>,
  <span class='kw'>ylim</span> <span class='kw'>=</span> <span class='kw'>NULL</span>,
  <span class='kw'>padding_factor</span> <span class='kw'>=</span> <span class='fl'>0.07</span>,
  <span class='kw'>xgrid</span> <span class='kw'>=</span> <span class='fl'>TRUE</span>,
  <span class='kw'>ygrid</span> <span class='kw'>=</span> <span class='fl'>TRUE</span>,
  <span class='kw'>xaxes</span> <span class='kw'>=</span> <span class='st'>"below"</span>,
  <span class='kw'>yaxes</span> <span class='kw'>=</span> 