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Geografic-Information-System


			
				
					
						
						
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<h2>NAME</h2>

<em><b>g.setproj</b></em> allows the user to create the PROJ_INFO and the
PROJ_UNITS files to record the projection information associated with a
current location.
<br>

<h2>SYNOPSIS</h2>

<b>g.setproj</b> 

<h2>DESCRIPTION</h2>

Allows a user to create a PROJ_INFO file in the PERMANENT mapset of the 
current location. PROJ_INFO file is used to record the projection information 
associated with the specified mapset. 

<h2>NOTES</h2> 

The user running <em>g.setproj</em> must own the PERMANENT 
mapset and it must be currently selected.
It is highly recommended to run <em>g.setproj</em> after
creating a new location so that conversion programs (such
as <em>v.proj</em>) can be run.

<p>The user will be prompted for the projection name. 
Most projections are supported. The 
<a href="https://proj.org/">PROJ</a> abbreviations for the names are
used with two exceptions, viz. 'll', for latitude / longitude geographic
co-ordinates, and 'stp', for the State Plane Co-ordinate system (used in the
USA).

<p>After the projection name, the user will be asked for a geodetic datum. If 
no datum transformation support is needed, the question may be answered with no,
and no datum will be specified in the PROJ_INFO file. If this is the case
the user must specify the ellipsoid (model of the curvature of the earth) to
be used, otherwise it is determined by the datum being used.

<p>If the datum or ellipsoid required are not 
listed within this program, the user/administrator may add the definition 
to the files datum.table, datumtransform.table and ellipse.table in the
<tt>$GISBASE/etc/proj</tt> directory.

<p>Depending on the projection selected, the user will then be prompted for
the various other parameters required to define it.

<p>
The projections of aea, lcc, merc, leae, leac, and 
tmerc will generate a request to the user for the prime meridian and standard 
parallel for the output map. 

<h2>SEE ALSO</h2>

<em><a href="g.proj.html">g.proj</a></em>,
<em><a href="m.proj.html">m.proj</a></em>,
<em><a href="r.proj.html">r.proj</a></em>,
<em><a href="v.proj.html">v.proj</a></em>,
<em><a href="https://proj.org">PROJ</a> site</em>

<p><b>Further reading</b>
<ul>
<li> A guide to <a href="http://erg.usgs.gov/isb/pubs/MapProjections/projections.html">Map Projections</a> by USGS
<li> <a href="https://www.asprs.org/asprs-publications/grids-and-datums">ASPRS Grids and Datum</a>
<li> <a href="http://www.mapref.org">MapRef - The Collection of Map Projections and Reference Systems for Europe</a>
<li> <a href="http://geotiff.maptools.org/proj_list/">Projections Transform List</a> (PROJ)
</ul>

<h2>AUTHORS</h2>

Irina Kosinovsky, 
U.S. Army Construction Engineering 
Research Laboratory<br>
Morten Hulden, morten at untamo.net - rewrote module and added 121 projections <br>
Andreas Lange, andreas.lange at rhein-main.de - added prelimnary map datum support

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