 class="identifier">space</span><span class="special">;</span>
        <span class="keyword">using</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">phoenix</span><span class="special">::</span><span class="identifier">ref</span><span class="special">;</span>

        <span class="keyword">double</span> <span class="identifier">rN</span> <span class="special">=</span> <span class="number">0.0</span><span class="special">;</span>
        <span class="keyword"