'>nd</span><span class='op'>$</span><span class='va'>t1</span> <span class='op'>&lt;-</span> <span class='va'>nd.splines</span><span class='op'>[</span>, <span class='fl'>1</span><span class='op'>]</span>
<span class='va'>nd</span><span class='op'>$</span><span class='va'>t2</span> <span class='op'>&lt;-</span> <span class='va'>nd.splines</span><span class='op'>[</span>, <span class='fl'>2</span><span class='op'>]</span>
<span class='va'>nd</span><span class='op'>$</span><span class='va'>t3</span> <span cla