One way to do it (untested) : 
my $consecutive = 5;
my ($last_range, $first_day);
my %ranges = ( '15'   =>     'mild',
               '20'   =>     'warm',
               '25'   =>     'verywarm',
               '30'   =>     'hot',
               '35'   =>     'veryhot',
               '40'   =>     'extremelyhot');

foreach my $day (@data) {
    $day->[1] = int $day->[1];
    my $range = $day->[1] - ($day->[1] % 5);

    if ($range == $last_range) {
        $seen++;
    } else {
        $last_range = $range;
        $first_day = $day->[0];
        $seen = 1;
    }

    if ($seen == $consecutive) {
        print "$first_day $day->[0] " . 
              $ranges{$range} . "\n";
    }
}

[download]
BTW, a hash table would probably be more appropriate to store your tempature information.

updated : corrected $last_range and $first_day, and make it word in Real world


--
zejames

In reply to Re: Searching in an array of arrays by zejames
in thread Searching in an array of arrays by perl_seeker

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