Give this a shot. 
use Math::Trig qw(great_circle_distance deg2rad rad2deg);

sub NESW { 
    Math::Trig::deg2rad($_[0]), Math::Trig::deg2rad(90 - $_[1])
}

sub distance {
    my ($lat1, $lon1, $lat2, $lon2) = @_;
    my @src = NESW($lon1, $lat1);
    my @dest = NESW($lon2, $lat2);
    great_circle_distance(@src, @dest, 6378);
}

sub bearing {
  my ($lat1, $lon1, $lat2, $lon2) = @_;
  my @src  = NESW($lon1, $lat1);
  my @dest = NESW($lon2, $lat2);
  rad2deg(Math::Trig::great_circle_direction(@src, @dest));
}

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In reply to Re: Finding distance between cities or countries Perl module by not_japh
in thread Finding distance between cities or countries Perl module by maheshkumar

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