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Fix. Default password should be [] not an empty string
author Daniele Nicolodi <nicolodi@science.unitn.it>
date Wed, 07 Dec 2011 17:29:47 +0100
parents f0afece42f48
children
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    <tr>
      <td valign="baseline"><b>LTPDA Toolbox</b></td><td><a href="../helptoc.html">contents</a></td>

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  <h1 class="title"><a name="f3-12899" id="f3-12899"></a>Transforming models between representations</h1>
  <hr>
  
  <p>
	<h2>Transforming between different representations</h2>

<p>
  The LTPDA toolbox allows you to go from one representation to the other. However,
  in the current version (v2.3), only the transformations shown in the following
  table are allowed
</p>

<div align="center">
  <img src="images/TransformTable.png" alt="Pole/zero model TF" border="3">
</div>

<p>
  We can see how this work for the allowed transformation using the models that
  we have just created. To turn our <tt>pzmodel</tt> into a <tt>rational</tt>
  one, we just need to insert the first into the rational constructor
</p>
<p>
  For example, if we consider again our <tt>pzmodel</tt>
</p>

<div class="fragment"><pre>
    pzm = pzmodel(5, [10 2],{1, 0.1},<span class="string">'mymodel'</span>)
    ---- pzmodel 1 ----
           name: <span class="string">mymodel</span>
           gain: 5
          delay: 0
         iunits: []
         ounits: []
    description:
           UUID: 9206f503-69c9-4c20-963e-b5604e59b450
    pole 001: (f=10 Hz,Q=2)
    zero 001: (f=1 Hz,Q=NaN)
    zero 002: (f=0.1 Hz,Q=NaN)
    -------------------
</pre></div>

<p>
  To transform it into its rational equivalent we just need to give it as a input to
  the rational constructor
</p>

<div class="fragment"><pre>
    rat = rational(pzm)
    ---- rational 1 ----
    model:       rational(<span class="string">mymodel</span>)
    num:         [1.26651479552922 8.75352187005424 5]
    den:         [0.000253302959105844 0.00795774715459477 1]
    iunits:      []
    ounits:      []
    description:
    UUID:        04b7990b-293c-41a7-a3c9-a311e6f3974b
    --------------------
</pre></div>

<p>
  The transformation returns again the first <tt>pzmodel</tt> however the
  name property allows us to follow the operations that we've been performing to
  this object.
</p>

<div class="fragment"><pre>
    pzm2 = pzmodel(rat)
    ---- pzmodel 1 ----
           name: pzmodel(rational(<span class="string">mymodel</span>))
           gain: 5
          delay: 0
         iunits: []
         ounits: []
    description:
           UUID: b2177fde-1465-4c5c-a94f-29d73d9aed67
    pole 001: (f=10 Hz,Q=2)
    zero 001: (f=1 Hz,Q=NaN)
    zero 002: (f=0.1 Hz,Q=NaN)
    -------------------
</pre></div>











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