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GIS::Distance::ALT - Andoyer-Lambert-Thomas distance calculations.


The ALT formula is intended as a much faster, but slightly less accurate, alternative of the GIS::Distance::Vincenty formula. This formulas is about 5x faster than Vincenty.

The code for this formula was taken from Geo::Distance::XS and modified to fit.

A faster (XS) version of this formula is available as GIS::Distance::Fast::ALT.

Normally this module is not used directly. Instead GIS::Distance is used which in turn interfaces with the various formula classes.


See "SUPPORT" in GIS::Distance.


See "AUTHORS" in GIS::Distance.


See "LICENSE" in GIS::Distance.