in reply to Re^4: perl parsing
in thread perl parsing

Change this line to build a Hash of Arrays (HoA)

#push @{$hash{$name}},$col2,$col3;
push @{$hash{$name}},"$col2\t$col3"; # device year

[download]

and change the output loop to

foreach my $name (keys %hash){
  print "$name\n";
  foreach my $sit (@{$hash{$name}}){
    print "\t$sit\n";
  }
}

[download]
poj

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Re^6: perl parsing
by cbtshare (Monk) on Oct 06, 2017 at 19:11 UTC

    Thank you poj!!! .Can you help me understand please, how would I know not to use foreach my $sit (keys %{$hash{$line}}) when tutorials are saying I was to do it that way, but to use foreach my $sit (@{$hash{$name}}).

    Why did I need to \t when creating the hoh and not use ,<comma> when Dumper had the correct info just couldnt print it out

    #push @{$hash{$name}},$col2,$col3;
push @{$hash{$name}},"$col2\t$col3"; # device year

    [download]

    2017-10-08 Athanasius added code tags

[reply]
[d/l]
[select]
      Dumper had the correct info

      If your output was like this 

      $VAR1 = {
          'ryan' => [
                      'ipad',
                      '2005',
                      'cell',
                      '2009'
                    ],
          'Brian' => [
                       'ipad',
                       '2001',
                       'ipad',
                       '2001',
                       'ipad',
                       '2001'
                     ],
          'Andrew' => [
                        'ipad',
                        '2009'
                      ]
        };

      [download]

      that is not a HashOfHashes, it is a HashOfArrays. push @{$hash{$name}},$col2,$col3 is creating 2 array element for each line of data

      push @{$hash{$name}},"$col2,$col3" creates only 1 array element for each line. see push

      A HashOfHashes (HoH) would be used if you wanted to replace multiple records the same with 1 record and a count, like this

      while (<IN>){
  s/^\s+|\s+$//g; # trim leading/trailing spaces
  my ($col1,$col2,$col3) = split /\s+/,$_,4;
  if ($col1 eq 'name'){
    $name = $col2;   
  } elsif ($col1 eq 'device') {
    #push @{$hash{$name}},"$col2\t$col3";
    ++$hash{$name}{$col2}{$col3}; #HoH
  } else {
    # skip line
  }
}
close IN;

foreach my $name (keys %hash){
  print "$name\n";
  foreach my $col2 (keys %{$hash{$name}}){
    foreach my $col3 (keys %{$hash{$name}{$col2}}){
      my $count = $hash{$name}{$col2}{$col3};
      print "\t$col2\t$col3\t$count\n";
    }
  }
}

      [download]
      poj
[reply]
[d/l]
[select]

        I am guessing you made a typo, you meant push @{$hash{$name}},$col2,$col3 is creating 2 array element for each line of data and push @{$hash{$name}},"$col2\t$col3" creates only 1 array element for each line

        right?
[reply]

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