[GRASS-windows] v.in.ogr, other questions also

[Markus Neteler]

On Mon, Jan 5, 2009 at 5:39 PM, Monkey Boy <slabshaft at gmail.com> wrote:
> More questions about inputting vector data, and viewing the maps.
>
> I just read in a .shp file and the Output window said stuff was imported and
> "topology was built"....

Good: the map was imported!

> When I added my newly created vector output map, I was told "The bounding
> box of the map is outside the current region, nothing drawn".  I went to the
> Map Display window and zoomed out a bunch, then refit the zoom to the
> selected map, which then made my map visible.
>
> Question:
> Is there a way to make the "bounding box" automatically zoom to the selected
> map?

Either with g.region as indicated in the other followup mail or in gis.m

http://grass.osgeo.org/grass64/manuals/html64_user/gis.m.html
-> MAP DISPLAY BUTTON FUNCTIONS
  -> Zoom menu
    -> Zoom to match the extents of a selected map

> Does this have something to do with the "Starting Location" specified
> on the GRASS startup screen?

Yes and no. The "Starting Location" *should* be defined wide enough to
cover you map but you can expand on the fly during import. Or even
ignore that and always set the current region to the map.

> Other questions:
> Is the elevation data automatically contained within the .shp, .shx, and
> .dbf files, or do I have to assign elevations to individual contour lines?
> (this is probably a stupid question, I've still a lot to learn about this
> stuff...)

elevation data is typically not delivered in SHAPE format but in GeoTIFF
format. If someone gives elevation data to you in SHAPE format it
will be either point data or contour lines, to get a raster surface map
you need to interpolate (GRASS offers various algorithms for that,
see
 http://grass.osgeo.org/grass64/manuals/html64_user/rasterintro.html
 -> Resampling methods and interpolation methods

> Is it possible to create elevation profiles from vector maps or does the
> data have to be converted into raster maps?

v.to.db can do a lot
http://grass.osgeo.org/grass64/manuals/html64_user/v.to.db.html
but it depends on the vector data structure. Typically raster model
is use with elevation data.

> How do I define a new "Project Location (projection/coordinate system)" on
> the Startup screen?  (this question is probably too general, I'm just
> fishing for more info about how these are defined and how GRASS recognizes a
> valid location to start using)

See
 http://grass.osgeo.org/grass64/manuals/html64_user/helptext.html
for defining a location.

In GRASS 6.4.x there is a new GUI which offers a cool Location wizard:
http://grass.osgeo.org/screenshots/gui.php#wxpython
 -> Location wizard

It should be made available soon (hopefully with all portability issues
fixed).

Hope this helps,
Markus

-- 
Open Source Geospatial Foundation
http://www.osgeo.org/
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