n class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  gformula <span class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  data <span class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  <span class="va">...</span>,</span>
<span>  <span class="va">alpha</span>,</span>
<span>  <span class="va">color</span>,</span>
<span>  <span class="va">group</span>,</span>
<span>  <span class="va">linetype</span>,</span>
<span>  <span class="va">linewidth</span>,</span>
<span>  contour 