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<a href="#define-members">Macros</a> &#124;
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<div class="title">durand_kerner_roots.cpp File Reference</div> </div>
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<p>Compute all possible approximate roots of any given polynomial using <a href="https://en.wikipedia.org/wiki/Durand%E2%80%93Kerner_method">Durand Kerner algorithm</a>
<a href="#details">More...</a></p>
<div class="textblock"><code>#include &lt;algorithm&gt;</code><br />
<code>#include &lt;cassert&gt;</code><br />
<code>#include &lt;cmath&gt;</code><br />
<code>#include &lt;complex&gt;</code><br />
<code>#include &lt;cstdlib&gt;</code><br />
<code>#include &lt;ctime&gt;</code><br />
<code>#include &lt;fstream&gt;</code><br />
<code>#include &lt;iostream&gt;</code><br />
<code>#include &lt;valarray&gt;</code><br />
</div><div class="textblock"><div class="dynheader">
Include dependency graph for durand_kerner_roots.cpp:</div>
<div class="dyncontent">
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Macros</h2></td></tr>
<tr class="memitem:af270a96662132d0385cb6b4637c5a689"><td class="memItemLeft" align="right" valign="top">#define&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../da/df2/durand__kerner__roots_8cpp.html#af270a96662132d0385cb6b4637c5a689">ACCURACY</a>&#160;&#160;&#160;1e-10</td></tr>
<tr class="separator:af270a96662132d0385cb6b4637c5a689"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a212979f5fc9dcf0a420e90b9b21d780a"><td class="memItemLeft" align="right" valign="top"><a id="a212979f5fc9dcf0a420e90b9b21d780a"></a>
#define&#160;</td><td class="memItemRight" valign="bottom"><b>MAX_BUFF_SIZE</b>&#160;&#160;&#160;50</td></tr>
<tr class="separator:a212979f5fc9dcf0a420e90b9b21d780a"><td class="memSeparator" colspan="2">&#160;</td></tr>
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Functions</h2></td></tr>
<tr class="memitem:a51637ff89e55ca749993d3e84b95d153"><td class="memItemLeft" align="right" valign="top"><a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex</a>&lt; double &gt;&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../da/df2/durand__kerner__roots_8cpp.html#a51637ff89e55ca749993d3e84b95d153">poly_function</a> (const <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/valarray.html">std::valarray</a>&lt; double &gt; &amp;coeffs, <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex</a>&lt; double &gt; x)</td></tr>
<tr class="separator:a51637ff89e55ca749993d3e84b95d153"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a3bada3e58ad8d1b00918db2ffe83a740"><td class="memItemLeft" align="right" valign="top">const char *&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../da/df2/durand__kerner__roots_8cpp.html#a3bada3e58ad8d1b00918db2ffe83a740">complex_str</a> (const <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex</a>&lt; double &gt; &amp;x)</td></tr>
<tr class="separator:a3bada3e58ad8d1b00918db2ffe83a740"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a024b8bc4755863315456d573a6732377"><td class="memItemLeft" align="right" valign="top">bool&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../da/df2/durand__kerner__roots_8cpp.html#a024b8bc4755863315456d573a6732377">check_termination</a> (long double delta)</td></tr>
<tr class="separator:a024b8bc4755863315456d573a6732377"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:ac38b9cfd2a39d856e0feba3b5d241ded"><td class="memItemLeft" align="right" valign="top"><a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/utility/pair.html">std::pair</a>&lt; uint32_t, double &gt;&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../da/df2/durand__kerner__roots_8cpp.html#ac38b9cfd2a39d856e0feba3b5d241ded">durand_kerner_algo</a> (const <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/valarray.html">std::valarray</a>&lt; double &gt; &amp;coeffs, <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/valarray.html">std::valarray</a>&lt; <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex</a>&lt; double &gt;&gt; *roots, bool write_log=false)</td></tr>
<tr class="separator:ac38b9cfd2a39d856e0feba3b5d241ded"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a1440a7779ac56f47a3f355ce4a8c7da0"><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../da/df2/durand__kerner__roots_8cpp.html#a1440a7779ac56f47a3f355ce4a8c7da0">test1</a> ()</td></tr>
<tr class="separator:a1440a7779ac56f47a3f355ce4a8c7da0"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a0283886819c7c140a023582b7269e2d0"><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../da/df2/durand__kerner__roots_8cpp.html#a0283886819c7c140a023582b7269e2d0">test2</a> ()</td></tr>
<tr class="separator:a0283886819c7c140a023582b7269e2d0"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a3c04138a5bfe5d72780bb7e82a18e627"><td class="memItemLeft" align="right" valign="top"><a id="a3c04138a5bfe5d72780bb7e82a18e627"></a>
int&#160;</td><td class="memItemRight" valign="bottom"><b>main</b> (int argc, char **argv)</td></tr>
<tr class="separator:a3c04138a5bfe5d72780bb7e82a18e627"><td class="memSeparator" colspan="2">&#160;</td></tr>
