The Test::Parser::Iostat has a data method which provides a hash, no need to parse the XML. This example plots a histogram of util against elapsed time for sda2 from a file created with iostat sda2 -x 1 10 > iostat.txt.

#!/usr/bin/perl
use strict;
use Test::Parser::Iostat;
use GD::Graph::bars;

my $parser = new Test::Parser::Iostat();
open IN,'iostat.txt' or die "$!";
$parser->parse(\*IN) or die $parser->error(), "\n";
my $hash =  $parser->data();

# create plot data
my @plot=([],[]);
for my $ar (@{$hash->{'iostat'}{'data'}}){
  if ($ar->{'device'} eq 'sda2'){
    push @plot[0],$ar->{'elapsed_time'};
    push @plot[1],$ar->{'util'};
  }
}

# create graph
my $graph = GD::Graph::bars->new(400, 300);
$graph->set( 
      x_label           => 'Elapsed time',
      y_label           => 'Util',
      title             => 'sda2 util',
      y_max_value       => 100,
  ) or die $graph->error;
  
 my $gd = $graph->plot(\@plot) or die $graph->error;  
 open(IMG, '>iostat.gif') or die $!;
 binmode IMG;
 print IMG $gd->gif;

[download]
poj

In reply to Re^3: I need to create a graph from a hash using GD else GD::Graph by poj
in thread I need to create a graph from a hash using GD else GD::Graph by rahulruns

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