view m-toolbox/html_help/help/ug/ltpda_training_topic_1_9.html @ 16:91f21a0aab35
database-connection-manager
Update utils.jquery
* * *
Update utils.jmysql.getsinfo
| author |
Daniele Nicolodi <nicolodi@science.unitn.it> |
| date |
Mon, 05 Dec 2011 16:20:06 +0100 (2011-12-05) |
| parents |
f0afece42f48 |
| children |
|
line source
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/1999/REC-html401-19991224/loose.dtd">
<html lang="en">
<head>
<meta name="generator" content=
"HTML Tidy for Mac OS X (vers 1st December 2004), see www.w3.org">
<meta http-equiv="Content-Type" content=
"text/html; charset=us-ascii">
<title>IFO/Temperature Example - Introduction (LTPDA Toolbox)</title>
<link rel="stylesheet" href="docstyle.css" type="text/css">
<meta name="generator" content="DocBook XSL Stylesheets V1.52.2">
<meta name="description" content=
"Presents an overview of the features, system requirements, and starting the toolbox.">
</head>
<body>
<a name="top_of_page" id="top_of_page"></a>
<p style="font-size:1px;"> </p>
<table class="nav" summary="Navigation aid" border="0" width=
"100%" cellpadding="0" cellspacing="0">
<tr>
<td valign="baseline"><b>LTPDA Toolbox</b></td><td><a href="../helptoc.html">contents</a></td>
<td valign="baseline" align="right"><a href=
"ltpda_training_topic_1_7.html"><img src="b_prev.gif" border="0" align=
"bottom" alt="Writing LTPDA scripts"></a> <a href=
"ltpda_training_topic_2.html"><img src="b_next.gif" border="0" align=
"bottom" alt="Topic 2 - Pre-processing of data"></a></td>
</tr>
</table>
<h1 class="title"><a name="f3-12899" id="f3-12899"></a>IFO/Temperature Example - Introduction</h1>
<hr>
<p>
<p>
In your data pack, you will find two raw data series. These are real measurements
of a system that looks like
</p>
<img src="images/ltpda_training_1/ifo_temp_model.png" alt="Model of the IFO/temperature system" width="600px" border="1">
<p>
We have measured the two signals, <tt>T(t)</tt> and <tt>X(t)</tt>. The displacement input to the
interferometer, <tt>dx(t)</tt>, is inaccessible to us, and is in fact the data we want to
recover from the data analysis.
</p>
<br>
<br>
<h2>Reading and calibrating the interferometer data</h2>
<br>
<p>
The interferometer data, X(t), is saved in the file <tt>ifo_temp_example/ifo_training.dat</tt>. This is a
two-column ASCII file with the first column giving the time-stamps of the data and the second column the
measured IFO output in radians.
</p>
<p>
To read in the data, we can use the AO constuctor, with the set of parameters "From ASCII File". The key
parameters are:
<table cellspacing="0" class="body" cellpadding="2" border="0" width="80%">
<colgroup>
<col width="15%"/>
<col width="35%"/>
<col width="50%"/>
</colgroup>
<thead>
<tr valign="top">
<th class="categorylist">Key</th>
<th class="categorylist">Value</th>
<th class="categorylist">Description</th>
</tr>
</thead>
<tbody>
<!-- Key 'filename' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>FILENAME</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p><span class="string">'ifo_temp_example/ifo_training.dat'</span></p>
</td>
<td bgcolor="#f3f4f5">
<p>The name of the file to read the data from.</p>
</td>
</tr>
<!-- Key 'type' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>TYPE</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p><span class="string">'tsdata'</span></p>
</td>
<td bgcolor="#f3f4f5">
<p>Interpret the data in the file as time-series data.</p>
</td>
</tr>
<!-- Key 'columns' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>COLUMNS</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p>[1 2]</p>
</td>
<td bgcolor="#f3f4f5">
<p>Load the data x-y pairs from columns 1 (as x) and 2 (as y).</p>
</td>
</tr>
<!-- Key 'xunits' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>XUNITS</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p><span class="string">'s'</span></p>
</td>
<td bgcolor="#f3f4f5">
<p>Set the units of the x-data to seconds (s).</p>
</td>
</tr>
<!-- Key 'yunits' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>YUNITS</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p><span class="string">'rad'</span></p>
</td>
<td bgcolor="#f3f4f5">
<p>Set the units of the y-data to radians (rad).</p>
</td>
</tr>
<!-- Key 'robust' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>ROBUST</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p><span class="string">'no'</span></p>
</td>
<td bgcolor="#f3f4f5">
<p>Use fast data reading for this simple file format.</p>
</td>
</tr>
<!-- Key 'description' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>DESCRIPTION</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p><span class="string">'Interferometer data'</span></p>
</td>
<td bgcolor="#f3f4f5">
<p>Set some text to the 'description' field of the AO.</p>
</td>
</tr>
</tbody>
</table>
</p>
<p>
Once we've loaded the data we can calibrate it to displacement using the following
equation:
</p>
<img src="images/ltpda_training_1/topic1/ifo_cal_factor.png" alt="Convert rad to m" width="200px" border="1">
<p>
where lambda=1064nm.