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<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><p>Compute all possible approximate roots of any given polynomial using <a href="https://en.wikipedia.org/wiki/Durand%E2%80%93Kerner_method">Durand Kerner algorithm</a> </p>
<dl class="section author"><dt>Author</dt><dd><a href="https://github.com/kvedala">Krishna Vedala</a></dd></dl>
<p>Test the algorithm online: <a href="https://gist.github.com/kvedala/27f1b0b6502af935f6917673ec43bcd7">https://gist.github.com/kvedala/27f1b0b6502af935f6917673ec43bcd7</a></p>
<p>Try the highly unstable Wilkinson's polynomial: </p><div class="fragment"><div class="line">./<a class="code" href="../../d1/de0/namespacenumerical__methods.html">numerical_methods</a>/durand_kerner_roots 1 -210 20615 -1256850 53327946</div>
<div class="line">-1672280820 40171771630 -756111184500 11310276995381 -135585182899530</div>
<div class="line">1307535010540395 -10142299865511450 63030812099294896 -311333643161390640</div>
<div class="line">1206647803780373360 -3599979517947607200 8037811822645051776</div>
<div class="line">-12870931245150988800 13803759753640704000 -8752948036761600000</div>
<div class="line">2432902008176640000</div>
</div><!-- fragment --><p>Sample implementation results to compute approximate roots of the equation \(x^4-1=0\):<br />
<img src="https://raw.githubusercontent.com/TheAlgorithms/C-Plus-Plus/docs/images/numerical_methods/durand_kerner_error.svg" alt="Error evolution during root approximations computed every
iteration." style="pointer-events: none;" width="400" class="inline"/> <img src="https://raw.githubusercontent.com/TheAlgorithms/C-Plus-Plus/docs/images/numerical_methods/durand_kerner_roots.svg" alt="Roots evolution - shows the initial approximation of the
roots and their convergence to a final approximation along with the iterative
approximations" style="pointer-events: none;" width="400" class="inline"/> </p>
</div><h2 class="groupheader">Macro Definition Documentation</h2>
<a id="af270a96662132d0385cb6b4637c5a689"></a>
<h2 class="memtitle"><span class="permalink"><a href="#af270a96662132d0385cb6b4637c5a689">&#9670;&nbsp;</a></span>ACCURACY</h2>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">#define ACCURACY&#160;&#160;&#160;1e-10</td>
</tr>
</table>
</div><div class="memdoc">
<p>maximum accuracy limit </p>
</div>
</div>
<h2 class="groupheader">Function Documentation</h2>
<a id="a024b8bc4755863315456d573a6732377"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a024b8bc4755863315456d573a6732377">&#9670;&nbsp;</a></span>check_termination()</h2>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">bool check_termination </td>
<td>(</td>
<td class="paramtype">long double&#160;</td>
<td class="paramname"><em>delta</em></td><td>)</td>
<td></td>
</tr>
</table>
</div><div class="memdoc">
<p>check for termination condition </p><dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in]</td><td class="paramname">delta</td><td>point at which to evaluate the polynomial </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd><code>false</code> if termination not reached </dd>
<dd>
<code>true</code> if termination reached </dd></dl>
<div class="fragment"><div class="line"><a name="l00091"></a><span class="lineno"> 91</span>&#160; {</div>
<div class="line"><a name="l00092"></a><span class="lineno"> 92</span>&#160; <span class="keyword">static</span> <span class="keywordtype">long</span> <span class="keywordtype">double</span> past_delta = INFINITY;</div>
<div class="line"><a name="l00093"></a><span class="lineno"> 93</span>&#160; <span class="keywordflow">if</span> (std::abs(past_delta - delta) &lt;= <a class="code" href="../../da/df2/durand__kerner__roots_8cpp.html#af270a96662132d0385cb6b4637c5a689">ACCURACY</a> || delta &lt; <a class="code" href="../../da/df2/durand__kerner__roots_8cpp.html#af270a96662132d0385cb6b4637c5a689">ACCURACY</a>)</div>
<div class="line"><a name="l00094"></a><span class="lineno"> 94</span>&#160; <span class="keywordflow">return</span> <span class="keyword">true</span>;</div>
<div class="line"><a name="l00095"></a><span class="lineno"> 95</span>&#160; past_delta = delta;</div>
<div class="line"><a name="l00096"></a><span class="lineno"> 96</span>&#160; <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
<div class="line"><a name="l00097"></a><span class="lineno"> 97</span>&#160;}</div>
</div><!-- fragment -->
</div>
</div>
<a id="a3bada3e58ad8d1b00918db2ffe83a740"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a3bada3e58ad8d1b00918db2ffe83a740">&#9670;&nbsp;</a></span>complex_str()</h2>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">const char* complex_str </td>
<td>(</td>
<td class="paramtype">const <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex</a>&lt; double &gt; &amp;&#160;</td>
<td class="paramname"><em>x</em></td><td>)</td>
<td></td>
</tr>
</table>
</div><div class="memdoc">
<p>create a textual form of complex number </p><dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in]</td><td class="paramname">x</td><td>point at which to evaluate the polynomial </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>pointer to converted string </dd></dl>
