Tried many a thing to get this short code to run but all I get it 0 distance for an answer odd because it totally seem like it should work. 
#!/usr/local/bin/perl5
use Math::Trig qw(deg2rad pi great_circle_distance asin acos);

############################
## Distances are in Miles ##
############################
 

$lat1 = 51.29006786;
$long1 = -114.0034133;
$lat2 = 54.431963;
$long2 = -110.20734554;         

{
    ($lat1, $long1, $lat2, $long2) = @_;
    $r=3956;

    $a = (pi/2)- deg2rad($lat1);               
    $b = (pi/2)- deg2rad($lat2);
    $c = sqrt($a**2 + $b**2 - 2 * $a *$b
            *cos(deg2rad($long2)-deg2rad($long1)));
    $dist = $c * $r;

}
print "$dist\n";

[download]
Thanks for any help in advance.

In reply to flat earth distance by pglinx

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