Re: polygonal area on a sphere

If your polygon is small enough to allow you to ignore the Earth's
curvature, you can use the following formula. You need to convert
lat/lon to x-y coordinates. If the polygon lies within one UTM region,
you can just convert lat/lon to UTM and use the UTM coordinates.

area = sum_{i=0}^{n-1} ((x_i + x_{i+1}) (y_{i+1} - y_i)) / 2
where point 0 = point N.

Is there a general formula in case of the area is between two UTM
regions?


.

Relevant Pages

  • Re: polygonal area on a sphere
    ... lat/lon to x-y coordinates. ... If the polygon lies within one UTM region, ... you can just convert lat/lon to UTM and use the UTM coordinates. ...
    (sci.geo.satellite-nav)
  • Re: polygonal area on a sphere
    ... lat/lon to x-y coordinates. ... you can just convert lat/lon to UTM and use the UTM coordinates. ... If the point is near to another region you can often use UTM values for one region by extending the values into the second region. ...
    (sci.geo.satellite-nav)
  • Re: polygonal area on a sphere
    ... If your polygon is small enough to allow you to ignore the Earth's curvature, you can use the following formula. ... You need to convert lat/lon to x-y coordinates. ... If the polygon lies within one UTM region, you can just convert lat/lon to UTM and use the UTM coordinates. ...
    (sci.geo.satellite-nav)
  • Re: Terraserver, GPX data, and me
    ... couple of php functions that will convert utm to lat/lon and lat/lon ... Thanks for everyones help and patience here! ...
    (sci.geo.satellite-nav)
  • Re: Lat/long for 6th graders
    ... introduction to UTM or whatever grid reference system you find in your ... local street directories. ... don't see it, the local grid coordinates (AUS 66, UTM). ... lat/lon. ...
    (sci.geo.satellite-nav)