More than just a resource for visual information, raster data are samples of a given spatial attribute, whose values can be analyzed in order to produce valuable information.
Is this chapter, we will extract information from raster data with special emphasis on statistical information. Following the previous examples, we will use the digital elevation model to obtain values such as the maximum and minimum altitude of a given region, separate altitude ranges into classes, and produce histograms and other statistical information. Going beyond simple numerical values, we will display all the information on beautifully colored maps.
The topics covered by this chapter are:
How to obtain statistics from raster data
The use of programming techniques, such as lazy evaluation and memorization, to avoid unnecessary calculation
How to format tabular data output
How to colorize maps and choose suitable colors for them
How to blend color maps in order to produce...