<div class="fragment"><div class="line"><a name="l00076"></a><span class="lineno"> 76</span>&#160; {</div>
<div class="line"><a name="l00077"></a><span class="lineno"> 77</span>&#160;<span class="preprocessor">#define MAX_BUFF_SIZE 50</span></div>
<div class="line"><a name="l00078"></a><span class="lineno"> 78</span>&#160; <span class="keyword">static</span> <span class="keywordtype">char</span> msg[MAX_BUFF_SIZE];</div>
<div class="line"><a name="l00079"></a><span class="lineno"> 79</span>&#160; </div>
<div class="line"><a name="l00080"></a><span class="lineno"> 80</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/c/fprintf.html">std::snprintf</a>(msg, MAX_BUFF_SIZE, <span class="stringliteral">&quot;% 7.04g%+7.04gj&quot;</span>, x.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex/real.html">real</a>(), x.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex/imag.html">imag</a>());</div>
<div class="line"><a name="l00081"></a><span class="lineno"> 81</span>&#160; </div>
<div class="line"><a name="l00082"></a><span class="lineno"> 82</span>&#160; <span class="keywordflow">return</span> msg;</div>
<div class="line"><a name="l00083"></a><span class="lineno"> 83</span>&#160;}</div>
</div><!-- fragment -->
</div>
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<a id="ac38b9cfd2a39d856e0feba3b5d241ded"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ac38b9cfd2a39d856e0feba3b5d241ded">&#9670;&nbsp;</a></span>durand_kerner_algo()</h2>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname"><a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/utility/pair.html">std::pair</a>&lt;uint32_t, double&gt; durand_kerner_algo </td>
<td>(</td>
<td class="paramtype">const <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/valarray.html">std::valarray</a>&lt; double &gt; &amp;&#160;</td>
<td class="paramname"><em>coeffs</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/valarray.html">std::valarray</a>&lt; <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex</a>&lt; double &gt;&gt; *&#160;</td>
<td class="paramname"><em>roots</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">bool&#160;</td>
<td class="paramname"><em>write_log</em> = <code>false</code>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<p>Implements Durand Kerner iterative algorithm to compute all roots of a polynomial.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in]</td><td class="paramname">coeffs</td><td>coefficients of the polynomial </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">roots</td><td>the computed roots of the polynomial </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">write_log</td><td>flag whether to save the log file (default = <code>false</code>) </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>pair of values - number of iterations taken and final accuracy achieved </dd></dl>
<div class="fragment"><div class="line"><a name="l00111"></a><span class="lineno"> 111</span>&#160; {</div>
<div class="line"><a name="l00112"></a><span class="lineno"> 112</span>&#160; <span class="keywordtype">long</span> <span class="keywordtype">double</span> tol_condition = 1;</div>
<div class="line"><a name="l00113"></a><span class="lineno"> 113</span>&#160; uint32_t iter = 0;</div>
<div class="line"><a name="l00114"></a><span class="lineno"> 114</span>&#160; <span class="keywordtype">int</span> n;</div>
<div class="line"><a name="l00115"></a><span class="lineno"> 115</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ofstream.html">std::ofstream</a> log_file;</div>
<div class="line"><a name="l00116"></a><span class="lineno"> 116</span>&#160; </div>
<div class="line"><a name="l00117"></a><span class="lineno"> 117</span>&#160; <span class="keywordflow">if</span> (write_log) {</div>
<div class="line"><a name="l00118"></a><span class="lineno"> 118</span>&#160; <span class="comment">/*</span></div>
<div class="line"><a name="l00119"></a><span class="lineno"> 119</span>&#160;<span class="comment"> * store intermediate values to a CSV file</span></div>
<div class="line"><a name="l00120"></a><span class="lineno"> 120</span>&#160;<span class="comment"> */</span></div>
<div class="line"><a name="l00121"></a><span class="lineno"> 121</span>&#160; log_file.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ofstream/open.html">open</a>(<span class="stringliteral">&quot;durand_kerner.log.csv&quot;</span>);</div>
<div class="line"><a name="l00122"></a><span class="lineno"> 122</span>&#160; <span class="keywordflow">if</span> (!log_file.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ofstream/is_open.html">is_open</a>()) {</div>
<div class="line"><a name="l00123"></a><span class="lineno"> 123</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/c/perror.html">perror</a>(<span class="stringliteral">&quot;Unable to create a storage log file!&quot;</span>);</div>
<div class="line"><a name="l00124"></a><span class="lineno"> 124</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/utility/program/exit.html">std::exit</a>(EXIT_FAILURE);</div>
