"0" or "+0" and negative
        zero as "-0". The string representation of positive zero can be
        controlled with the <code class="computeroutput"><span class="identifier">showpos</span></code>
        and <code class="computeroutput"><span class="identifier">noshowpos</span></code> manipulators.
      </p>
<p>
        The <code class="computeroutput"><span class="identifier">signed_zero</span> <span class="identifier">flag</span></code>
        has no effect with the input facet <code class="compute