Lab::Measurement - Log, describe and plot data on the fly

  use Lab::Measurement;

  my $measurement=new Lab::Measurement(
      sample            => $sample,
      title             => $title,
      filename_base     => 'qpc_pinch_off',
      description       => $comment,

      live_plot         => 'QPC current',

      columns           => [
          {
              'unit'            => 'V',
              'label'           => 'Gate voltage',
              'description'     => 'Applied to gates via low path filter.',
          },
          {
              'unit'            => 'V',
              'label'           => 'Amplifier output',
              'description'     => "Voltage output by current amplifier set to $amp.",
          }
      ],
      axes              => [
          {
              'unit'            => 'V',
              'expression'      => '$C0',
              'label'           => 'Gate voltage',
              'min'             => ($start_voltage < $end_voltage) ? $start_voltage : $end_voltage,
              'max'             => ($start_voltage < $end_voltage) ? $end_voltage : $start_voltage,
              'description'     => 'Applied to gates via low path filter.',
          },
          {
              'unit'            => 'A',
              'expression'      => "abs(\$C1)*$amp",
              'label'           => 'QPC current',
              'description'     => 'Current through QPC',
          },
          {
              'unit'            => '2e^2/h',
              'expression'      => "(\$A1/$v_sd)/$g0)",
              'label'           => "Total conductance",
          },
          {
              'unit'            => '2e^2/h',
              'expression'      => "(1/(1/abs(\$C1)-1/$U_Kontakt)) * ($amp/($v_sd*$g0))",
              'label'           => "QPC conductance",
              'min'             => -0.1,
              'max'             => 5
          },

      ],
      plots             => {
          'QPC current'    => {
              'type'          => 'line',
              'xaxis'         => 0,
              'yaxis'         => 1,
              'grid'          => 'xtics ytics',
          },
          'QPC conductance'=> {
              'type'          => 'line',
              'xaxis'         => 0,
              'yaxis'         => 3,
              'grid'          => 'ytics',
          }
      },
  );

  $measurement->start_block();

  my $stepsign=$step/abs($step);
  for (my $volt=$start_voltage;$stepsign*$volt<=$stepsign*$end_voltage;$volt+=$step) {
      $knick->set_voltage($volt);
      usleep(500000);
      my $meas=$hp->read_voltage_dc(10,0.0001);
      $measurement->log_line($volt,$meas);
  }

  my $meta=$measurement->finish_measurement();

This module simplifies the task of running a measurement, writing the data to disk and keeping track of necessary meta information that usually later you don't find in your lab book anymore.

If your measurements don't come out nice, it's not because you were using the wrong software.

  $measurement=new Lab::Measurement(%config);

where %config can contain

  sample        => '',  # see Meta
  title         => '',  # single line
  filename      => '',
  filename_base => '',  # for auto_naming
  description   => '',  # multi line

  columns       => [],
  axes          => [],
  plots         => [],  # See Meta

  live_plot     => '',  # Name of plot that is to be plotted live
  live_refresh  => '',
  live_latest   => '',

  writer_config => {},  # Configuration options for Lab::Data::Writer

  $block_num=$measurement->start_block($label);

  $measurement->log_line(@data);

  $meta=$measurement->finish_measurement();

  $now=$measurement->now_string();

magic log. deprecated.

Lab::Data::Meta

Lab::Data::Writer

Lab::Data::Plotter

This is $Id: Measurement.pm 495 2006-08-14 15:46:01Z schroeer $

Copyright 2004-2006 Daniel Schröer (http://www.danielschroeer.de)

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.