span class="va">xspline_points</span>,
      <span class="kw">function</span><span class="op">(</span><span class="va">pts</span><span class="op">)</span> <span class="fu"><a href="https://rdrr.io/r/base/numeric.html">as.numeric</a></span><span class="op">(</span><span class="va">pts</span><span class="op">$</span><span class="va">x</span><span class="op">)</span>
    <span class="op">)</span><span class="op">)</span><span class="op">)</span>
    <span class="va">yrange_old</span> <span class="op">&lt;-</sp