Function navtk::navutils::delta_lon_to_east

Function Documentation

double navtk::navutils::delta_lon_to_east(double delta_lon, double approx_lat, double altitude = 0.0)

Converts small changes of longitude (radians) into distance in meters along the East axis of the local level NED frame.

Input parameters are with respect to the WGS-84 ellipsoid.

This conversion is approximate, and the error grows as the delta_lon grows.

Example:

delta_lon = \(Lon_1 - Lon_0\) (radians)

approx_lat = approximate WGS-84 latitude (radians)

altitude = approximate WGS-84 altitude (meters)

The function will return the approximate distance, in meters, between the points (approx_lat, \(Lon_1\), altitude) and (approx_lat, \(Lon_0\), altitude). The sign of the output matches the sign of the delta_lon input.

See also

delta_lat_to_north()

See also

north_to_delta_lat()

See also

east_to_delta_lon() for the companion function that converts in the opposite direction.

Parameters

  • delta_lon – Small distance in longitude to convert (radians)

  • approx_lat – Approximate latitude (radians)

  • altitude – WGS-84 altitude (ellipsoidal) (meters)

Returns

Equivalent distance (meters).