...
See also the following external links:
http://pcraster.geoggeo.uu.nl/documentation/pcrman/book1.htmhttp://pcraster.geog.uu.nl/introduction/funclist.htmlPCRaster/html/index.html
http://pcraster.geoggeo.uu.nl/documentation/PCRaster/manual_updateshtml/index.htmlhtml#functional-list-of-applications-and-operations
+ -- Addition
- -- Subtraction
...