## DESCRIPTION

v.proj allows a user to convert a vector map in a specified mapset of a specified location (different from current) with projection of input location to the vector map in a current mapset of current location with projection of current location (both projections are defined by corresponding PROJ_INFO files).

## NOTES

If output is not specified it is set to be the same as input map name.
If mapset is not specified, its name is assumed to be the same as the current mapset's name.
If dbase is not specified it is assumed to be the current database. The user only has to specify dbase if the source location is stored in another separate GRASS database.

v.proj supports general datum transformations, making use of the PROJ.4 co-ordinate system translation library.

When projecting into a latlon location, east coordinates are wrapped by the proj4 library to fit into the range -180,180. This is in most cases appropriate, but can cause errors the input vector crosses the datum line at 180E/W. In this case wrapping of east coordinates to -180,180 needs to be disabled with the -w flag.

## EXAMPLES

    v.proj in=mymap location=latlong mapset=user1

## REFERENCES

PROJ 4: Projection/datum support library.

Further reading

- ASPRS Grids and Datum
- MapRef - The Collection of Map Projections and Reference Systems for Europe
- Projections Transform List (PROJ4)

## SEE ALSO

r.proj, g.proj, g.setproj, i.rectify, r.stats, v.sample, v.surf.idw, v.surf.rst

## AUTHORS

Irina Kosinovsky, US ARMY CERL
M.L. Holko, USDA, SCS, NHQ-CGIS
R.L. Glenn, USDA, SCS, NHQ-CGIS

Last changed: $Date$