<div class="line"><a name="l00125"></a><span class="lineno"> 125</span>&#160; }</div>
<div class="line"><a name="l00126"></a><span class="lineno"> 126</span>&#160; log_file &lt;&lt; <span class="stringliteral">&quot;iter#,&quot;</span>;</div>
<div class="line"><a name="l00127"></a><span class="lineno"> 127</span>&#160; </div>
<div class="line"><a name="l00128"></a><span class="lineno"> 128</span>&#160; <span class="keywordflow">for</span> (n = 0; n &lt; roots-&gt;size(); n++) log_file &lt;&lt; <span class="stringliteral">&quot;root_&quot;</span> &lt;&lt; n &lt;&lt; <span class="stringliteral">&quot;,&quot;</span>;</div>
<div class="line"><a name="l00129"></a><span class="lineno"> 129</span>&#160; </div>
<div class="line"><a name="l00130"></a><span class="lineno"> 130</span>&#160; log_file &lt;&lt; <span class="stringliteral">&quot;avg. correction&quot;</span>;</div>
<div class="line"><a name="l00131"></a><span class="lineno"> 131</span>&#160; log_file &lt;&lt; <span class="stringliteral">&quot;\n0,&quot;</span>;</div>
<div class="line"><a name="l00132"></a><span class="lineno"> 132</span>&#160; <span class="keywordflow">for</span> (n = 0; n &lt; roots-&gt;size(); n++)</div>
<div class="line"><a name="l00133"></a><span class="lineno"> 133</span>&#160; log_file &lt;&lt; <a class="code" href="../../da/df2/durand__kerner__roots_8cpp.html#a3bada3e58ad8d1b00918db2ffe83a740">complex_str</a>((*roots)[n]) &lt;&lt; <span class="stringliteral">&quot;,&quot;</span>;</div>
<div class="line"><a name="l00134"></a><span class="lineno"> 134</span>&#160; }</div>
<div class="line"><a name="l00135"></a><span class="lineno"> 135</span>&#160; </div>
<div class="line"><a name="l00136"></a><span class="lineno"> 136</span>&#160; <span class="keywordtype">bool</span> break_loop = <span class="keyword">false</span>;</div>
<div class="line"><a name="l00137"></a><span class="lineno"> 137</span>&#160; <span class="keywordflow">while</span> (!<a class="code" href="../../da/df2/durand__kerner__roots_8cpp.html#a024b8bc4755863315456d573a6732377">check_termination</a>(tol_condition) &amp;&amp; iter &lt; INT16_MAX &amp;&amp;</div>
<div class="line"><a name="l00138"></a><span class="lineno"> 138</span>&#160; !break_loop) {</div>
<div class="line"><a name="l00139"></a><span class="lineno"> 139</span>&#160; tol_condition = 0;</div>
<div class="line"><a name="l00140"></a><span class="lineno"> 140</span>&#160; iter++;</div>
<div class="line"><a name="l00141"></a><span class="lineno"> 141</span>&#160; break_loop = <span class="keyword">false</span>;</div>
<div class="line"><a name="l00142"></a><span class="lineno"> 142</span>&#160; </div>
<div class="line"><a name="l00143"></a><span class="lineno"> 143</span>&#160; <span class="keywordflow">if</span> (log_file.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ofstream/is_open.html">is_open</a>())</div>
<div class="line"><a name="l00144"></a><span class="lineno"> 144</span>&#160; log_file &lt;&lt; <span class="stringliteral">&quot;\n&quot;</span> &lt;&lt; iter &lt;&lt; <span class="stringliteral">&quot;,&quot;</span>;</div>
<div class="line"><a name="l00145"></a><span class="lineno"> 145</span>&#160; </div>
<div class="line"><a name="l00146"></a><span class="lineno"> 146</span>&#160;<span class="preprocessor">#ifdef _OPENMP</span></div>
<div class="line"><a name="l00147"></a><span class="lineno"> 147</span>&#160;<span class="preprocessor">#pragma omp parallel for shared(break_loop, tol_condition)</span></div>
<div class="line"><a name="l00148"></a><span class="lineno"> 148</span>&#160;<span class="preprocessor">#endif</span></div>
<div class="line"><a name="l00149"></a><span class="lineno"> 149</span>&#160; <span class="keywordflow">for</span> (n = 0; n &lt; roots-&gt;size(); n++) {</div>
<div class="line"><a name="l00150"></a><span class="lineno"> 150</span>&#160; <span class="keywordflow">if</span> (break_loop)</div>
<div class="line"><a name="l00151"></a><span class="lineno"> 151</span>&#160; <span class="keywordflow">continue</span>;</div>
<div class="line"><a name="l00152"></a><span class="lineno"> 152</span>&#160; </div>
<div class="line"><a name="l00153"></a><span class="lineno"> 153</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex&lt;double&gt;</a> numerator, denominator;</div>
<div class="line"><a name="l00154"></a><span class="lineno"> 154</span>&#160; numerator = <a class="code" href="../../da/df2/durand__kerner__roots_8cpp.html#a51637ff89e55ca749993d3e84b95d153">poly_function</a>(coeffs, (*roots)[n]);</div>
<div class="line"><a name="l00155"></a><span class="lineno"> 155</span>&#160; denominator = 1.0;</div>
<div class="line"><a name="l00156"></a><span class="lineno"> 156</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i &lt; roots-&gt;size(); i++)</div>
<div class="line"><a name="l00157"></a><span class="lineno"> 157</span>&#160; <span class="keywordflow">if</span> (i != n)</div>
<div class="line"><a name="l00158"></a><span class="lineno"> 158</span>&#160; denominator *= (*roots)[n] - (*roots)[i];</div>
<div class="line"><a name="l00159"></a><span class="lineno"> 159</span>&#160; </div>
