[GRASSLIST:1661] Re: Combining data from several locations

[Morten Hulden]

On Thu, 22 Mar 2001, Artemis wrote:

> Hi all,
> 
> Some time ago I created several different
> UTM locations, depending on the scale of
> the scanned maps. Now I have the locations
> called e.g. 1-500.000 and 1-200.000. Now
> I have to create a totally new location
> with possibly different scale, containing
> the data from two previous ones, selected
> by some boundaries.

You really do not have to create different locations for the same area if
the maps only differ in resolution. Create one single area covering the
largest map, and set the default resolution to correspond to the map with
the best resolution. Then within that location you can create 'named
regions' that differ from the default region in coverage or in resolution,
or both. You can use g.region to switch between named regions, or d.zoom
to zoom in the monitor window.

When you import new maps, with r.proj of one of the r.in -tools, first
create a new region or set the current region so that it corresponds to
the coverage (or area of interest) and resolution of the input map. That
way your maps will not become unnecessarily large, and import time will be
shorter. All your maps can co-exist in the same location, as long as the
projection is the same, and the maps cover the same geographic area.

regards
Morten Hulden