lass='kw'>NULL</span>,
  <span class='kw'>title_wrap</span> <span class='kw'>=</span> <span class='fl'>70</span>,
  <span class='kw'>subtitle</span> <span class='kw'>=</span> <span class='kw'>NULL</span>,
  <span class='kw'>subtitle_wrap</span> <span class='kw'>=</span> <span class='fl'>80</span>,
  <span class='kw'>x_balance</span> <span class='kw'>=</span> <span class='fl'>FALSE</span>,
  <span class='kw'>x_expand</span> <span class='kw'>=</span> <span class='kw'>NULL</span>,
  <span class='kw'>x_labels</