<div class="line"><a name="l00160"></a><span class="lineno"> 160</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex&lt;long double&gt;</a> delta = numerator / denominator;</div>
<div class="line"><a name="l00161"></a><span class="lineno"> 161</span>&#160; </div>
<div class="line"><a name="l00162"></a><span class="lineno"> 162</span>&#160; <span class="keywordflow">if</span> (<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/math/isnan.html">std::isnan</a>(std::abs(delta)) || <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/math/isinf.html">std::isinf</a>(std::abs(delta))) {</div>
<div class="line"><a name="l00163"></a><span class="lineno"> 163</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cerr</a> &lt;&lt; <span class="stringliteral">&quot;\n\nOverflow/underrun error - got value = &quot;</span></div>
<div class="line"><a name="l00164"></a><span class="lineno"> 164</span>&#160; &lt;&lt; std::abs(delta) &lt;&lt; <span class="stringliteral">&quot;\n&quot;</span>;</div>
<div class="line"><a name="l00165"></a><span class="lineno"> 165</span>&#160; <span class="comment">// return std::pair&lt;uint32_t, double&gt;(iter, tol_condition);</span></div>
<div class="line"><a name="l00166"></a><span class="lineno"> 166</span>&#160; break_loop = <span class="keyword">true</span>;</div>
<div class="line"><a name="l00167"></a><span class="lineno"> 167</span>&#160; }</div>
<div class="line"><a name="l00168"></a><span class="lineno"> 168</span>&#160; </div>
<div class="line"><a name="l00169"></a><span class="lineno"> 169</span>&#160; (*roots)[n] -= delta;</div>
<div class="line"><a name="l00170"></a><span class="lineno"> 170</span>&#160; </div>
<div class="line"><a name="l00171"></a><span class="lineno"> 171</span>&#160;<span class="preprocessor">#ifdef _OPENMP</span></div>
<div class="line"><a name="l00172"></a><span class="lineno"> 172</span>&#160;<span class="preprocessor">#pragma omp critical</span></div>
<div class="line"><a name="l00173"></a><span class="lineno"> 173</span>&#160;<span class="preprocessor">#endif</span></div>
<div class="line"><a name="l00174"></a><span class="lineno"> 174</span>&#160; tol_condition = <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/algorithm/max.html">std::max</a>(tol_condition, std::abs(std::abs(delta)));</div>
<div class="line"><a name="l00175"></a><span class="lineno"> 175</span>&#160; }</div>
<div class="line"><a name="l00176"></a><span class="lineno"> 176</span>&#160; <span class="comment">// tol_condition /= (degree - 1);</span></div>
<div class="line"><a name="l00177"></a><span class="lineno"> 177</span>&#160; </div>
<div class="line"><a name="l00178"></a><span class="lineno"> 178</span>&#160; <span class="keywordflow">if</span> (break_loop)</div>
<div class="line"><a name="l00179"></a><span class="lineno"> 179</span>&#160; <span class="keywordflow">break</span>;</div>
<div class="line"><a name="l00180"></a><span class="lineno"> 180</span>&#160; </div>
<div class="line"><a name="l00181"></a><span class="lineno"> 181</span>&#160; <span class="keywordflow">if</span> (log_file.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ofstream/is_open.html">is_open</a>()) {</div>
<div class="line"><a name="l00182"></a><span class="lineno"> 182</span>&#160; <span class="keywordflow">for</span> (n = 0; n &lt; roots-&gt;size(); n++)</div>
<div class="line"><a name="l00183"></a><span class="lineno"> 183</span>&#160; log_file &lt;&lt; <a class="code" href="../../da/df2/durand__kerner__roots_8cpp.html#a3bada3e58ad8d1b00918db2ffe83a740">complex_str</a>((*roots)[n]) &lt;&lt; <span class="stringliteral">&quot;,&quot;</span>;</div>
<div class="line"><a name="l00184"></a><span class="lineno"> 184</span>&#160; }</div>
<div class="line"><a name="l00185"></a><span class="lineno"> 185</span>&#160; </div>
<div class="line"><a name="l00186"></a><span class="lineno"> 186</span>&#160;<span class="preprocessor">#if defined(DEBUG) || !defined(NDEBUG)</span></div>
<div class="line"><a name="l00187"></a><span class="lineno"> 187</span>&#160; <span class="keywordflow">if</span> (iter % 500 == 0) {</div>
<div class="line"><a name="l00188"></a><span class="lineno"> 188</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;Iter: &quot;</span> &lt;&lt; iter &lt;&lt; <span class="stringliteral">&quot;\t&quot;</span>;</div>
<div class="line"><a name="l00189"></a><span class="lineno"> 189</span>&#160; <span class="keywordflow">for</span> (n = 0; n &lt; roots-&gt;size(); n++)</div>
<div class="line"><a name="l00190"></a><span class="lineno"> 190</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;\t&quot;</span> &lt;&lt; <a class="code" href="../../da/df2/durand__kerner__roots_8cpp.html#a3bada3e58ad8d1b00918db2ffe83a740">complex_str</a>((*roots)[n]);</div>
<div class="line"><a name="l00191"></a><span class="lineno"> 191</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;\t\tabsolute average change: &quot;</span> &lt;&lt; tol_condition</div>
<div class="line"><a name="l00192"></a><span class="lineno"> 192</span>&#160; &lt;&lt; <span class="stringliteral">&quot;\n&quot;</span>;</div>
<div class="line"><a name="l00193"></a><span class="lineno"> 193</span>&#160; }</div>
