[GRASS-user] Reprojecting Vector Map

[Rich Shepard]

On Tue, 24 Nov 2009, Pablo Carreira wrote:

> Assumptions:
> -Very well defined LOCATION parameters is the foundation to perfectly combine maps of different sources.
> -The experience tells me that some data are even in the correct reference system, but sometimes the "info" that comes with it sometimes not.
> -Each coutry has it's adequated reference system.
> -GIS and GPS comes with a lot of reference systems, but they follow an international standard.
> -Those standards sometimes differ a little from the "real parameters".

Pablo,

   Thanks for your contributions. I think that I have this correctly handled
now.

   My raster (DEM) layer covers the northwest portion of the state, the
hydrologic unit boundaries (level 6) and dams are statewide. These three are
lcc projection. Soils and streets are for a specific county. The former is
UTM Zone 10, the latter lat/long.

   The soils data are in .e00 format, but without the projection/datum
information in the header.

   The wxPython GUI has a bug: when UTM is specified as the projection, we
cannot change the zone from the default 30. The Tcl/Tk GUI didn't ask me to
specify a projection. I commented out most lines in ~/.grassrc6 and worked
in the original, ugly, user-unfriendly VT100 interface. With numerous errors
and use of the arrow keys I was able to enter all relevant information
except for the e-w and n-s resolutions. The metadata file specifies those as
0 but GRASS64svn won't take that value. I had to use 1 instead. Shrug.

   Once I had the soils/PERMANENT location defined I exited grass, restored
the rc file, and restarted it. Using the wxPython UI I defined the mapset
and imported the mapping unit areas, line features, and point features.

   Then I created a new location and defined it as LCC. From within that new
location I ran v.proj and converted the three soils layers. 'g.region -p'
appears to display correct coordinates.

   Now I need to re-do the streets and see if I can get that layer
reprojected from LL to LCC. So far it's fighting me and winning.

Rich