lass="o">.</span><span class="n">get_cell</span><span class="p">()</span><span class="o">.</span><span class="n">T</span><span class="p">,</span>
            <span class="n">positions</span><span class="o">.</span><span class="n">T</span><span class="p">)</span><span class="o">.</span><span class="n">T</span>

        <span class="k">if</span> <span class="n">wrap</span><span class="p">:</span>
            <span class="k">for</span> <span class="n">i</span><span class="p">,</span> <span class="n">periodic</