Package pygeodesy :: Module ecef
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Module ecef

Geocentric conversions transcribed from Charles Karney's C++ classes Geocentric and LocalCartesian into pure Python classes EcefKarney respectively EcefCartesian, class EcefSudano based on John Sudano's paper, class EcefVeness transcribed from Chris Veness' JavaScript classes LatLonEllipsoidal, Cartesian and class EcefYou implementing Rey-Jer You's transformations.

Convert between geodetic coordinates lat-, longitude and height h (measured vertically from the surface of the ellipsoid) to geocentric x, y and z coordinates, also known as Earth-Centered, Earth-Fixed (ECEF).

The origin of geocentric coordinates is at the center of the earth. The z axis goes thru the North pole, lat = 90°. The x axis goes thru lat = 0°, lon = 0°.

The local cartesian origin is at (lat0, lon0, height0). The z axis is normal to the ellipsoid, the y axis points due North. The plane z = -height0 is tangent to the ellipsoid.

Forward conversion from geodetic to geocentric (ECEF) coordinates is straightforward.

For the reverse transformation we use Hugues Vermeille's Direct transformation from geocentric coordinates to geodetic coordinates, J. Geodesy (2002) 76, 451-454.

Several changes have been made to ensure that the method returns accurate results for all finite inputs (even if h is infinite). The changes are described in Appendix B of C. F. F. Karney Geodesics on an ellipsoid of revolution, Feb. 2011, 85, 105-117 (preprint). Vermeille similarly updated his method in An analytical method to transform geocentric into geodetic coordinates, J. Geodesy (2011) 85, 105-117. See Geocentric coordinates for more information.

The errors in these routines are close to round-off. Specifically, for points within 5,000 km of the surface of the ellipsoid (either inside or outside the ellipsoid), the error is bounded by 7 nm (7 nanometers) for the WGS84 ellipsoid. See Geocentric coordinates for further information on the errors.


Version: 20.10.11

Classes
  EcefError
An ECEF or Ecef* related issue.
  _EcefBase
(INTERNAL) Base class for EcefKarney, EcefVeness and EcefYou.
  EcefKarney
Conversion between geodetic and geocentric, aka Earth-Centered, Earth-Fixed (ECEF) coordinates based on Karney's Geocentric methods.
  EcefCartesian
Conversion between geodetic (lat, lon, height) and local cartesian (x, y, z) coordinates with a local cartesian origin at (lat0, lon0, height0), transcribed from Karney's C++ class LocalCartesian.
  EcefMatrix
A rotation matrix.
  Ecef9Tuple
9-Tuple (x, y, z, lat, lon, height, C, M, datum) with geocentric coordinates x, y and z, geodetic coordinates lat, lon and height, case C (see the Ecef*.reverse methods) and optionally, the EcefMatrix M and datum, with lat and lon in degrees and x, y, z and height in meter, conventionally.
  EcefVeness
Conversion between geodetic and geocentric, aka Earth-Centered, Earth-Fixed (ECEF) coordinates transcribed from Chris Veness' JavaScript classes LatLonEllipsoidal, Cartesian.
  EcefSudano
Conversion between geodetic and geocentric, aka Earth-Centered, Earth-Fixed (ECEF) coordinates based on John J. Sudano's paper.
  EcefYou
Conversion between geodetic and geocentric, aka Earth-Centered, Earth-Fixed (ECEF) coordinates using Rey-Jer You's transformations.
Variables
  __all__ = _ALL_LAZY.ecef