Angle difference between two bearings: Difference between revisions

=={{header|Perl}}==

Perl's built-in modulo is integer-only, so import a suitable one from the <code>POSIX</code> core module

<lang>use POSIX 'fmod';

sub angle {

my($b1,$b2) = @_;

my $b = fmod( ($b2 - $b1 + 720) , 360);

$b -= 360 if $b > 180;

$b += 360 if $b < -180;

return $b;

}

@bearings = (

20, 45,

-45, 45,

-85, 90,

-95, 90,

-45, 125,

-45, 145,

29.4803, -88.6381,

-78.3251, -159.036,

-70099.74233810938, 29840.67437876723,

-165313.6666297357, 33693.9894517456,

1174.8380510598456, -154146.66490124757,

60175.77306795546, 42213.07192354373

);

while(my ($b1,$b2) = splice(@bearings,0,2)) {

printf "%10.2f %10.2f = %8.2f\n", $b1, $b2, angle($b1,$b2);

}

</lang>

{{out}}

<pre> 20.00 45.00 = 25.00

-45.00 45.00 = 90.00

-85.00 90.00 = 175.00

-95.00 90.00 = -175.00

-45.00 125.00 = 170.00

-45.00 145.00 = -170.00

29.48 -88.64 = -118.12

-78.33 -159.04 = -80.71

-70099.74 29840.67 = -139.58

-165313.67 33693.99 = -72.34

1174.84 -154146.66 = -161.50

60175.77 42213.07 = 37.30</pre>