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<span class="path"><a href="index.html">FOSSEE Signal Processing Toolbox</a> >> <a href="section_cc2bc01c47967d47fcf3507a91d572ba.html">FOSSEE Signal Processing Toolbox</a> > ifft1</span>
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<div class="refnamediv"><h1 class="refname">ifft1</h1>
<p class="refpurpose">Calculates the inverse discrete Fourier transform of a matrix using Fast Fourier Transform algorithm.</p></div>
<div class="refsynopsisdiv"><h3 class="title">Calling Sequence</h3>
<div class="synopsis"><pre><span class="default">ifft</span><span class="default"> (</span><span class="default">x</span><span class="default">, </span><span class="default">n</span><span class="default">, </span><span class="default">dim</span><span class="default">)</span>
<span class="default">ifft</span><span class="default"> (</span><span class="default">x</span><span class="default">, </span><span class="default">n</span><span class="default">)</span>
<span class="default">ifft</span><span class="default"> (</span><span class="default">x</span><span class="default">)</span></pre></div></div>
<div class="refsection"><h3 class="title">Parameters</h3>
<dl><dt><span class="term">x:</span>
<dd><p class="para">input matrix</p></dd></dt>
<dt><span class="term">n:</span>
<dd><p class="para">Specifies the number of elements of x to be used</p></dd></dt>
<dt><span class="term">dim:</span>
<dd><p class="para">Specifies the dimention of the matrix along which the inverse FFT is performed</p></dd></dt></dl></div>
<div class="refsection"><h3 class="title">Description</h3>
<p class="para">This is an Octave function.</p></div>
<div class="refsection"><h3 class="title">Description</h3>
<p class="para">This is an Octave function.
The inverse FFT is calculated along the first non-singleton dimension of the array. Thus, inverse FFT is computed for each column of x.</p>
<p class="para">n is an integer specifying the number of elements of x to use. If n is larger than dimention along. which the inverse FFT is calculated, then x is resized and padded with zeros.
Similarly, if n is smaller, then x is truncated.</p>
<p class="para">dim is an integer specifying the dimension of the matrix along which the inverse FFT is performed.</p></div>
<div class="refsection"><h3 class="title">Examples</h3>
<div class="programlisting"><table border="0" width="100%"><tr><td width="98%"><pre class="scilabcode"><span class="scilabid">x</span> <span class="scilaboperator">=</span> <span class="scilabopenclose">[</span><span class="scilabnumber">1</span> <span class="scilabnumber">2</span> <span class="scilabnumber">3</span><span class="scilabdefault">;</span> <span class="scilabnumber">4</span> <span class="scilabnumber">5</span> <span class="scilabnumber">6</span><span class="scilabdefault">;</span> <span class="scilabnumber">7</span> <span class="scilabnumber">8</span> <span class="scilabnumber">9</span><span class="scilabopenclose">]</span>
<span class="scilabid">n</span> <span class="scilaboperator">=</span> <span class="scilabnumber">3</span>
<span class="scilabid">dim</span> <span class="scilaboperator">=</span> <span class="scilabnumber">2</span>
<span class="scilabid">ifft1</span> <span class="scilabopenclose">(</span><span class="scilabid">x</span><span class="scilabdefault">,</span> <span class="scilabid">n</span><span class="scilabdefault">,</span> <span class="scilabid">dim</span><span class="scilabopenclose">)</span>
<span class="scilabid">ans</span> <span class="scilaboperator">=</span>
<span class="scilabnumber">2.00000</span> <span class="scilaboperator">+</span> <span class="scilabnumber">0.00000</span><span class="scilabid">i</span> <span class="scilaboperator">-</span><span class="scilabnumber">0.50000</span> <span class="scilaboperator">-</span> <span class="scilabnumber">0.28868</span><span class="scilabid">i</span> <span class="scilaboperator">-</span><span class="scilabnumber">0.50000</span> <span class="scilaboperator">+</span> <span class="scilabnumber">0.28868</span><span class="scilabid">i</span>
<span class="scilabnumber">5.00000</span> <span class="scilaboperator">+</span> <span class="scilabnumber">0.00000</span><span class="scilabid">i</span> <span class="scilaboperator">-</span><span class="scilabnumber">0.50000</span> <span class="scilaboperator">-</span> <span class="scilabnumber">0.28868</span><span class="scilabid">i</span> <span class="scilaboperator">-</span><span class="scilabnumber">0.50000</span> <span class="scilaboperator">+</span> <span class="scilabnumber">0.28868</span><span class="scilabid">i</span>
<span class="scilabnumber">8.00000</span> <span class="scilaboperator">+</span> <span class="scilabnumber">0.00000</span><span class="scilabid">i</span> <span class="scilaboperator">-</span><span class="scilabnumber">0.50000</span> <span class="scilaboperator">-</span> <span class="scilabnumber">0.28868</span><span class="scilabid">i</span> <span class="scilaboperator">-</span><span class="scilabnumber">0.50000</span> <span class="scilaboperator">+</span> <span class="scilabnumber">0.28868</span><span class="scilabid">i</span></pre></td><td valign="top"><a href="scilab://scilab.execexample/"><img src="ScilabExecute.png" border="0"/></a></td><td valign="top"><a href="scilab://scilab.editexample/"><img src="ScilabEdit.png" border="0"/></a></td><td></td></tr></table></div></div>
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