an><span class="p">)</span>
  <span class="n">idm</span> <span class="o">=</span> <span class="n">size</span><span class="p">(</span><span class="n">f</span><span class="p">,</span><span class="nb">dim</span><span class="o">=</span><span class="mi">2</span><span class="p">)</span>
  <span class="n">jdm</span> <span class="o">=</span> <span class="n">size</span><span class="p">(</span><span class="n">f</span><span class="p">,</span><span class="nb">dim</span><span class="o">=</span><span class="mi">3</span><