in reply to min and max in a hash of hash

use List::Util qw( min max );

my $max_y = max keys %Year;
my $max_m = max keys %{ $Year{$max_y} };

my $min_y = min keys %Year;
my $min_m = min keys %{ $Year{$min_y} };

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Re^2: min and max in a hash of hash
by wwe (Friar) on Jul 12, 2010 at 16:30 UTC
    Hi ikegami, could you enlighten me what is wrong on using List::Util? the following code works fine, after I corrected the hash provided: 
    foreach my $y (sort keys %Year) {
  my $min_y = List::Util::min values %{ $Year{$y} };
  print "min of [$y] is [$min_y]\n";
}

    [download]
    Edit: this works for sure only if you doesn't care about the month of the min/max value.
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[d/l]

      That will give you the minimum value for each year. The OP wanted just the overall minimum. If he doesn't need the y/m of the minimum, then he could use 

      use List::Util qw( min max );

my $min = min map { min values %{$Year{$_}} } keys %Year;
my $max = max map { max values %{$Year{$_}} } keys %Year;

      [download]

      Update: Fixed s/values/keys/ as per reply.

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[d/l]

        hi, slight correction

        use List::Util qw( min max );

my $min = min map { min values %{$Year{$_}} } keys %Year;
my $max = max map { max values %{$Year{$_}} } keys %Year;

        [download]
[reply]
[d/l]
        I believe he was interested in both the year and month as am I. I currently have the same issue. I have the same data structure using a hash of hash. I would like to report for each year, the month and value of the min and max value. How can your existing example be modified to accommodate this?
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