 class="identifier">size_t</span> <a class="link" href="mean.html#idm45106007712544-bb"><span class="identifier">count</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span> <span class="keyword">noexcept</span><span class="special">;</span>
  <span class="keyword">const</span> <span class="identifier">RealType</span> <span class="special">&amp;</span> <a class="link" href="mean.html#idm45106007711424-bb"><span class="identifier">value</span></a><span class