<div class="line"><a name="l00194"></a><span class="lineno"> 194</span>&#160;<span class="preprocessor">#endif</span></div>
<div class="line"><a name="l00195"></a><span class="lineno"> 195</span>&#160; </div>
<div class="line"><a name="l00196"></a><span class="lineno"> 196</span>&#160; <span class="keywordflow">if</span> (log_file.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ofstream/is_open.html">is_open</a>())</div>
<div class="line"><a name="l00197"></a><span class="lineno"> 197</span>&#160; log_file &lt;&lt; tol_condition;</div>
<div class="line"><a name="l00198"></a><span class="lineno"> 198</span>&#160; }</div>
<div class="line"><a name="l00199"></a><span class="lineno"> 199</span>&#160; </div>
<div class="line"><a name="l00200"></a><span class="lineno"> 200</span>&#160; <span class="keywordflow">return</span> <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/utility/pair.html">std::pair&lt;uint32_t, long double&gt;</a>(iter, tol_condition);</div>
<div class="line"><a name="l00201"></a><span class="lineno"> 201</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a51637ff89e55ca749993d3e84b95d153">&#9670;&nbsp;</a></span>poly_function()</h2>
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<table class="memname">
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<td class="memname"><a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex</a>&lt;double&gt; poly_function </td>
<td>(</td>
<td class="paramtype">const <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/valarray.html">std::valarray</a>&lt; double &gt; &amp;&#160;</td>
<td class="paramname"><em>coeffs</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex</a>&lt; double &gt;&#160;</td>
<td class="paramname"><em>x</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
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<p>Evaluate the value of a polynomial with given coefficients </p><dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[in]</td><td class="paramname">coeffs</td><td>coefficients of the polynomial </td></tr>
<tr><td class="paramdir">[in]</td><td class="paramname">x</td><td>point at which to evaluate the polynomial </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>\(f(x)\) </dd></dl>
<div class="fragment"><div class="line"><a name="l00054"></a><span class="lineno"> 54</span>&#160; {</div>
<div class="line"><a name="l00055"></a><span class="lineno"> 55</span>&#160; <span class="keywordtype">double</span> real = 0.f, imag = 0.f;</div>
<div class="line"><a name="l00056"></a><span class="lineno"> 56</span>&#160; <span class="keywordtype">int</span> n;</div>
<div class="line"><a name="l00057"></a><span class="lineno"> 57</span>&#160; </div>
<div class="line"><a name="l00058"></a><span class="lineno"> 58</span>&#160; <span class="comment">// #ifdef _OPENMP</span></div>
<div class="line"><a name="l00059"></a><span class="lineno"> 59</span>&#160; <span class="comment">// #pragma omp target teams distribute reduction(+ : real, imag)</span></div>
<div class="line"><a name="l00060"></a><span class="lineno"> 60</span>&#160; <span class="comment">// #endif</span></div>
<div class="line"><a name="l00061"></a><span class="lineno"> 61</span>&#160; <span class="keywordflow">for</span> (n = 0; n &lt; coeffs.size(); n++) {</div>
<div class="line"><a name="l00062"></a><span class="lineno"> 62</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex&lt;double&gt;</a> tmp =</div>
<div class="line"><a name="l00063"></a><span class="lineno"> 63</span>&#160; coeffs[n] * <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/math/pow.html">std::pow</a>(x, coeffs.size() - n - 1);</div>
<div class="line"><a name="l00064"></a><span class="lineno"> 64</span>&#160; real += tmp.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex/real.html">real</a>();</div>
<div class="line"><a name="l00065"></a><span class="lineno"> 65</span>&#160; imag += tmp.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex/imag.html">imag</a>();</div>
<div class="line"><a name="l00066"></a><span class="lineno"> 66</span>&#160; }</div>
<div class="line"><a name="l00067"></a><span class="lineno"> 67</span>&#160; </div>
<div class="line"><a name="l00068"></a><span class="lineno"> 68</span>&#160; <span class="keywordflow">return</span> <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex&lt;double&gt;</a>(real, imag);</div>
<div class="line"><a name="l00069"></a><span class="lineno"> 69</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a1440a7779ac56f47a3f355ce4a8c7da0">&#9670;&nbsp;</a></span>test1()</h2>
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<td class="memname">void test1 </td>
<td>(</td>
<td class="paramname"></td><td>)</td>
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<p>Self test the algorithm by checking the roots for \(x^2+4=0\) to which the roots are \(0 \pm 2i\) </p>
<div class="fragment"><div class="line"><a name="l00207"></a><span class="lineno"> 207</span>&#160; {</div>
<div class="line"><a name="l00208"></a><span class="lineno"> 208</span>&#160; <span class="keyword">const</span> <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/valarray.html">std::valarray&lt;double&gt;</a> coeffs = {1, 0, 4}; <span class="comment">// x^2 - 2 = 0</span></div>
