s='op'>[</span>,<span class='fl'>3</span><span class='op'>:</span><span class='fl'>5</span><span class='op'>]</span>, splitvars<span class='op'>=</span><span class='va'>d</span><span class='op'>[</span>,<span class='fl'>1</span><span class='op'>:</span><span class='fl'>2</span><span class='op'>]</span>, 
                     method<span class='op'>=</span><span class='st'>"ctree"</span><span class='op'>)</span>

<span class='co'>## Change control arguments</span>
<span class='va'>tree4</span> <span class='o