> <span class='op'>&lt;-</span> <span class='fl'>500</span>
  <span class='va'>num_chains</span> <span class='op'>&lt;-</span> <span class='fl'>64L</span>
  <span class='va'>step_size</span> <span class='op'>&lt;-</span> <span class='va'>tf</span><span class='op'>$</span><span class='fu'>fill</span><span class='op'>(</span><span class='fu'><a href='https://rdrr.io/r/base/list.html'>list</a></span><span class='op'>(</span><span class='va'>num_chains</span><span class='op'>)</span>, <span class='fl'>0.1</span