<div class="line"><a name="l00209"></a><span class="lineno"> 209</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/valarray.html">std::valarray&lt;std::complex&lt;double&gt;</a>&gt; roots(2);</div>
<div class="line"><a name="l00210"></a><span class="lineno"> 210</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/valarray.html">std::valarray&lt;std::complex&lt;double&gt;</a>&gt; expected = {</div>
<div class="line"><a name="l00211"></a><span class="lineno"> 211</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex&lt;double&gt;</a>(0., 2.),</div>
<div class="line"><a name="l00212"></a><span class="lineno"> 212</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex&lt;double&gt;</a>(0., -2.) <span class="comment">// known expected roots</span></div>
<div class="line"><a name="l00213"></a><span class="lineno"> 213</span>&#160; };</div>
<div class="line"><a name="l00214"></a><span class="lineno"> 214</span>&#160; </div>
<div class="line"><a name="l00215"></a><span class="lineno"> 215</span>&#160; <span class="comment">/* initialize root approximations with random values */</span></div>
<div class="line"><a name="l00216"></a><span class="lineno"> 216</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> n = 0; n &lt; roots.size(); n++) {</div>
<div class="line"><a name="l00217"></a><span class="lineno"> 217</span>&#160; roots[n] = <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex&lt;double&gt;</a>(<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/random/rand.html">std::rand</a>() % 100, <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/random/rand.html">std::rand</a>() % 100);</div>
<div class="line"><a name="l00218"></a><span class="lineno"> 218</span>&#160; roots[n] -= 50.f;</div>
<div class="line"><a name="l00219"></a><span class="lineno"> 219</span>&#160; roots[n] /= 25.f;</div>
<div class="line"><a name="l00220"></a><span class="lineno"> 220</span>&#160; }</div>
<div class="line"><a name="l00221"></a><span class="lineno"> 221</span>&#160; </div>
<div class="line"><a name="l00222"></a><span class="lineno"> 222</span>&#160; <span class="keyword">auto</span> <a class="code" href="../../de/dc3/fibonacci__sum_8cpp.html#aadb40ac4c74a7efc0680b83eeee138aa">result</a> = <a class="code" href="../../da/df2/durand__kerner__roots_8cpp.html#ac38b9cfd2a39d856e0feba3b5d241ded">durand_kerner_algo</a>(coeffs, &amp;roots, <span class="keyword">false</span>);</div>
<div class="line"><a name="l00223"></a><span class="lineno"> 223</span>&#160; </div>
<div class="line"><a name="l00224"></a><span class="lineno"> 224</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i &lt; roots.size(); i++) {</div>
<div class="line"><a name="l00225"></a><span class="lineno"> 225</span>&#160; <span class="comment">// check if approximations are have &lt; 0.1% error with one of the</span></div>
<div class="line"><a name="l00226"></a><span class="lineno"> 226</span>&#160; <span class="comment">// expected roots</span></div>
<div class="line"><a name="l00227"></a><span class="lineno"> 227</span>&#160; <span class="keywordtype">bool</span> err1 = <span class="keyword">false</span>;</div>
<div class="line"><a name="l00228"></a><span class="lineno"> 228</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> j = 0; j &lt; roots.size(); j++)</div>
<div class="line"><a name="l00229"></a><span class="lineno"> 229</span>&#160; err1 |= std::abs(std::abs(roots[i] - expected[j])) &lt; 1e-3;</div>
<div class="line"><a name="l00230"></a><span class="lineno"> 230</span>&#160; assert(err1);</div>
<div class="line"><a name="l00231"></a><span class="lineno"> 231</span>&#160; }</div>
<div class="line"><a name="l00232"></a><span class="lineno"> 232</span>&#160; </div>
<div class="line"><a name="l00233"></a><span class="lineno"> 233</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;Test 1 passed! - &quot;</span> &lt;&lt; <a class="code" href="../../de/dc3/fibonacci__sum_8cpp.html#aadb40ac4c74a7efc0680b83eeee138aa">result</a>.first &lt;&lt; <span class="stringliteral">&quot; iterations, &quot;</span></div>
<div class="line"><a name="l00234"></a><span class="lineno"> 234</span>&#160; &lt;&lt; <a class="code" href="../../de/dc3/fibonacci__sum_8cpp.html#aadb40ac4c74a7efc0680b83eeee138aa">result</a>.second &lt;&lt; <span class="stringliteral">&quot; accuracy&quot;</span></div>
<div class="line"><a name="l00235"></a><span class="lineno"> 235</span>&#160; &lt;&lt; <span class="stringliteral">&quot;\n&quot;</span>;</div>
<div class="line"><a name="l00236"></a><span class="lineno"> 236</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a0283886819c7c140a023582b7269e2d0">&#9670;&nbsp;</a></span>test2()</h2>
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<td class="memname">void test2 </td>
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<p>Self test the algorithm by checking the roots for \(0.015625x^3-1=0\) to which the roots are \((4+0i),\,(-2\pm3.464i)\) </p>
<div class="fragment"><div class="line"><a name="l00242"></a><span class="lineno"> 242</span>&#160; {</div>
