasets.
- https://geo.libretexts.org/Bookshelves/Geography_(Physical)/Essentials_of_Geographic_Information_Systems_(Campbell_and_Shin)/08%3A_Geospatial_Analysis_II-_Raster_Data/8.02%3A_Scale_of_AnalysisFor example, the minimum, maximum, average, range, and so forth can be quickly calculated over the entire extent of the input raster and subsequently be output to a raster in which every cell contains...For example, the minimum, maximum, average, range, and so forth can be quickly calculated over the entire extent of the input raster and subsequently be output to a raster in which every cell contains that calculated value (Figure 8.8).
- https://geo.libretexts.org/Bookshelves/Geography_(Physical)/Essentials_of_Geographic_Information_Systems_(Campbell_and_Shin)/08%3A_Geospatial_Analysis_II-_Raster_Data/8.01%3A_Basic_Geoprocessing_with_RastersMost geographic information system (GIS) programs calculate raster buffers by creating a grid of distance values from the center of the target cell(s) to the center of the neighboring cells and then r...Most geographic information system (GIS) programs calculate raster buffers by creating a grid of distance values from the center of the target cell(s) to the center of the neighboring cells and then reclassifying those distances such that a “1” represents those cells composing the original target, a “2” represents those cells within the user-defined buffer area, and a “0” represents those cells outside of the target and buffer areas.
- https://geo.libretexts.org/Bookshelves/Geography_(Physical)/Essentials_of_Geographic_Information_Systems_(Campbell_and_Shin)/03%3A_Data_Information_and_Where_to_Find_Them/3.02%3A_Data_about_DataThese metadata files contain items such as general descriptions about the contents of the file, definitions for the various terms used to identify records (rows) and fields (fields), the range of valu...These metadata files contain items such as general descriptions about the contents of the file, definitions for the various terms used to identify records (rows) and fields (fields), the range of values for fields, the quality or reliability of the data and measurements, how the data were collected, when the data were collected, and who collected the data.
- https://geo.libretexts.org/Bookshelves/Geography_(Physical)/Essentials_of_Geographic_Information_Systems_(Campbell_and_Shin)/04%3A_Data_Models_for_GIS/4.02%3A_Vector_Data_ModelsIn comparison with the raster data model, vector data models tend to be better representations of reality due to the accuracy and precision of points, lines, and polygons over the regularly spaced gri...In comparison with the raster data model, vector data models tend to be better representations of reality due to the accuracy and precision of points, lines, and polygons over the regularly spaced grid cells of the raster model.
- https://geo.libretexts.org/Bookshelves/Geography_(Physical)/Essentials_of_Geographic_Information_Systems_(Campbell_and_Shin)/07%3A_Geospatial_Analysis_I-_Vector_Operations/7.02%3A_Multiple_Layer_AnalysisIn addition to these simple operations, the identity (also referred to as “minus”) overlay method creates an output layer with the spatial extent of the input layer (part (d) of Figure 7.11) but inclu...In addition to these simple operations, the identity (also referred to as “minus”) overlay method creates an output layer with the spatial extent of the input layer (part (d) of Figure 7.11) but includes attribute information from the overlay (referred to as the “identity” layer, in this case).
- https://geo.libretexts.org/Bookshelves/Geography_(Physical)/Essentials_of_Geographic_Information_Systems_(Campbell_and_Shin)/zz%3A_Back_Matter/20%3A_GlossaryA floating-point data value occupying 64 bits, characterized by up to 11 bits to the left of the decimal and up to 52 bit values to the right of the decimal point. An operation that appends the inform...A floating-point data value occupying 64 bits, characterized by up to 11 bits to the left of the decimal and up to 52 bit values to the right of the decimal point. An operation that appends the information of one table into a second table through the use of an attribute or field that is common to both tables. A manual data capture method whereby a user enters coordinate information into a computer through the use of a digitizing tablet and a digitizing puck.
