Map Algebra
Map Algebra is an analysis
language based loosely on the map algebra concepts presented by Dr. Dana Tomlin
in his book entitled Geographic Information Systems and Cartographic
Modeling (Tomlin, 1990). Map Algebra is a high-level computational language
used for performing cartographic spatial analysis using raster data.
Simply put, Map Algebra is
math applied to rasters, a practice that's possible
because rasters are geographically referenced arrays
of numbers. If you stack rasters on top of each other
as if they were a mathematical sandwich, you can perform simple arithmetic to
the most sophisticated algorithms with them.
Map Algebra is possible for rasters that share the same coordinate system.