1Geo::Inverse(3)       User Contributed Perl Documentation      Geo::Inverse(3)
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NAME

6       Geo::Inverse - Calculate geographic distance from a lat & lon pair.
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SYNOPSIS

9         use Geo::Inverse;
10         my $obj = Geo::Inverse->new(); # default "WGS84"
11         my ($lat1,$lon1,$lat2,$lon2)=(38.87, -77.05, 38.95, -77.23);
12         my ($faz, $baz, $dist)=$obj->inverse($lat1,$lon1,$lat2,$lon2); #array context
13         my $dist=$obj->inverse($lat1,$lon1,$lat2,$lon2);              #scalar context
14         print "Input Lat: $lat1  Lon: $lon1\n";
15         print "Input Lat: $lat2 Lon: $lon2\n";
16         print "Output Distance: $dist\n";
17         print "Output Forward Azimuth: $faz\n";
18         print "Output Back Azimuth: $baz\n";
19

DESCRIPTION

21       This module is a pure Perl port of the NGS program in the public domain
22       "inverse" by Robert (Sid) Safford and Stephen J. Frakes.
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CONSTRUCTOR

25       new
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27       The new() constructor may be called with any parameter that is appro‐
28       priate to the ellipsoid method which establishes the ellipsoid.
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30         my $obj = Geo::Inverse->new(); # default "WGS84"
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METHODS

33       ellipsoid
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35       Method to set or retrieve the current ellipsoid object.  The ellipsoid
36       is a Geo::Ellipsoids object.
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38         my $ellipsoid=$obj->ellipsoid;  #Default is WGS84
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40         $obj->ellipsoid('Clarke 1866'); #Built in ellipsoids from Geo::Ellipsoids
41         $obj->ellipsoid({a=>1});        #Custom Sphere 1 unit radius
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43       inverse
44
45       This method is the user frontend to the mathematics. This interface
46       will not change in future versions.
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48         my ($faz, $baz, $dist)=$obj->inverse($lat1,$lon1,$lat2,$lon2);
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TODO

51       Add more tests.
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BUGS

54       Please send to the geo-perl email list.
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LIMITS

57       No guarantees that Perl handles all of the double precision calcula‐
58       tions in the same manner as Fortran.
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AUTHOR

61       Michael R. Davis qw/perl michaelrdavis com/
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LICENSE

64       Copyright (c) 2006 Michael R. Davis (mrdvt92)
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66       This library is free software; you can redistribute it and/or modify it
67       under the same terms as Perl itself.
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SEE ALSO

70       Net::GPSD Geo::Ellipsoid GIS::Distance::GeoEllipsoid
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74perl v5.8.8                       2007-04-06                   Geo::Inverse(3)
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