#!/usr/bin/perl -w
###########################################
# mm2rrd
# Mike Schilli, 2007 (m@perlmeister.com)
###########################################
use strict;
use RRDTool::OO;
use Sysadm::Install qw(:all);

my @points;

plough sub {
  chomp;
  my($time, $value) = split / /, $_;
  push @points, [$time, $value];
}, "values.txt";

   # Constructor
my $rrd = RRDTool::OO->new(
	    file => "mmdata.rrd" );

   # Create a round-robin database
$rrd->create(
  step        => 30,
  start       => $points[0]->[0] - 1,
  data_source => { name => "amps",
                   type => "GAUGE" },
  archive     => { rows => 10_000 });

for(@points) {
  $rrd->update(time  => $_->[0], 
               value => $_->[1]);
}

$rrd->graph(
 width  => 600,
 height => 400,
 image          => "mmdata.png",
 vertical_label => "Amperes",
 start          => $points[0]->[0],
 end            => $points[-1]->[0],
 draw           => {
     type   => "line",
     color  => "0000FF",
     legend => "Laptop Power",
 }
);