I have some code:
use DateTime;
use DateTime::Event::Sunrise;
use strict;

my $timezone = "Pacific/Auckland";
my ( $latitude, $longitude ) = ( -36.55, 174.45 );

my $dt_start = DateTime->new(
    year       => 2006,
    month      => 3,
    day        => 1,
    hour       => 4,
    time_zone  => $timezone,
);

my $dt_end = $dt_start->clone()->add(days=>31);

for ( my $dt = $dt_start->clone();
      $dt < $dt_end;
      $dt->add(days=>1)
     )
{
    my $sset = DateTime::Event::Sunrise->sunset(
        longitude => $longitude,
        latitude => $latitude,
        altitude => '-0.833',
        iteration => '1'
    );

    my $dt_ss = $sset->next($dt);

    print( "Sunset on "
           . $dt->strftime("%d %B %Y")
           . " at "
           . $dt_ss->strftime("%H:%M")
           . "\n"
          );
}

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This code prints out the sunset time for each day of March 2006 in Auckland, New Zealand.

When running this code it complains that the sun never sets on 22 March 2006, which is clearly not the case in Auckland.

Running the above code with the sunset object set to iteration => '0' works fine (although less accurately).

Any ideas why I'm getting this:

Sunset on 19 March 2006 at 18:38
Sunset on 20 March 2006 at 18:36
Sunset on 21 March 2006 at 18:33
Sun never sets!!
 at /usr/lib/perl5/vendor_perl/5.8.5/DateTime/Set.pm line 240
Sun never sets!!
 at /usr/lib/perl5/vendor_perl/5.8.5/DateTime/Set.pm line 240
Sun never rises!!
 at /usr/lib/perl5/vendor_perl/5.8.5/DateTime/Set.pm line 240
Sun never rises!!

[download]

In reply to Sun Never Sets by monarch

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