TheAlgorithms-C/d5/d23/qr__decomposition_8c.html
2020-06-28 15:30:37 +00:00

225 lines
17 KiB
HTML

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "https://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<meta http-equiv="X-UA-Compatible" content="IE=9"/>
<meta name="generator" content="Doxygen 1.8.18"/>
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<title>Algorithms_in_C: numerical_methods/qr_decomposition.c File Reference</title>
<link href="../../tabs.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="../../jquery.js"></script>
<script type="text/javascript" src="../../dynsections.js"></script>
<link href="../../navtree.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="../../resize.js"></script>
<script type="text/javascript" src="../../navtreedata.js"></script>
<script type="text/javascript" src="../../navtree.js"></script>
<link href="../../search/search.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="../../search/searchdata.js"></script>
<script type="text/javascript" src="../../search/search.js"></script>
<script type="text/x-mathjax-config">
MathJax.Hub.Config({
extensions: ["tex2jax.js", "TeX/AMSmath.js", "TeX/AMSsymbols.js"],
jax: ["input/TeX","output/HTML-CSS"],
});
</script>
<script type="text/javascript" async="async" src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.7/MathJax.js?config=TeX-MML-AM_CHTML/MathJax.js"></script>
<link href="../../doxygen.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div id="top"><!-- do not remove this div, it is closed by doxygen! -->
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr style="height: 56px;">
<td id="projectalign" style="padding-left: 0.5em;">
<div id="projectname">Algorithms_in_C
&#160;<span id="projectnumber">1.0.0</span>
</div>
<div id="projectbrief">Set of algorithms implemented in C.</div>
</td>
</tr>
</tbody>
</table>
</div>
<!-- end header part -->
<!-- Generated by Doxygen 1.8.18 -->
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:cf05388f2679ee054f2beb29a391d25f4e673ac3&amp;dn=gpl-2.0.txt GPL-v2 */
var searchBox = new SearchBox("searchBox", "../../search",false,'Search');
/* @license-end */
</script>
<script type="text/javascript" src="../../menudata.js"></script>
<script type="text/javascript" src="../../menu.js"></script>
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:cf05388f2679ee054f2beb29a391d25f4e673ac3&amp;dn=gpl-2.0.txt GPL-v2 */
$(function() {
initMenu('../../',true,false,'search.php','Search');
$(document).ready(function() { init_search(); });
});
/* @license-end */</script>
<div id="main-nav"></div>
</div><!-- top -->
<div id="side-nav" class="ui-resizable side-nav-resizable">
<div id="nav-tree">
<div id="nav-tree-contents">
<div id="nav-sync" class="sync"></div>
</div>
</div>
<div id="splitbar" style="-moz-user-select:none;"
class="ui-resizable-handle">
</div>
</div>
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:cf05388f2679ee054f2beb29a391d25f4e673ac3&amp;dn=gpl-2.0.txt GPL-v2 */
$(document).ready(function(){initNavTree('d5/d23/qr__decomposition_8c.html','../../'); initResizable(); });
/* @license-end */
</script>
<div id="doc-content">
<!-- window showing the filter options -->
<div id="MSearchSelectWindow"
onmouseover="return searchBox.OnSearchSelectShow()"
onmouseout="return searchBox.OnSearchSelectHide()"
onkeydown="return searchBox.OnSearchSelectKey(event)">
</div>
<!-- iframe showing the search results (closed by default) -->
<div id="MSearchResultsWindow">
<iframe src="javascript:void(0)" frameborder="0"
name="MSearchResults" id="MSearchResults">
</iframe>
</div>
<div class="header">
<div class="summary">
<a href="#func-members">Functions</a> </div>
<div class="headertitle">
<div class="title">qr_decomposition.c File Reference</div> </div>
</div><!--header-->
<div class="contents">
<p>Program to compute the <a href="https://en.wikipedia.org/wiki/QR_decomposition">QR decomposition</a> of a given matrix.
