Some people prefer an explicit subscript to a short list assignment:

my  $max  = (expr)[0];   # rather than
my ($max) = list_expr;
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Update: Or, sure, you scan linearly like CountZero suggests. That's the Right Way to do this kind of thing in general (unless you go for the tied hash). But if you know your data to be this size, it probably doesn't matter much.

use strict;
use warnings;

my %some_hash = (
           sunny => .63,
           cloudy => .17,
           rainy => .2
           );

my @key_list = keys %some_hash;
my $max_key = pop @key_list;

foreach (@key_list) {
    $max_key = $_ if $some_hash{$_} > $some_hash{$max_key};
}

print $max_key." :: ".$some_hash{$max_key}."\n";
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For some reason, each strikes me as a slightly more natural way to do this. If nothing else, it avoids the construction of the key list.

my %h =
(
    sunny   => 0.063,
    cloudy  => 0.017,
    rainy   => 0.020,
    hellish => 0.103,
);

my( $max_key, $max_val ) = each %h;

while ( my($k,$v) = each %h )
{
    $v > $max_val and ($max_key,$max_val) = ($k,$v);
}

print "$max_key => $max_val\n";
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We're building the house of the future together.

#! perl -slw
use strict;
use List::Util qw[ max ];

my %some_hash = ( sunny => .63, cloudy => .17, rainy => .2 );
my $max = max values %some_hash;
print +{ reverse %some_hash }->{ $max }, ' :: ', $max;

__END__
C:\test>539366
sunny :: 0.63
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thanks for the replies! all very helpful. I think that this last was what I was most curious about though - how to print the key, given the value. but what happens where there are two keys that share the same value? and what is the 'l' option in the shebang ??

but what happens where there are two keys that share the same value?

You'll get the weather associated with one of the maximal values--which one is determined by the hashing algorithm and the text of the keys.

This is exactly the same effect as with your sort sort method.

and what is the 'l' option in the shebang ??

It sets $/ & $\ (INPUT and OUTPUT SEPARATORS) to \n. It just saves having to type  . "\n"; each time. One downside is that if you use a module that uses "\n" explicitly when printing stuff, it ends up double spaced, but it's useful for standalone scripts.

---

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