 class="n">sin</span><span class="p">((</span><span class="n">np</span><span class="o">.</span><span class="n">pi</span> <span class="o">*</span> <span class="n">np</span><span class="o">.</span><span class="n">arange</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="n">win_len</span><span class="p">))</span> <span class="o">/</span> <span class="n">win_len</span><span class="p">)</span> <span class="o">**</span> <span class="n">beta</span>

    <span class="k">ret