#!/usr/bin/perl -w
 use strict;
 use RRDTool::OO;

 my @points = ();

 while( <> ) {
   chomp;
   my($time, $value) = split /,/, $_;
   push @points, [$time, split /:/, $value];
 }

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

 $rrd->create(
   step        => 3600*24*45,
   start       => $points[0]->[0] - 1,
   data_source => { name => "high",
                    type => "GAUGE" },
   data_source => { name => "low",
                    type => "GAUGE" },
   archive     => { rows => 10_000 });

 for(@points) {
   $rrd->update(
     time   => $_->[0],
     values => [ @{ $_ }[1,2] ] );
 }

 $rrd->graph(
  width  => 600,
  height => 400,
  image          => "blood-pressure.png",
  vertical_label => "Blood Pressure",
  start          => $points[0]->[0],
  end            => $points[-1]->[0],
  draw           => {
      legend => "systolic",
      dsname => "high",
      type   => "area",
      color  => "FF0000",
  },
  draw           => {
      legend => "diastolic",
      dsname => "low",
      type   => "area",
      color  => "00FF00",
  }
 );