Geo::Forward - Calculate geographic location from lat, lon, distance, and heading.

NAME

Geo::Forward - Calculate geographic location from lat, lon, distance, and heading.

SYNOPSIS

  use Geo::Forward;
  my $obj = Geo::Forward->new(); # default "WGS84"
  my ($lat1,$lon1,$faz,$dist)=(38.871022, -77.055874, 62.888507083, 4565.6854);
  my ($lat2,$lon2,$baz) = $obj->forward($lat1,$lon1,$faz,$dist);
  print "Input Lat: $lat1  Lon: $lon1\n";
  print "Input Forward Azimuth: $faz\n";
  print "Input Distance: $dist\n";
  print "Output Lat: $lat2 Lon: $lon2\n";
  print "Output Back Azimuth: $baz\n";

DESCRIPTION

This module is a pure Perl port of the NGS program in the public domain ``forward'' by Robert (Sid) Safford and Stephen J. Frakes.

CONSTRUCTOR

new

The new() constructor may be called with any parameter that is appropriate to the ellipsoid method which establishes the ellipsoid.

  my $obj = Geo::Forward->new(); # default "WGS84"

METHODS

ellipsoid

Method to set or retrieve the current ellipsoid object. The ellipsoid is a Geo::Ellipsoids object.

  my $ellipsoid=$obj->ellipsoid;  #Default is WGS84
  $obj->ellipsoid('Clarke 1866'); #Built in ellipsoids from Geo::Ellipsoids
  $obj->ellipsoid({a=>1});        #Custom Sphere 1 unit radius

forward

This method is the user frontend to the mathematics. This interface will not change in future versions.

  my ($lat2,$lon2,$baz) = $obj->forward($lat1,$lon1,$faz,$dist);

TODO

Add tests for more ellipsoids.

BUGS

Please send to the geo-perl email list.

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

Copyright (c) 2006 Michael R. Davis (mrdvt92)

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

 Geo::Forward - Calculate geographic location from lat, lon, distance, and heading.