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Clarify ltpda_uo.retrieve parameters handling
author | Daniele Nicolodi <nicolodi@science.unitn.it> |
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date | Mon, 05 Dec 2011 16:20:06 +0100 |
parents | f0afece42f48 |
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<h2>Description</h2> <p> Resampling is the process of changing the sampling rate of data. <a href="matlab:doc('ao/resample')"><tt>Resample</tt></a> changes the sampling rate of the input AOs to the desired output sampling frequency. LTPDA <a href="matlab:doc('ao/resample')"><tt>resample</tt></a> overloads <tt>resample</tt> function of Matlab Signal Processing Toolbox for AOs. </p> <h2>Syntax</h2> <div class="fragment"><pre> <br> b = resample(a, pl) </pre> </div> <h2>Parameters</h2> <p> The following parameters can be set: <ul> <li> <tt>fsout</tt> - specify the desired output frequency (must be positive and integer)</li> <li> <tt>filter</tt> - specified filter applied to the input, <tt>a</tt>, in the resampling process</li> </ul> </p> <p> <h2>Examples</h2> </p> <p> 2. Resampling a sequence of random data at original sampling rate of 1 Hz at an output sampling of 50 Hz. </p> <div class="fragment"><pre> <br> <span class="comment">% create an AO of random data with fs = 10 Hz</span> pl = plist(<span class="string">'tsfcn'</span>, <span class="string">'randn(size(t))'</span>,<span class="string">'fs'</span>,1,<span class="string">'nsecs'</span>,10,<span class="string">'yunits'</span>,<span class="string">'m'</span>,<span class="string">'nsecs'</span>,100); x = ao(pl); y = resample(x, plist(<span class="string">'fsout'</span>, 50)); <span class="comment">% resample the input AO (x) to obtain the resampled output AO (y)</span> iplot(x, y) <span class="comment">% plot original and resampled data</span> </pre> </div> <br> <br> <img src="images/resample1.png" alt="Resample"> <br> <br> <br> <p> 1. Resampling a sequence of random data at original sampling rate of 10 Hz at an output sampling of 1 Hz with a filter defined by the user. </p> <div class="fragment"><pre> <br> <span class="comment">% create an AO of random data with fs = 10 Hz</span> pl = plist(<span class="string">'tsfcn'</span>, <span class="string">'randn(size(t))'</span>,<span class="string">'fs'</span>,10,<span class="string">'nsecs'</span>,10,<span class="string">'yunits'</span>,<span class="string">'m'</span>); x = ao(pl) <span class="comment">% filter definition</span> plfilter = plist(<span class="string">'type'</span>,<span class="string">'lowpass'</span>,<span class="string">'Win'</span>,specwin(<span class="string">'Kaiser'</span>, 10, 150),<span class="string">'order'</span>,32,<span class="string">'fs'</span>,10,<span class="string">'fc'</span>,1); f = mfir(plfilter) <span class="comment">% resampling</span> pl = plist(<span class="string">'fsout'</span>, 1, <span class="string">'filter'</span>,f); <span class="comment">% define parameters list with fsout = 1 Hz and the defined filter</span> y = resample(x, pl); <span class="comment">% resample the input AO (x) to obtain the resampled output AO (y)</span> iplot(x, y) <span class="comment">% plot original and resampled data</span> </pre> </div> <br> <br> <img src="images/resample2.png" alt="Resample" border="0">