Hash of Hashes not filling - only using last line of file

kdmurphy001 has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks, My Hash of Hases isn't filling up. When I look at hte size of it it's only 1 (1 key) and if I print out the entire hash only the last line of the file being read in is present. The file/data is solid - and sadly I can't share what's in the file but I've used it else where /w similiar scripts w/o issue. Here's the code that's building the hash of hashes.

while (my $line=<FILE>) {
    chomp($line);
    my ($IacIsbn, $Title, $EPI, $BundleCode) = split("\t",$line);
    %IACISBN_ENUM = (
        $IacIsbn => {
            'Title' => $Title,
            'EPI' => $EPI,
            'Bundle' => $BundleCode
        }
    );
}
close FILE;
[download]

Any ideas? If I put in a print statement all the lines are being read into the values correctly and I can print them using the hash IE $IACISBN_ENUM{$isbn}{Title} prints out the title - if I'm in the above while loop ($isbn would be a key). Out side the while loop above though only the last element is showing up - IE it's like Im overwritting the values each time instead of adding.

Comment on Hash of Hashes not filling - only using last line of file Download Code

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Re: Hash of Hashes not filling - only using last line of file by fullermd (Priest) on Feb 22, 2013 at 07:54 UTC
Because that's exactly what you're asking it to do; every time through the `while()`, you're setting `%IACISBN_ENUM` to a hash with a single key. You want to add keys to it each time, not re-initialize it. Try something more like: `$IACISBN_ENUM{$IacIsbn} = { [...] };` [download]	[reply] [d/l] [select]
Re: Hash of Hashes not filling - only using last line of file by 7stud (Deacon) on Feb 22, 2013 at 08:04 UTC
`use strict; use warnings; use 5.012; my %hash; %hash = ('a' => 10); %hash = ('b' => 20); use Data::Dumper; say Dumper(\%hash); --output:-- $VAR1 = { 'b' => 20 };` [download] Compare to: `use strict; use warnings; use 5.012; my %hash; $hash{a} = 10; $hash{b} = 20; use Data::Dumper; say Dumper(\%hash); --output:-- $VAR1 = { 'a' => 10, 'b' => 20 };` [download] The real values I used instead of 'a' and 'b' are proprietary information, but hopefully you get the idea.	[reply] [d/l] [select]
Re: Hash of Hashes not filling - only using last line of file by poolpi (Hermit) on Feb 22, 2013 at 08:10 UTC
You have to put your hash out of the while loop. `#!/usr/bin/perl -w use strict; use Data::Dumper; my %IACISBN_ENUM; while ( my $line = <DATA> ) { chomp($line); my ( $IacIsbn, $Title, $EPI, $BundleCode ) = split( "\t", $line ); $IACISBN_ENUM{$IacIsbn} = { 'Title' => $Title, 'EPI' => $EPI, 'Bundle' => $BundleCode }; } print Dumper \%IACISBN_ENUM; __END__ IacIsbn Title EPI BundleCode` [download] hth, PooLpi The stone that the builder refused, will always be the head cornerstone. [ Robert Nesta MARLEY ]	[reply] [d/l]
Re: Hash of Hashes not filling - only using last line of file by Bloodnok (Vicar) on Feb 22, 2013 at 11:31 UTC
As has been posted elsewhere, you're resetting the hash for each line you read - in addition to the other suggestions, TIMTOWTDI, so you could try something along the lines of ... `my %IACISBN_ENUM = map { chomp($line); my ($IacIsbn, $Title, $EPI, $BundleCode) = split "\t"; ( $IacIsbn => { 'Title' => $Title, 'EPI' => $EPI, 'Bundle' => $BundleCode } ) } <FILE>; close FILE;` [download] A user level that continues to overstate my experience :-))	[reply] [d/l]


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