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<div class="section" id="multilevel-dwt-idwt-and-swt">
<span id="reg-multilevel"></span><h1>Multilevel DWT, IDWT and SWT<a class="headerlink" href="#multilevel-dwt-idwt-and-swt" title="Permalink to this headline">¶</a></h1>
<div class="section" id="multilevel-dwt-decomposition">
<h2>Multilevel DWT decomposition<a class="headerlink" href="#multilevel-dwt-decomposition" title="Permalink to this headline">¶</a></h2>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="kn">import</span> <span class="nn">pywt</span>
<span class="gp">>>> </span><span class="n">x</span> <span class="o">=</span> <span class="p">[</span><span class="mi">3</span><span class="p">,</span> <span class="mi">7</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="o">-</span><span class="mi">2</span><span class="p">,</span> <span class="mi">5</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="mi">6</span><span class="p">]</span>
<span class="gp">>>> </span><span class="n">db1</span> <span class="o">=</span> <span class="n">pywt</span><span class="o">.</span><span class="n">Wavelet</span><span class="p">(</span><span class="s">'db1'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">cA3</span><span class="p">,</span> <span class="n">cD3</span><span class="p">,</span> <span class="n">cD2</span><span class="p">,</span> <span class="n">cD1</span> <span class="o">=</span> <span class="n">pywt</span><span class="o">.</span><span class="n">wavedec</span><span class="p">(</span><span class="n">x</span><span class="p">,</span> <span class="n">db1</span><span class="p">)</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">cA3</span>
<span class="go">[ 8.83883476]</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">cD3</span>
<span class="go">[-0.35355339]</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">cD2</span>
<span class="go">[ 4. -3.5]</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">cD1</span>
<span class="go">[-2.82842712 0. -4.94974747 -1.41421356]</span>
</pre></div>
</div>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">pywt</span><span class="o">.</span><span class="n">dwt_max_level</span><span class="p">(</span><span class="nb">len</span><span class="p">(</span><span class="n">x</span><span class="p">),</span> <span class="n">db1</span><span class="p">)</span>
<span class="go">3</span>
</pre></div>
</div>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">cA2</span><span class="p">,</span> <span class="n">cD2</span><span class="p">,</span> <span class="n">cD1</span> <span class="o">=</span> <span class="n">pywt</span><span class="o">.</span><span class="n">wavedec</span><span class="p">(</span><span class="n">x</span><span class="p">,</span> <span class="n">db1</span><span class="p">,</span> <span class="n">mode</span><span class="o">=</span><span class="s">'cpd'</span><span class="p">,</span> <span class="n">level</span><span class="o">=</span><span class="mi">2</span><span class="p">)</span>
</pre></div>
</div>
</div>
<div class="section" id="multilevel-idwt-reconstruction">
<h2>Multilevel IDWT reconstruction<a class="headerlink" href="#multilevel-idwt-reconstruction" title="Permalink to this headline">¶</a></h2>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">coeffs</span> <span class="o">=</span> <span class="n">pywt</span><span class="o">.</span><span class="n">wavedec</span><span class="p">(</span><span class="n">x</span><span class="p">,</span> <span class="n">db1</span><span class="p">)</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">pywt</span><span class="o">.</span><span class="n">waverec</span><span class="p">(</span><span class="n">coeffs</span><span class="p">,</span> <span class="n">db1</span><span class="p">)</span>
<span class="go">[ 3. 7. 1. 1. -2. 5. 4. 6.]</span>
</pre></div>
</div>
</div>
<div class="section" id="multilevel-swt-decomposition">
<h2>Multilevel SWT decomposition<a class="headerlink" href="#multilevel-swt-decomposition" title="Permalink to this headline">¶</a></h2>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">x</span> <span class="o">=</span> <span class="p">[</span><span class="mi">3</span><span class="p">,</span> <span class="mi">7</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="o">-</span><span class="mi">2</span><span class="p">,</span> <span class="mi">6</span><span class="p">,</span> <span class="mi">4</span><span class="p">,</span> <span class="mi">6</span><span class="p">]</span>
<span class="gp">>>> </span><span class="p">(</span><span class="n">cA2</span><span class="p">,</span> <span class="n">cD2</span><span class="p">),</span> <span class="p">(</span><span class="n">cA1</span><span class="p">,</span> <span class="n">cD1</span><span class="p">)</span> <span class="o">=</span> <span class="n">pywt</span><span class="o">.</span><span class="n">swt</span><span class="p">(</span><span class="n">x</span><span class="p">,</span> <span class="n">db1</span><span class="p">,</span> <span class="n">level</span><span class="o">=</span><span class="mi">2</span><span class="p">)</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">cA1</span>
<span class="go">[ 7.07106781 5.65685425 2.82842712 0.70710678 2.82842712 7.07106781</span>
<span class="go"> 7.07106781 6.36396103]</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">cD1</span>
<span class="go">[-2.82842712 4.24264069 -1.41421356 3.53553391 -5.65685425 1.41421356</span>
<span class="go"> -1.41421356 2.12132034]</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">cA2</span>
<span class="go">[ 7. 4.5 4. 5.5 7. 9.5 10. 8.5]</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">cD2</span>
<span class="go">[ 3. 3.5 0. -4.5 -3. 0.5 0. 0.5]</span>
</pre></div>
</div>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="p">[(</span><span class="n">cA2</span><span class="p">,</span> <span class="n">cD2</span><span class="p">)]</span> <span class="o">=</span> <span class="n">pywt</span><span class="o">.</span><span class="n">swt</span><span class="p">(</span><span class="n">cA1</span><span class="p">,</span> <span class="n">db1</span><span class="p">,</span> <span class="n">level</span><span class="o">=</span><span class="mi">1</span><span class="p">,</span> <span class="n">start_level</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">cA2</span>
<span class="go">[ 7. 4.5 4. 5.5 7. 9.5 10. 8.5]</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">cD2</span>
<span class="go">[ 3. 3.5 0. -4.5 -3. 0.5 0. 0.5]</span>
</pre></div>
</div>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">coeffs</span> <span class="o">=</span> <span class="n">pywt</span><span class="o">.</span><span class="n">swt</span><span class="p">(</span><span class="n">x</span><span class="p">,</span> <span class="n">db1</span><span class="p">)</span>
<span class="gp">>>> </span><span class="nb">len</span><span class="p">(</span><span class="n">coeffs</span><span class="p">)</span>
<span class="go">3</span>
<span class="gp">>>> </span><span class="n">pywt</span><span class="o">.</span><span class="n">swt_max_level</span><span class="p">(</span><span class="nb">len</span><span class="p">(</span><span class="n">x</span><span class="p">))</span>
<span class="go">3</span>
</pre></div>
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<li><a class="reference external" href="#multilevel-dwt-decomposition">Multilevel DWT decomposition</a></li>
<li><a class="reference external" href="#multilevel-idwt-reconstruction">Multilevel IDWT reconstruction</a></li>
<li><a class="reference external" href="#multilevel-swt-decomposition">Multilevel SWT decomposition</a></li>
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