Re^2: Sort Hash of hashes

I don't need to display the hash at all. Later on in the program I am storing just the key within an array,

@tags = keys %{ $bigrams{$element}}
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Is there a way to sort the key by there value.

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Re^3: Sort Hash of hashes by Marshall (Canon) on Mar 22, 2016 at 23:40 UTC
Yes! here is a short program to illustrate the idea: `#/usr/bin/perl use warnings; use strict; my %hash = (a => 4, b => 6, c => 2); my @sorted_keys = sort keys %hash; print "@sorted_keys\n"; my @sort_by_value = sort{my $A = $hash{$a}; my $B = $hash{$b}; $A <=> $B ## or cmp for strings }keys %hash; print "@sort_by_value\n"; __END__ Prints: a b c # simple key sort c a b # keys sorted by value of keys` [download] The sort{} takes input from the right and sends the same output to the left except in a different order. What goes inside the {} are the "rules" for how to sort the input. $a and $b are special Perl variables that are assigned various values as needed to sort the input. The "return value" of the sort {} should be <0,0,>0 just like the cmp statement does for strings or the "spaceship" operator, <=> does for numbers.	[reply] [d/l]

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Re^3: Sort Hash of hashes
by Marshall (Canon) on Mar 22, 2016 at 23:40 UTC

#/usr/bin/perl
use warnings;
use strict;

my %hash = (a => 4,
            b => 6,
            c => 2);
            
my @sorted_keys = sort keys %hash;
print "@sorted_keys\n";

my @sort_by_value = sort{my $A = $hash{$a};
                         my $B = $hash{$b};
                            $A <=> $B  ## or cmp for strings
                        }keys %hash;
                        
print "@sort_by_value\n";

__END__
Prints:
a b c  # simple key sort
c a b  # keys sorted by value of keys
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