                      <span class="keywordflow">if</span> (!isReal()) throw_invalid_argument(<span class="stringliteral">&quot;A single complex number needs to be real.&quot;</span>);</div>
<div class="line"><a id="l00055" name="l00055"></a><span class="lineno">   55</span>                }</div>
<div class="line"><a id="l00056" name="l00056"></a><span class="lineno">   56</span> </div>
<div class="line"><a id="l00057" name="l00057"></a><span class="lineno">   57</span>                <a class="code hl_stru