[R-sig-Geo] MGRS conversion

[Roger Bivand]

On Fri, 8 Jan 2010, Dan Putler wrote:

> Hi Nils,
>
> Likely via the spTransform function in the rgdal package.
>

But I believe a user-written wrapper would be needed to translate MGRS 
first to +proj=utm with zone number, or Universal Polar Stereographic near 
Poles, 100km square IDs, etc. Scanning the PROJ.4 list suggests that 
nobody has done this. In addition, the real authorities have left little 
doubt that MGRS is a very bad idea if used outside its originating context 
(easy errors, UTM zone transition problems, etc) - see the PROJ.4 list 
archives for May 2006 for a taste:

http://lists.maptools.org/pipermail/proj/2006-May/002216.html

http://lists.maptools.org/pipermail/proj/2006-May/002235.html

So that's why it isn't there, with the motivation. Thw wikipedia page 
gives enough details for a simple hack in some places, but if you can 
source the data in a "real" coordinate reference system, you would be 
on a much sounder footing.

Hope this helps,

Roger

> Dan
>
> On Fri, 2010-01-08 at 13:40 -0500, Nils B. Weidmann wrote:
>> Hi all,
>>
>> is there a way to convert Military Grid (MGRS) coordinates to lat/long
>> using R's spatial packages? Thanks for any advice you may have!
>>
>> Best
>> Nils
>

-- 
Roger Bivand
Economic Geography Section, Department of Economics, Norwegian School of
Economics and Business Administration, Helleveien 30, N-5045 Bergen,
Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43
e-mail: Roger.Bivand at nhh.no