Dear perlMonks,
I have the following problem:
A have an XML output(1GB) of a database of chemical compounds and I would like to extract just some parametrs for every and single of them. I tried to get oriented in examples for XML:twig and the only result of my tries is the code below (XML is completly new for me and perl almost completly). The trouble is that extracting the records of interest(PC-CompoundType_id_cid,PC-InfoData_value_binary) the way I do can lead to troubles when the item for some compound is missing
. Thanks for your help. karpatov 
#!/bin/perl -w
use strict;
use XML::Twig;

my $leader_name;
my $leader_score=0;

#my $field0= 'PC-Compound';
my $field1= 'PC-CompoundType_id_cid';
my $field2= 'PC-InfoData_value_binary';

my $twig= new XML::Twig( twig_roots    => {$field1 => 1, $field2 => 1 
+} );
$twig->parsefile( "D:/NCI-Open/vice shlavickou.xml");
my $root= $twig->root;
my @cpds= $root->children_text($field1);
my @bins= $root->children_text($field2);
print "@cpds\n";
print "@bins\n";
#$twig->print;

[download]

Simplified XML:
<PC-Compound>
    <PC-Compound_id>
      <PC-CompoundType>
        <PC-CompoundType_id>
          <PC-CompoundType_id_cid>1</PC-CompoundType_id_cid>
        </PC-CompoundType_id>
      </PC-CompoundType>
    </PC-Compound_id>
    <PC-Compound_atoms>
    </PC-Compound_atoms>
    
    
   
    <PC-Compound_props>
      <PC-InfoData>
      </PC-InfoData>

      <PC-InfoData>
        <PC-InfoData_urn>
          <PC-Urn>
          </PC-Urn>
        </PC-InfoData_urn>
        <PC-InfoData_value>
          <PC-InfoData_value_binary>00000371E0723800000000000000000000
+000000000000000000000000000000000000000000001E00000000000814E18006020
+803000400080000900800000000000000000001080000020014008000070000052000
+1000002400000000000000000000000000000000000000000000000000</PC-InfoDa
+ta_value_binary>
        </PC-InfoData_value>
      </PC-InfoData>
      
      <PC-InfoData>
      </PC-InfoData>
      
  </PC-Compound>

[download]

In reply to 1GB XML mining with XML:twig (newbies question) by karpatov

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