[GRASS-user] g.region: use of multiple map types

[Rich Shepard]

   In the thread on clipping a large raster map to the interior of a vector
map one recommended syntax was:

 	g.region -a rast=dem_east vect=anal_bndry align=dem_east

and I want to understand what this does. My reading of the man page suggests
that the region will first be set to the raster map, then to the vector map,
with edge alignments to whole cells on the raster map. However, there is no
example on that page of the use of two map types in the command.

   Please clarify how the above syntax sets the region to that of the vector
map so that using r.mapcalc will save only (aligned) raster cells within
that boundary to a new raster map.

Rich