Grep hash of hashes

pimperator has asked for the wisdom of the Perl Monks concerning the following question:

in anno MMXIV o monachis

I have this input file I want to turn into a multidimensional hash

NAME    NUMBER    COLOR
GNAEUS    1    BLUE
GNAEUS    1    RED
FABIUS      1    BLUE
FABIUS      2    YELLOW
 FABIUS    1    RED
....
[download]

This is how I am turning it into a hash of hashes

undef my %hash;
open IN, $ARGV[0];
while(<IN>){
    chomp $_;
    my ($name,$number,$color) = split /\t/, $_;
    $hash{$name}{$number}{$color}++;
}
[download]

Here's some pseudo-code of what I'm trying to accomplish

 
my %returnedHash = grep / $hash{"GNAEUS"}{"1"} / keys %hash; 

foreach my $name (keys %returnedHash){ 
        
    foreach my $number (keys %{$returnedHash{$name}}){
            
        foreach my $color (keys %{$returnedHash{$name}{$number}}){
                     
            print $returnedHash{$name}{$number}{$color};
        }
    }
}
[download]

I'm at a loss at the moment. That's why I'm here. Please help me o'Monks

Comment on Grep hash of hashes Select or Download Code

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Re: Grep hash of hashes by choroba (Cardinal) on Dec 02, 2014 at 09:27 UTC
Do you only want to see the counts? I guess not, you also want to see the number and colour to which the count belongs. BTW, the main point of $_ is you don't have to write it. If there's no assingment in a my statement, there's no need to undef it. Read more... (753 Bytes) لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ	[reply] [d/l]
Re: Grep hash of hashes by Anonymous Monk on Dec 02, 2014 at 08:06 UTC
Read more... (419 Bytes) Anyway, my advice, see Data::Dive example, Data::Dump::dd() early and often, write real code, start with dd( \%hash ) output, and build your loops on top of that, when you get stuck, post your code	[reply]
Re: Grep hash of hashes by McA (Priest) on Dec 02, 2014 at 08:08 UTC
Hi, why do you need a deeply nested structure `returnedHash` when you know that the first two levels of keys are constant? Why don't you simply collect the last level? McA	[reply] [d/l]
Re^2: Grep hash of hashes by Anonymous Monk on Dec 02, 2014 at 09:35 UTC
You seemed to have missed the fabulous FABIUS in yellow, rendering the second level not being constant.	[reply]
Re^3: Grep hash of hashes by McA (Priest) on Dec 02, 2014 at 09:49 UTC
It seems I've misunderstood the whole problem. But that's the problem when you don't describe the problem clearly. So, you see, nothing but problems... ;-)	[reply]