Thanks Uffe,

The example was a great help.
I will probably use the way you mention, although I did find another way
to do it, but which only works over small areas.

lat = latitude of first point
long = longitude of firat point
angle = angle in degrees or radians
dist = distance to go from lat/long in meters

lat1 = lat + (dist * sin(angle) / 111194.6123
long1 = long + (length * cos(angle)) / (111194.6123 * cos((lat + lat1) /
2))

It seems to work

Either way looks good.

Cheers

Tim


-----Original Message-----
From: Uffe Kousgaard [mailto:[EMAIL PROTECTED] 
Sent: 02 July 2004 14:09
To: Mapinfo-L
Subject: Re: MI-L New lat/long from distance/bearing



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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