specified here)</p></li>
<li><p><code>"approxML"</code> as <code>"approx"</code>,
except that a mixed layer is assumed to apply above the top data value; this
is done by setting the <code>yleft</code> argument to <code><a href="https://rdrr.io/r/stats/approxfun.html" class="external-link">approx()</a></code>, and
by calling that function with <code>rule=c(2, 1))</code></p></li>
<li><p><code>"lm"</code> (based on local
regression, with <code>e</code> setting the size of the local region);</p></li>
<li><p><co