[Proj] conversion latlong to UTM (& vice versa)

[Roger Oberholtzer]

On Thu, 2006-11-02 at 16:22 +0700, oon at informatika.org wrote:
> Dear All Proj user,
> 
> I want to convert coordinate with datum WGS84, from latlong projection 
> to UTM projection
> (and vice versa).
> 
> If I convert from latlong projection to UTM projection,
> I can get the UTM zone from UTM definition, so I can calculate the zone 
> from it's longitude.
> 
> If I'm doing vehicle tracking with UTM projection,
> and the vehicle moving between UTM zones,
> How should I do to get UTM zone of current position of vehicle?
> (so I can convert UTM to latlong again).
> 
> Is it any statement or definition of UTM that declare
> how to get UTM Zone from UTM coordinate?
> 
> Is it any Proj utilities (function/procedure) that support my problem?

Not exactly an answer here, but we provide locations from moving
vehicles as well. In the countries that are UTM and span more than one
zone, it is quite often the case that one zone is chosen as the one used
in all calcs in the country. In Spain, for example, it is the zone where
Madrid is. In Finland it is Helsinki. In Saudi Arabia it is Riyadh. So,
maybe that is an approach. This is mostly useful for GIS-type apps more
than those wanting to find absolute locations. Of course, all your data
must agree with this.

-- 
Roger Oberholtzer

OPQ Systems AB
Ramböll Sverige AB
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P.O. Box 4205
SE-102 65 Stockholm, Sweden

Tel: Int +46 8-615 60 20
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