Different hashes?

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

Monks
I have an inventory (textfile) with the following:
Category ID Name Type Size
=======================================
WaterSports 8765 Drysuit r M-L
WaterSports 8365 Paddle t 45
…
WinterSports 5231 Snowboard j 85
WinterSports 5281 Gloves r S
Etc..
I want to create a hash of hashes like the following

$VAR1 = {
          'WaterSports' => [
                          '8765',
                          [
                            'Drysuit',
                            'r',
                            'M-L'
                          ]
                          '8365',
                          [
                            'Paddle',
                            't',
                            '45'
                          ]
                        ]
        };
[download]

But instead my code is creating this, what is wrong?

$VAR1 = {
      'WaterSports' => [
                          '8765',
                          [
                            'Drysuit',
                            'r',
                            'M-L'
                          ]

        };
$VAR1 = {
          'WaterSports'=> [
                          '8365',
                          [
                            'Paddle',
                            't',
                            '45'
                          ]
                    ]
        };
[download]

This is my code:

open(INFILE, "products-id.txt")|| die "Cannot open products-id.txt fil
+e"; 
open (OUTPUT,">$output") or die ("Can't open file $output $!");

chomp(my @ProductArray = map { /^\s*$/ ? () : $_ } <INFILE>);
close (INFILE);

foreach my $line(@ProductArray)
{
  my ($Category, $ID, $Name, $Type, $Size) = split( / /, $line );

  %AllProducts = ($Category => [$ID, [$Name, $Type, $Size]]);

print OUTPUT Dumper(\%AllProducts);

}
[download]

Thanks is advance!!

Comment on Different hashes? Select or Download Code

Replies are listed 'Best First'.
Re: Different hashes? by Fletch (Bishop) on Mar 26, 2004 at 14:58 UTC
You're clearing out the entire hash each time through the loop and replacing it with new contents. You want `push @{ $AllProducts{ $Category } }, [ $ID, [ $Name, $Type, $Size ] ]`. See `perldoc perlreftut`, `perldoc perldsc`, and `perldoc perllol`.	[reply] [d/l] [select]
Re: Re: Different hashes? by Happy-the-monk (Canon) on Mar 26, 2004 at 15:12 UTC
Fletch and borisz: the outer array referencing brackets `[ ]` are still wrong, take them away and you got it right.	[reply]
Re: Re: Re: Different hashes? by Fletch (Bishop) on Mar 26, 2004 at 16:19 UTC
Actually what he probably really wants is a HOH and should be doing something like: `$AllProducts{ $Category }->{ $ID } = { name => $Name, type => $Type, s +ize => $Size };` [download] But that's why he should read `perldoc perldsc`.	[reply] [d/l] [select]
Re: Different hashes? by tcf22 (Priest) on Mar 26, 2004 at 15:04 UTC
You are overwriteing the key in %AllProducts every loop. You need to make the hash value an array ref then push onto it. Try this: `foreach my $line(@ProductArray) { my ($Category, $ID, $Name, $Type, $Size) = split( / /, $line ); unless(exists $AllProducts{$Category}){ $AllProducts{$Category} = []; } push(@{$AllProducts{$Category}}, $ID, [$Name, $Type, $Size]); print OUTPUT Dumper(\%AllProducts); }` [download] - Tom	[reply] [d/l]
Re: Different hashes? by borisz (Canon) on Mar 26, 2004 at 15:07 UTC
`#!/usr/bin/perl use Data::Dumper; my %products; while (defined( $_ = <DATA> )){ next if $. <= 2 \|\| /^\s*$/; my @d = split ' '; my $cat = shift @d; my $id = shift @d; push @{$products{$cat}}, [ $id, \@d ]; } print Dumper(\%products); __DATA__ Category ID Name Type Size ======================================= WaterSports 8765 Drysuit r M-L WaterSports 8365 Paddle t 45 WinterSports 5231 Snowboard j 85 WinterSports 5281 Gloves r S` [download] Boris	[reply] [d/l]
Re: Different hashes? by Happy-the-monk (Canon) on Mar 26, 2004 at 15:03 UTC
Make the following change to your code: - ~~`%AllProducts = ($Category => [$ID, [$Name, $Type, $Size]]);`~~ + `push @{ AllProducts{$Category} }, ( $ID, [$Name, $Type, $Size] );` what was wrong? redefined the hash while looping, thus overwriting it. made a new array reference instead of pushing onto it. Cheers, Sören	[reply] [d/l] [select]
Re: Different hashes? by Anonymous Monk on Mar 26, 2004 at 15:36 UTC
Thank you Monks and thanks for you comments!! It is working now :)	[reply]
Different hashes part II by Anonymous Monk on Mar 26, 2004 at 16:29 UTC
Hello Monks I just send a message not long ago (different hashes?), and I tried your suggestions. I thought it was working because I run the script with a small textfile, but it is not!! :( It is creating a new hash, adding a new record at the time. it's exponential huge `$VAR1 = { 'WaterSports' => [ '8765', [ 'Drysuit', 'r', 'M-L' ] }; $VAR1 = { 'WaterSports'=> [ '8765', [ 'Drysuit', 'r', 'M-L' ] '8365', [ 'Paddle', 't', '45' ] ] };` [download] This is my modify code: `open(INFILE, "products-id.txt")\|\| die "Cannot open products-id.txt fil +e"; open (OUTPUT,">$output") or die ("Can't open file $output $!"); chomp(my @ProductArray = map { /^\s*$/ ? () : $_ } <INFILE>); close (INFILE); foreach my $line(@ProductArray) { my ($Category, $ID, $Name, $Type, $Size) = split( / /, $line ); push(@{$AllProducts{$Category}}, $ID, [$Name, $Type, $Size]); print OUTPUT Dumper(\%AllProducts); }` [download] I also tried this `push @{$AllProducts{$Category}}, ($ID, [$Name, $Type, $Size]);` [download] Thanks	[reply] [d/l] [select]
Re: Different hashes part II by Anonymous Monk on Mar 26, 2004 at 16:50 UTC
I am trying borisz's solutions, but as well as the others it's taking too much time to execute, so I cancelled it.. but this time the PARTIAL output I am getting is OK, I am not sure it is repeating the whole thing over and over.. `Borisz's script: #!/usr/bin/perl use Data::Dumper; my %products; while (defined( $_ = <DATA> )){ next if $. <= 2 \|\| /^\s*$/; my @d = split ' '; my $cat = shift @d; my $id = shift @d; push @{$products{$cat}}, [ $id, \@d ]; } print Dumper(\%products);` [download]	[reply] [d/l]
Re: Re: Different hashes part II by Anonymous Monk on Mar 26, 2004 at 17:15 UTC
It is OK, I should not print the dumper(\%product) to the output file, inside the loop mmmmmm sorry about that	[reply]
Re: Different hashes part II by graff (Chancellor) on Mar 26, 2004 at 17:21 UTC
It might have been better to make this a reply or update to your earlier post. Since you seemed to have missed the point of advice that others gave there, I think I'll post a reply there myself, because more information is available there regarding the problem. (In fact, maybe the present thread should be "considered" for removal or relocation.)	[reply]