s="op">=</span> <span class="cn">NULL</span>,</span>
<span>  x2var <span class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  x2shift <span class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  xlab <span class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  ylab <span class="op">=</span> <span class="va">geneName</span>,</span>
<span>  plab <span class="op">=</span> <span class="cn">NULL</span>,</span>
<span>  title <span class="op">=</span> <span class="va">geneName</span