pan class="n">arr</span><span class="p">)</span>

        <span class="n">locs</span> <span class="o">=</span> <span class="nb">len</span><span class="p">(</span><span class="n">np</span><span class="o">.</span><span class="n">where</span><span class="p">(</span><span class="n">arr</span> <span class="o">&lt;=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_period</span><span class="p">)[</span><span class="mi">0</span><span class="p">])</span>

        <span class="k">return</sp