NAME

GIS::Distance::GreatCircle - Great circle distance calculations.

SYNOPSIS

my $calc = GIS::Distance::GreatCircle->new();
my $distance = $calc->distance( $lon1, $lat1 => $lon2, $lat2 );

DESCRIPTION

FORMULA

c = 2 * asin( sqrt(
  ( sin(( lat1 - lat2 )/2) )^2 + 
  cos( lat1 ) * cos( lat2 ) * 
  ( sin(( lon1 - lon2 )/2) )^2
) )

AUTHOR

Aran Clary Deltac <bluefeet@cpan.org>

LICENSE

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.