tifier">lanczos</span><span class="special">(</span><span class="identifier">v</span><span class="special">);</span>
</pre>
<p>
      Noise-suppressing second derivatives can also be computed. The syntax is as
      follows:
    </p>
<pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special">&lt;</span><span class="keyword">double</span><span class="special">&gt;</span> <span class="identifier">v</span><span class