Getting the Most Out of QGIS and GRASS Integration - Desktop GIS: Mapping the Planet with Open Source Tools - page 222

Figure 12.16: Mapcalc model for converting DEM from meters to feet

are eighteen operators (arithmetic and logical) and thirty-two functions,
including trigonometric, logical, log, and others. So, you can get a lot
fancier than we did with the r.mapcalc module.

12.4 Summing It Up

That concludes our tour of the QGIS-GRASS plugin and toolbox. As you
may have guessed, we just scratched the surface here. It's up to you to
explore further and see what other magic awaits you. As I said at the
beginning of this chapter, we're bordering on advanced territory here.
Keep in mind as you explore the QGIS-GRASS modules that there may
be extra options and “power” available from the GRASS shell.