Package pygeodesy :: Module ellipsoidalVincenty |
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# Module ellipsoidalVincenty

Vincenty's geodetic (lat-/longitude) LatLon, geocentric (ECEF) Cartesian amd VincentyError classes and functions areaOf and perimeterOf, all ellipsoidal.

Pure Python implementation of geodesy tools for ellipsoidal earth models, transcribed from JavaScript originals by (C) Chris Veness 2005-2016 and published under the same MIT Licence**, see Vincenty geodesics. More at GeographicLib and GeoPy.

Calculate geodesic distance between two points using the Vincenty formulae and one of several ellipsoidal earth models. The default model is WGS-84, the most accurate and widely used globally-applicable model for the earth ellipsoid.

Other ellipsoids offering a better fit to the local geoid include Airy (1830) in the UK, Clarke (1880) in Africa, International 1924 in much of Europe, and GRS-67 in South America. North America (NAD83) and Australia (GDA) use GRS-80, which is equivalent to the WGS-84 model.

Great-circle distance uses a spherical model of the earth with the mean earth radius defined by the International Union of Geodesy and Geophysics (IUGG) as (2 * a + b) / 3 = 6371008.7714150598 meter or approx. 6371009 meter (for WGS-84, resulting in an error of up to about 0.5%).

Here's an example usage of `ellipsoidalVincenty`:

    >>> from pygeodesy.ellipsoidalVincenty import LatLon
    >>> Newport_RI = LatLon(41.49008, -71.312796)
    >>> Cleveland_OH = LatLon(41.499498, -81.695391)
    >>> Newport_RI.distanceTo(Cleveland_OH)
    866,455.4329158525  # meter

You can change the ellipsoid model used by the Vincenty formulae as follows:

    >>> from pygeodesy import Datums
    >>> from pygeodesy.ellipsoidalVincenty import LatLon
    >>> p = LatLon(0, 0, datum=Datums.OSGB36)

or by converting to anothor datum:

    >>> p = p.convertDatum(Datums.OSGB36)

Version: 20.02.17

Classes
| VincentyError Error raised from Vincenty's direct and inverse methods for coincident points or lack of convergence.
| Cartesian Extended to convert geocentric, Cartesian points to Vincenty-based, ellipsoidal, geodetic LatLon.
| LatLon Using the formulae devised by Thaddeus Vincenty (1975) with an ellipsoidal model of the earth to compute the geodesic distance and bearings between two given points or the destination point given an start point and initial bearing.

Functions
ispolar(points, wrap=False) Check whether a polygon encloses a pole. |

Function Details

### ispolar(points, wrap=False) |
Check whether a polygon encloses a pole. Parameters: `points` - The polygon points (`LatLon`[]). `wrap` - Wrap and unroll longitudes (`bool`). Returns: `True` if the polygon encloses a pole, `False` otherwise. Raises: `ValueError` - Insufficient number of `points`. `TypeError` - Some `points` are not `LatLon` or don't have `bearingTo2`, `initialBearingTo` and `finalBearingTo` methods.