[GRASS-user] Correcting A Map's Region

[Michael Barton]

Rich,

Since the region is a function of the mapset, not the map, what you need to do is to expand the region (computational or display) to include the map. You cannot change the 'map region' as it does not exist. Think of the region as a sort of window on the world. Your map may or may not be in the part of the world exposed by that window. If not, you need to change where the window looks not the the map.

The map does have a geospatial location, whose extents you can find by doing r.info map=[mapname]. To display the map, you need to change your region extents to encompass the map. If you want to see several maps in different geographic locations, you need to have a region big enough to encompass all their extents. 

If you discover, when you expand your region to a size that encompasses the extents of all maps, that one map is 'misplaced' geographically, then you need to reimport or reposition the map geographically (i.e., with respect to its georeferencing). For a vector, you can shift it using v.proj. Shifting a raster is harder. I think it is doable, but I can't think of how to do it right now. 

Hope this helps

Michael
____________________
C. Michael Barton
Director, Center for Social Dynamics & Complexity 
Professor of Anthropology, School of Human Evolution & Social Change
Arizona State University

voice: 	480-965-6262 (SHESC), 480-727-9746 (CSDC)
fax:          480-965-7671 (SHESC),  480-727-0709 (CSDC)
www: http://www.public.asu.edu/~cmbarton, http://csdc.asu.edu





On Aug 25, 2011, at 4:15 AM, <grass-user-request at lists.osgeo.org> <grass-user-request at lists.osgeo.org> wrote:

> Date: Wed, 24 Aug 2011 13:43:21 -0700 (PDT)
> From: Rich Shepard <rshepard at appl-ecosys.com>
> Subject: Re: [GRASS-user] Correcting A Map's Region
> To: grass-users at lists.osgeo.org
> Message-ID: <alpine.LNX.2.00.1108241339540.9821 at salmo.appl-ecosys.com>
> Content-Type: TEXT/PLAIN; charset=UTF-8; format=flowed
> 
> On Wed, 24 Aug 2011, Micha Silver wrote:
> 
>> The region is part of the mapset, NOT the vector (or raster for that matter). ??
> 
>   Let me try this again:
> 
>   First, I set the region to the desired one (called 'basin' for this part
> of the project), then I try to display the proj_pts map in it:
> 
> GRASS 6.5.svn (Oregon):~/grassdata > g.region region=basin
> GRASS 6.5.svn (Oregon):~/grassdata > d.mon start=x0
> using default visual which is TrueColor
> ncolors: 16777216
> Graphics driver [x0] started
> GRASS 6.5.svn (Oregon):~/grassdata > d.vect map=proj_pts
> The bounding box of the map is outside the current region, nothing drawn.
> GRASS 6.5.svn (Oregon):~/grassdata >
> 
>   All in the same location and mapset.
> 
> Rich