ss="keyword">double</span> <span class="identifier">theta</span><span class="special">);</span>

<span class="comment">// [5.2.1.23] spherical Neumann functions;</span>
<span class="comment">// spherical Bessel functions (of the second kind):</span>
<span class="keyword">double</span> <span class="identifier">sph_neumann</span><span class="special">(</span><span class="keyword">unsigned</span> <span class="identifier">n</span><span class="special">,</span> <span class="keyword">double</span> <span class="id