e remaining six arguments are assignable to types
<code>real</code>, <code>real</code>, <code>real[]</code>, <code>real[]</code>, and <code>int[]</code>, and</p></li>
<li><p>the fourth and fifth arguments must be expressions not containing
any variables not originating in the data or transformed data blocks.</p></li>
</ul>
<p><code>integrate_1d</code> can accept an extra argument, which, like the
fourth and fifth arguments, must be expressions free of parameter
references. This optional sixth argument must 