From: "Tim Smith" <[EMAIL PROTECTED]>

<snip>
What I need to be able to do is convert from my position in degrees to a
meter system.
</snip>

If you want to do that, you will find the formulas here
(http://www.gpsy.com/gpsinfo/geotoutm/), but it is much more complicated
than doing the calculations, I suggested:

lat1 = 50.9051 degrees = 50.9051 / 180 * pi radians = 0.88846 radians
lon1 = -1.0649 degrees = -0.018586 radians
tc = 45 degrees = 0.785398 radians
d = 500m = 500 m / 6378130 m = 0.000078392 radians

lat=asin(sin(lat1)*cos(d)+cos(lat1)*sin(d)*cos(tc))
IF (cos(lat)=0)
  lon=lon1      // endpoint a pole
ELSE
  lon=mod(lon1-asin(sin(tc)*sin(d)/cos(lat))+pi,2*pi)-pi
ENDIF

I get these values as result:
lat = 50.908275919285
lon = -1.06993680690127

Now I entered these 2 points into a TAB file and measured the distance
and get 500 meter as expected.

Kind regards

Uffe Kousgaard
www.routeware.dk


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