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"Erroneous" is relative to your accuracy needs. Let us therefore estimate the accuracy in terms of the distance the boat has traveled: by means of such a result, you can decide when positional calculations become "erroneous." I understand the question as saying that mapping is carried out in an azimuthal equidistant coordinate system centered at the boat's ...


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It is due to the projection of a 2D plane onto a polorised 2 spheres surface, as the line moves past the poles, it becomes distorted as far as observers of the 2D plane are concerned because the straight line to the destination appears to be a curved ark of a Great Circle, which is a term in mathematics that relates to the greatest circle that can be sliced ...


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I got this working in ObjectiveC. The key here is knowing that you need lat/lng points in radians and you need to convert them back to lat/lng after applying the equation. Also, know that distance and tc are in radians. Here's the original equation: lat=asin(sin(lat1)*cos(d)+cos(lat1)*sin(d)*cos(tc)) IF (cos(lat)=0) lon=lon1 // endpoint a pole ...


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Here is a Python solution: def displace(self, theta, distance): """ Displace a LatLng theta degrees counterclockwise and some meters in that direction. Notes: http://www.movable-type.co.uk/scripts/latlong.html 0 DEGREES IS THE VERTICAL Y AXIS! IMPORTANT! Args: theta: A number in degrees. distance: A ...


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Yes, if you want ST_Area() on a bare geometry to return a planar area, you need to use an area-preserving CRS. GEOS is not magic, it just works in whatever units are handed to it, assuming cartesian math, so the expectation in a planar CRS if you want useful areas/lengths etc.



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