<a href="#details">More...</a></p>
<div class="textblock"><code>#include &lt;math.h&gt;</code><br />
<code>#include &lt;stdio.h&gt;</code><br />
<code>#include &lt;stdlib.h&gt;</code><br />
<code>#include &lt;time.h&gt;</code><br />
<code>#include &quot;<a class="el" href="../../d4/d68/qr__decompose_8h_source.html">qr_decompose.h</a>&quot;</code><br />
</div><div class="textblock"><div class="dynheader">
Include dependency graph for qr_decomposition.c:</div>
<div class="dyncontent">
<div class="center"><iframe scrolling="no" frameborder="0" src="../../db/d45/qr__decomposition_8c__incl.svg" width="354" height="202"><p><b>This browser is not able to show SVG: try Firefox, Chrome, Safari, or Opera instead.</b></p></iframe>
</div>
</div>
</div><table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="func-members"></a>
Functions</h2></td></tr>
<tr class="memitem:a840291bc02cba5474a4cb46a9b9566fe"><td class="memItemLeft" align="right" valign="top">int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../d5/d23/qr__decomposition_8c.html#a840291bc02cba5474a4cb46a9b9566fe">main</a> (void)</td></tr>
<tr class="separator:a840291bc02cba5474a4cb46a9b9566fe"><td class="memSeparator" colspan="2">&#160;</td></tr>
</table>
<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><p>Program to compute the <a href="https://en.wikipedia.org/wiki/QR_decomposition">QR decomposition</a> of a given matrix. </p>
<dl class="section author"><dt>Author</dt><dd><a href="https://github.com/kvedala">Krishna Vedala</a> </dd></dl>
</div><h2 class="groupheader">Function Documentation</h2>
<a id="a840291bc02cba5474a4cb46a9b9566fe"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a840291bc02cba5474a4cb46a9b9566fe">&#9670;&nbsp;</a></span>main()</h2>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int main </td>
<td>(</td>
<td class="paramtype">void&#160;</td>
<td class="paramname"></td><td>)</td>
<td></td>
</tr>
</table>
</div><div class="memdoc">
<p>main function </p>
<div class="fragment"><div class="line"><a name="l00019"></a><span class="lineno"> 19</span>&#160;{</div>
<div class="line"><a name="l00020"></a><span class="lineno"> 20</span>&#160; <span class="keywordtype">double</span> **A;</div>
<div class="line"><a name="l00021"></a><span class="lineno"> 21</span>&#160; <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> ROWS, COLUMNS;</div>
<div class="line"><a name="l00022"></a><span class="lineno"> 22</span>&#160; </div>
<div class="line"><a name="l00023"></a><span class="lineno"> 23</span>&#160; printf(<span class="stringliteral">&quot;Enter the number of rows and columns: &quot;</span>);</div>
<div class="line"><a name="l00024"></a><span class="lineno"> 24</span>&#160; scanf(<span class="stringliteral">&quot;%u %u&quot;</span>, &amp;ROWS, &amp;COLUMNS);</div>
<div class="line"><a name="l00025"></a><span class="lineno"> 25</span>&#160; <span class="keywordflow">if</span> (ROWS &lt; COLUMNS)</div>
<div class="line"><a name="l00026"></a><span class="lineno"> 26</span>&#160; {</div>
<div class="line"><a name="l00027"></a><span class="lineno"> 27</span>&#160; fprintf(stderr,</div>
<div class="line"><a name="l00028"></a><span class="lineno"> 28</span>&#160; <span class="stringliteral">&quot;Number of rows must be greater than or equal to &quot;</span></div>
<div class="line"><a name="l00029"></a><span class="lineno"> 29</span>&#160; <span class="stringliteral">&quot;number of columns.\n&quot;</span>);</div>
<div class="line"><a name="l00030"></a><span class="lineno"> 30</span>&#160; <span class="keywordflow">return</span> -1;</div>
<div class="line"><a name="l00031"></a><span class="lineno"> 31</span>&#160; }</div>
<div class="line"><a name="l00032"></a><span class="lineno"> 32</span>&#160; </div>
<div class="line"><a name="l00033"></a><span class="lineno"> 33</span>&#160; printf(<span class="stringliteral">&quot;Enter matrix elements row-wise:\n&quot;</span>);</div>
<div class="line"><a name="l00034"></a><span class="lineno"> 34</span>&#160; </div>
<div class="line"><a name="l00035"></a><span class="lineno"> 35</span>&#160; A = (<span class="keywordtype">double</span> **)malloc(ROWS * <span class="keyword">sizeof</span>(<span class="keywordtype">double</span> *));</div>
<div class="line"><a name="l00036"></a><span class="lineno"> 36</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i &lt; ROWS; i++)</div>
<div class="line"><a name="l00037"></a><span class="lineno"> 37</span>&#160; A[i] = (<span class="keywordtype">double</span> *)malloc(COLUMNS * <span class="keyword">sizeof</span>(<span class="keywordtype">double</span>));</div>