</p>
<p>
To do the calibration, you can use the method <tt>ao/scale</tt>,
specifying the <tt>factor</tt> and the <tt>yunits</tt> of the factor
itself. Then save the resulting time-series to disk in <tt>ifo_temp_example/ifo_disp.xml</tt>.
</p>
<p>
A finished pipeline might look something like:
</p>
<img src="images/ltpda_training_1/topic1/ifo_cal_pipeline.png" alt="IFO calibration pipeline" border="1">
<br>
<br>
<h2>Reading and calibrating the temperature data</h2>
<br>
<p>
The temperature data, T(t), is saved in the file <tt>ifo_temp_example/temp_training.dat</tt>. Again, this is a
two-column ASCII file; the first column contains the time-stamps of the data, the second column
contains the temperature values in degrees Celsius.
</p>
<p>
To read in the data, we can use the AO constuctor, with the set of parameters "From ASCII File". The key
parameters are:
<table cellspacing="0" class="body" cellpadding="2" border="0" width="80%">
<colgroup>
<col width="15%"/>
<col width="35%"/>
<col width="50%"/>
</colgroup>
<thead>
<tr valign="top">
<th class="categorylist">Key</th>
<th class="categorylist">Value</th>
<th class="categorylist">Description</th>
</tr>
</thead>
<tbody>
<!-- Key 'filename' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>FILENAME</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p><span class="string">'ifo_temp_example/temp_training.dat'</span></p>
</td>
<td bgcolor="#f3f4f5">
<p>The name of the file to read the data from.</p>
</td>
</tr>
<!-- Key 'type' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>TYPE</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p><span class="string">'tsdata'</span></p>
</td>
<td bgcolor="#f3f4f5">
<p>Interpret the data in the file as time-series data.</p>
</td>
</tr>
<!-- Key 'columns' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>COLUMNS</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p>[1 2]</p>
</td>
<td bgcolor="#f3f4f5">
<p>Load the data x-y pairs from columns 1 (as x) and 2 (as y).</p>
</td>
</tr>
<!-- Key 'xunits' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>XUNITS</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p><span class="string">'s'</span></p>
</td>
<td bgcolor="#f3f4f5">
<p>Set the units of the x-data to seconds (s).</p>
</td>
</tr>
<!-- Key 'yunits' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>YUNITS</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p><span class="string">'degC'</span></p>
</td>
<td bgcolor="#f3f4f5">
<p>Set the units of the y-data to degrees Celsius.</p>
</td>
</tr>
<!-- Key 'robust' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>ROBUST</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p><span class="string">'no'</span></p>
</td>
<td bgcolor="#f3f4f5">
<p>Use fast data reading for this simple file format.</p>
</td>
</tr>
<!-- Key 'description' -->
<tr valign="top">
<td bgcolor="#f3f4f5">
<p><tt>DESCRIPTION</tt></p>
</td>
<td bgcolor="#f3f4f5">
<p><span class="string">'Temperature data'</span></p>
</td>
<td bgcolor="#f3f4f5">
<p>Set some text to the 'description' field of the AO.</p>
</td>
</tr>
</tbody>
</table>
</p>
<p>
Having loaded the temperature data, we can proceed to calibrate it to Kelvin by adding
273.15 to the data and then change the y-units. You can do this using the two AO methods:
<br>
<ul>
<li><tt>offset</tt> -- to add the offset</li>
<li><tt>setYunits</tt> -- to change the y-units of the data</li>
</ul>
</p>
<p>
The final step is to save this calibrated temperature data to disk as an AO XML file called
<tt>ifo_temp_example/temp_kelvin.xml</tt>, ready for input to the next topic.
</p>
<p>
A complete pipeline for this step might look like:
</p>
<img src="images/ltpda_training_1/topic1/temp_cal_pipeline.png" alt="Calibration pipeline for temperature data" border="1">
<p>
<table cellspacing="0" class="note" summary="Note" cellpadding="5" border="1">
<tr width="90%">
<td>
To plot the data with hours on the x-axis instead of seconds, use the <tt>iplot</tt> parameter <tt>XUNITS</tt>.
For example:
<div class="fragment"><pre>
iplot(a, plist(<span class="string">'XUNITS'</span>, <span class="string">'h'</span>))
</pre></div>
</td>
</tr>
</table>
</p>
</p>
<br>
<br>
<table class="nav" summary="Navigation aid" border="0" width=
"100%" cellpadding="0" cellspacing="0">
<tr valign="top">
<td align="left" width="20"><a href="ltpda_training_topic_1_7.html"><img src=
"b_prev.gif" border="0" align="bottom" alt=
"Writing LTPDA scripts"></a> </td>
<td align="left">Writing LTPDA scripts</td>
<td> </td>
<td align="right">Topic 2 - Pre-processing of data</td>
<td align="right" width="20"><a href=
"ltpda_training_topic_2.html"><img src="b_next.gif" border="0" align=
"bottom" alt="Topic 2 - Pre-processing of data"></a></td>
</tr>
</table><br>
<p class="copy">©LTP Team</p>
</body>
</html>
