NAME
Geo::Inverse - Calculate geographic distance from a lat & lon pair.
SYNOPSIS
use Geo::Inverse;
my $obj = Geo::Inverse->new(); # default "WGS84"
my ($lat1,$lon1,$lat2,$lon2)=(38.87, -77.05, 38.95, -77.23);
my ($faz, $baz, $dist)=$obj->inverse($lat1,$lon1,$lat2,$lon2);
print "Input Lat: $lat1 Lon: $lon1\n";
print "Input Lat: $lat2 Lon: $lon2\n";
print "Output Distance: $dist\n";
print "Output Forward Azimuth: $faz\n";
print "Output Back Azimuth: $baz\n";DESCRIPTION
This module is a pure Perl port of the NGS program in the public domain "inverse" by Robert (Sid) Safford and Stephen J. Frakes.
CONSTRUCTOR
new
The new() constructor may be called with any parameter that is appropriate to the Geo::Ellipsoids->new() constructor which established the ellipsoid.
my $obj = Geo::Inverse->new(); # default "WGS84"
METHODS
set
Method sets the current ellipsoid. This method is called when the object is constructed (default is WGS84).
$obj->set(); #default WGS84
$obj->set('Clarke 1866'); #Built in ellipsoids from Geo::Ellipsoids
$obj->set({a=>1}); #Custom Sphere 1 unit radiusellipsoid
Method to set or retrieve the current ellipsoid object the ellipsoid oject does not have to be Geo::Ellipsoids but it must be blessed and know $obj->a and $obj->f methods.
inverse
This method is the user frontend to the mathematics. This interface will not change in future versions.
my ($faz, $baz, $dist)=$obj->inverse($lat1,$lon1,$lat2,$lon2);TODO
Add more tests.
BUGS
LIMITS
No guarantees that Perl handles all of the double precision calculations in the same manner as Fortran.
AUTHOR
Michael R. Davis qw/perl michaelrdavis com/
LICENSE
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
SEE ALSO
Net::GPSD Geo::Spline Geo::Ellipsoid Geo::Ellipsoids