in reply to XML::LibXML extracting datacolumn

Single column from the root: 

my @lats =
    map $_->getValue(),
    $root->findnodes('//datacolumn[@name="Latitude"]/item/@value');

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All columns: 

my %table;
#for my $col_node ( $root->findnodes('//datacolumn') ) {
for my $col_node ( $table_node->findnodes('datacolumn') ) {
    my $col_name = $col_node->getAttribute('name');
    $table{$col_name} = [
        map $_->getValue(),
        $col_node->findnodes('item/@value')
    ];
}

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I assumed the elements are in the null namespace.

Update: Added second snippet.
Update: s/name=/\@name=/

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Re^2: XML::LibXML extracting datacolumn
by deadpickle (Pilgrim) on Nov 04, 2009 at 00:45 UTC
    not getting anything with this code: 
    #!/usr/bin/perl -w

use strict;
use XML::LibXML;

my $parser = XML::LibXML->new;
my $xmlfile = "20060402-201025.xml";
my $doc = $parser->parse_file($xmlfile);
my $element = $doc->getDocumentElement;

my @nodes = $element->getElementsByTagName('data');

foreach my $kid1(@nodes) {
    my $elname2 = $kid1 -> getName();
    print $elname2,"\n";
    my @lats = map $_->getValue(),$kid1->findnodes('//datacolumn[name=
+"Latitude"]/item/@value');
    print @lats,"\n";
}

    [download]
    The full xml is as follows:
    <?xml version="1.0"?>
<!DOCTYPE datatable>

<datatable>
 <datatype name="ClusterTable">
  <stref>
   <location>
    <lat>
     <angle units="Degrees" value="41.003815"/>
    </lat>
    <lon>
     <angle units="Degrees" value="-93.634293"/>
    </lon>
    <ht>
     <length units="Meters" value="1000.000000"/>
    </ht>
   </location>
   <time units="secondsSinceEpoch" value="1144008625"/>
  </stref>
  <attr name="SubType">
   <datacolumn name="SubType" units="dimensionless">
    <item value="scale_0"/>
   </datacolumn>
  </attr>
  <attr name="scale">
   <datacolumn name="scale" units="dimensionless">
    <item value="0"/>
   </datacolumn>
  </attr>
 </datatype>
 <data>
  <datacolumn name="Latitude" units="Degrees">
   <item value="40.9408"/>
   <item value="40.7698"/>
   <item value="40.5629"/>
   <item value="40.3019"/>
   <item value="39.9689"/>
   <item value="40.0589"/>
   <item value="39.9509"/>
   <item value="39.9149"/>
   <item value="39.4199"/>
   <item value="39.204"/>
   <item value="39.078"/>
   <item value="38.88"/>
   <item value="38.772"/>
   <item value="38.754"/>
   <item value="38.502"/>
   <item value="38.403"/>
   <item value="38.331"/>
   <item value="38.151"/>
   <item value="38.0251"/>
   <item value="37.9981"/>
   <item value="37.8901"/>
   <item value="37.8631"/>
   <item value="37.7461"/>
   <item value="37.4581"/>
   <item value="37.4491"/>
   <item value="37.2601"/>
   <item value="37.2691"/>
   <item value="37.1791"/>
   <item value="37.1971"/>
   <item value="37.0261"/>
   <item value="36.9541"/>
   <item value="36.9271"/>
   <item value="36.5042"/>
   <item value="36.5132"/>
  </datacolumn>
  <datacolumn name="Longitude" units="Degrees">
   <item value="-93.5421"/>
   <item value="-92.9772"/>
   <item value="-92.8504"/>
   <item value="-92.7582"/>
   <item value="-92.6775"/>
   <item value="-92.2971"/>
   <item value="-91.3865"/>
   <item value="-90.9369"/>
   <item value="-92.6314"/>
   <item value="-92.009"/>
   <item value="-92.7698"/>
   <item value="-92.032"/>
   <item value="-92.8966"/>
   <item value="-92.251"/>
   <item value="-92.885"/>
   <item value="-91.9629"/>
   <item value="-92.2395"/>
   <item value="-92.1012"/>
   <item value="-88.3318"/>
   <item value="-92.3663"/>
   <item value="-88.0667"/>
   <item value="-88.228"/>
   <item value="-92.4931"/>
   <item value="-92.6775"/>
   <item value="-92.2395"/>
   <item value="-92.7698"/>
   <item value="-92.4585"/>
   <item value="-92.885"/>
   <item value="-91.8361"/>
   <item value="-92.9081"/>
   <item value="-88.8159"/>
   <item value="-93.104"/>
   <item value="-93.3346"/>
   <item value="-92.8274"/>
  </datacolumn>

    [download]
[reply]
[d/l]
[select]
      First of all, you change $root to $kid1. But I also missed a "@". 
      #!/usr/bin/perl -w

use strict;

use XML::LibXML;

my $xmlfile = "20060402-201025.xml";

my $parser = XML::LibXML->new;
my $doc    = $parser->parse_file($xmlfile);
my $root   = $doc->getDocumentElement;

my @lats =
    map $_->getValue(),
    $root->findnodes(
        '/datatable/data/datacolumn[@name="Latitude"]/item/@value'
    );

print "$_\n" for @lats;

      [download]
[reply]
[d/l]

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