            <span class="at">times =</span> <span class="fu">c</span>(<span class="dv">1</span>,<span class="dv">2</span>,<span class="dv">3</span>,<span class="dv">4</span>), <span class="co"># times when the covariate changes:</span></span>
<span id="cb104-5"><a href="timedep.html#cb104-5" aria-hidden="true" tabindex="-1"></a>                      <span class="at">covariates =</span> <span class="fu">list</span>(<span class="fu">list</span>(<span class="at">age=</span><span class="dv">50</span>), <span cl