ITRF (International Terrestrial Reference Frame) Coordinate

class satkit.itrfcoord(*args, **kwargs)

Representation of a coordinate in the International Terrestrial Reference Frame (ITRF)

Notes:

This coordinate object can be created from and also output to Geodetic coordinates (latitude, longitude, height above ellipsoid).
Functions are also available to provide rotation quaternions to the East-North-Up frame and North-East-Down frame at this coordinate

Parameters:

vec (numpy.ndarray, list, or 3-element tuple of floats, optional) – ITRF Cartesian location in meters
latitude_deg (float, optional) – Latitude in degrees
longitude_deg (float, optional) – Longitude in degrees
latitude_rad (float, optional) – Latitude in radians
longitude_rad (float, optional) – Longitude in radians
altitude (float, optional) – Height above ellipsoid, meters
height (float, optional) – Height above ellipsoid, meters

Returns:

New ITRF coordinate

Return type:

itrfcoord

Example

Create ITRF coord from Cartesian

>>> coord = itrfcoord([ 1523128.63570828 -4461395.28873207  4281865.94218203 ])
>>> print(coord)
ITRFCoord(lat:  42.4400 deg, lon: -71.1500 deg, hae:  0.10 km)

Create ITRF coord from Geodetic

>>> coord = itrfcoord(latitude_deg=42.44, longitude_deg=-71.15, altitude=100)
>>> print(coord)
ITRFCoord(lat:  42.4400 deg, lon: -71.1500 deg, hae:  0.10 km)

property altitude: Altitude above ellipsoid, in meters

geodesic_distance(other: itrfcoord)

Use Vincenty formula to compute geodesic distance: https://en.wikipedia.org/wiki/Vincenty%27s_formulae

Returns:: (distance in meters, initial heading in radians, heading at destination in radians)
Return type:: tuple[float, float, float]

property geodetic_deg

Geodetic position in degrees

Returns:: Tuple with 3 elements representing the geodetic position. First element is latitude in degrees, second is longitude in degrees, and third is altitude in meters
Return type:: tuple[float, float, float]

property geodetic_rad

Geodetic position in radians

Returns:: Tuple with 3 elements representing the geodetic position. First element is latitude in radians, second is longitude in radians, and third is altitude in meters
Return type:: tuple[float, float, float]

property latitude_deg: Latitude in degrees

property latitude_rad: Latitude in radians

property longitude_deg: Longitude in degrees

property longitude_rad: Longitude in radians

move_with_heading(distance: float, heading_rad: float)

Move a distance along the Earth surface with a given initial heading

Parameters:

distance (float) – Distance to move in meters
heading_rad (float) – Initial heading in radians

Notes

Altitude is assumed to be zero

Use Vincenty formula to compute position: https://en.wikipedia.org/wiki/Vincenty%27s_formulae

Returns:: (distance in meters, initial heading in radians, heading at destination in radians)
Return type:: tuple[float, float, float]

property qenu2itrf

Quaternion representiong rotation from East-North-Up (ENU) to ITRF at this location

Returns:: Quaternion representiong rotation from East-North-Up (ENU) to ITRF at this location
Return type:: satkit.quaternion

property qned2itrf

Quaternion representing rotation from North-East-Down (NED) to ITRF at this location

Returns:: Quaternion representiong rotation from North-East-Down (NED) to ITRF at this location
Return type:: satkit.quaternion

property vector

Cartesian ITRF coord as numpy array

Returns:: 3-element numpy array representing the ITRF Cartesian coordinate in meters
Return type:: npt.NDArray[np.float64]