<div class="line"><a name="l00243"></a><span class="lineno"> 243</span>&#160; <span class="keyword">const</span> <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/valarray.html">std::valarray&lt;double&gt;</a> coeffs = {<span class="comment">// 0.015625 x^3 - 1 = 0</span></div>
<div class="line"><a name="l00244"></a><span class="lineno"> 244</span>&#160; 1. / 64., 0., 0., -1.};</div>
<div class="line"><a name="l00245"></a><span class="lineno"> 245</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/valarray.html">std::valarray&lt;std::complex&lt;double&gt;</a>&gt; roots(3);</div>
<div class="line"><a name="l00246"></a><span class="lineno"> 246</span>&#160; <span class="keyword">const</span> <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/valarray.html">std::valarray&lt;std::complex&lt;double&gt;</a>&gt; expected = {</div>
<div class="line"><a name="l00247"></a><span class="lineno"> 247</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex&lt;double&gt;</a>(4., 0.), <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex&lt;double&gt;</a>(-2., 3.46410162),</div>
<div class="line"><a name="l00248"></a><span class="lineno"> 248</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex&lt;double&gt;</a>(-2., -3.46410162) <span class="comment">// known expected roots</span></div>
<div class="line"><a name="l00249"></a><span class="lineno"> 249</span>&#160; };</div>
<div class="line"><a name="l00250"></a><span class="lineno"> 250</span>&#160; </div>
<div class="line"><a name="l00251"></a><span class="lineno"> 251</span>&#160; <span class="comment">/* initialize root approximations with random values */</span></div>
<div class="line"><a name="l00252"></a><span class="lineno"> 252</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> n = 0; n &lt; roots.size(); n++) {</div>
<div class="line"><a name="l00253"></a><span class="lineno"> 253</span>&#160; roots[n] = <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/complex.html">std::complex&lt;double&gt;</a>(<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/random/rand.html">std::rand</a>() % 100, <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/random/rand.html">std::rand</a>() % 100);</div>
<div class="line"><a name="l00254"></a><span class="lineno"> 254</span>&#160; roots[n] -= 50.f;</div>
<div class="line"><a name="l00255"></a><span class="lineno"> 255</span>&#160; roots[n] /= 25.f;</div>
<div class="line"><a name="l00256"></a><span class="lineno"> 256</span>&#160; }</div>
<div class="line"><a name="l00257"></a><span class="lineno"> 257</span>&#160; </div>
<div class="line"><a name="l00258"></a><span class="lineno"> 258</span>&#160; <span class="keyword">auto</span> <a class="code" href="../../de/dc3/fibonacci__sum_8cpp.html#aadb40ac4c74a7efc0680b83eeee138aa">result</a> = <a class="code" href="../../da/df2/durand__kerner__roots_8cpp.html#ac38b9cfd2a39d856e0feba3b5d241ded">durand_kerner_algo</a>(coeffs, &amp;roots, <span class="keyword">false</span>);</div>
<div class="line"><a name="l00259"></a><span class="lineno"> 259</span>&#160; </div>
<div class="line"><a name="l00260"></a><span class="lineno"> 260</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i &lt; roots.size(); i++) {</div>
<div class="line"><a name="l00261"></a><span class="lineno"> 261</span>&#160; <span class="comment">// check if approximations are have &lt; 0.1% error with one of the</span></div>
<div class="line"><a name="l00262"></a><span class="lineno"> 262</span>&#160; <span class="comment">// expected roots</span></div>
<div class="line"><a name="l00263"></a><span class="lineno"> 263</span>&#160; <span class="keywordtype">bool</span> err1 = <span class="keyword">false</span>;</div>
<div class="line"><a name="l00264"></a><span class="lineno"> 264</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> j = 0; j &lt; roots.size(); j++)</div>
<div class="line"><a name="l00265"></a><span class="lineno"> 265</span>&#160; err1 |= std::abs(std::abs(roots[i] - expected[j])) &lt; 1e-3;</div>
<div class="line"><a name="l00266"></a><span class="lineno"> 266</span>&#160; assert(err1);</div>
<div class="line"><a name="l00267"></a><span class="lineno"> 267</span>&#160; }</div>
<div class="line"><a name="l00268"></a><span class="lineno"> 268</span>&#160; </div>
<div class="line"><a name="l00269"></a><span class="lineno"> 269</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;Test 2 passed! - &quot;</span> &lt;&lt; <a class="code" href="../../de/dc3/fibonacci__sum_8cpp.html#aadb40ac4c74a7efc0680b83eeee138aa">result</a>.first &lt;&lt; <span class="stringliteral">&quot; iterations, &quot;</span></div>
<div class="line"><a name="l00270"></a><span class="lineno"> 270</span>&#160; &lt;&lt; <a class="code" href="../../de/dc3/fibonacci__sum_8cpp.html#aadb40ac4c74a7efc0680b83eeee138aa">result</a>.second &lt;&lt; <span class="stringliteral">&quot; accuracy&quot;</span></div>
<div class="line"><a name="l00271"></a><span class="lineno"> 271</span>&#160; &lt;&lt; <span class="stringliteral">&quot;\n&quot;</span>;</div>
<div class="line"><a name="l00272"></a><span class="lineno"> 272</span>&#160;}</div>
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