<div class="line"><a name="l00038"></a><span class="lineno"> 38</span>&#160; </div>
<div class="line"><a name="l00039"></a><span class="lineno"> 39</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i &lt; ROWS; i++)</div>
<div class="line"><a name="l00040"></a><span class="lineno"> 40</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> j = 0; j &lt; COLUMNS; j++) scanf(<span class="stringliteral">&quot;%lf&quot;</span>, &amp;A[i][j]);</div>
<div class="line"><a name="l00041"></a><span class="lineno"> 41</span>&#160; </div>
<div class="line"><a name="l00042"></a><span class="lineno"> 42</span>&#160; <a class="code" href="../../d4/d68/qr__decompose_8h.html#a90562ce8c3707401e9c5809dece68d6a">print_matrix</a>(A, ROWS, COLUMNS);</div>
<div class="line"><a name="l00043"></a><span class="lineno"> 43</span>&#160; </div>
<div class="line"><a name="l00044"></a><span class="lineno"> 44</span>&#160; <span class="keywordtype">double</span> **R = (<span class="keywordtype">double</span> **)malloc(<span class="keyword">sizeof</span>(<span class="keywordtype">double</span> *) * ROWS);</div>
<div class="line"><a name="l00045"></a><span class="lineno"> 45</span>&#160; <span class="keywordtype">double</span> **Q = (<span class="keywordtype">double</span> **)malloc(<span class="keyword">sizeof</span>(<span class="keywordtype">double</span> *) * ROWS);</div>
<div class="line"><a name="l00046"></a><span class="lineno"> 46</span>&#160; <span class="keywordflow">if</span> (!Q || !R)</div>
<div class="line"><a name="l00047"></a><span class="lineno"> 47</span>&#160; {</div>
<div class="line"><a name="l00048"></a><span class="lineno"> 48</span>&#160; perror(<span class="stringliteral">&quot;Unable to allocate memory for Q &amp; R!&quot;</span>);</div>
<div class="line"><a name="l00049"></a><span class="lineno"> 49</span>&#160; <span class="keywordflow">return</span> -1;</div>
<div class="line"><a name="l00050"></a><span class="lineno"> 50</span>&#160; }</div>
<div class="line"><a name="l00051"></a><span class="lineno"> 51</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i &lt; ROWS; i++)</div>
<div class="line"><a name="l00052"></a><span class="lineno"> 52</span>&#160; {</div>
<div class="line"><a name="l00053"></a><span class="lineno"> 53</span>&#160; R[i] = (<span class="keywordtype">double</span> *)malloc(<span class="keyword">sizeof</span>(<span class="keywordtype">double</span>) * COLUMNS);</div>
<div class="line"><a name="l00054"></a><span class="lineno"> 54</span>&#160; Q[i] = (<span class="keywordtype">double</span> *)malloc(<span class="keyword">sizeof</span>(<span class="keywordtype">double</span>) * ROWS);</div>
<div class="line"><a name="l00055"></a><span class="lineno"> 55</span>&#160; <span class="keywordflow">if</span> (!Q[i] || !R[i])</div>
<div class="line"><a name="l00056"></a><span class="lineno"> 56</span>&#160; {</div>
<div class="line"><a name="l00057"></a><span class="lineno"> 57</span>&#160; perror(<span class="stringliteral">&quot;Unable to allocate memory for Q &amp; R.&quot;</span>);</div>
<div class="line"><a name="l00058"></a><span class="lineno"> 58</span>&#160; <span class="keywordflow">return</span> -1;</div>
<div class="line"><a name="l00059"></a><span class="lineno"> 59</span>&#160; }</div>
<div class="line"><a name="l00060"></a><span class="lineno"> 60</span>&#160; }</div>
<div class="line"><a name="l00061"></a><span class="lineno"> 61</span>&#160; </div>
<div class="line"><a name="l00062"></a><span class="lineno"> 62</span>&#160; clock_t t1 = clock();</div>
<div class="line"><a name="l00063"></a><span class="lineno"> 63</span>&#160; <a class="code" href="../../d4/d68/qr__decompose_8h.html#a45c7640d9d22c89c11beb1f567843c56">qr_decompose</a>(A, Q, R, ROWS, COLUMNS);</div>
<div class="line"><a name="l00064"></a><span class="lineno"> 64</span>&#160; <span class="keywordtype">double</span> dtime = (double)(clock() - t1) / CLOCKS_PER_SEC;</div>
<div class="line"><a name="l00065"></a><span class="lineno"> 65</span>&#160; </div>
<div class="line"><a name="l00066"></a><span class="lineno"> 66</span>&#160; <a class="code" href="../../d4/d68/qr__decompose_8h.html#a90562ce8c3707401e9c5809dece68d6a">print_matrix</a>(R, ROWS, COLUMNS);</div>
<div class="line"><a name="l00067"></a><span class="lineno"> 67</span>&#160; <a class="code" href="../../d4/d68/qr__decompose_8h.html#a90562ce8c3707401e9c5809dece68d6a">print_matrix</a>(Q, ROWS, COLUMNS);</div>
<div class="line"><a name="l00068"></a><span class="lineno"> 68</span>&#160; printf(<span class="stringliteral">&quot;Time taken to compute: %.4g sec\n&quot;</span>, dtime);</div>
<div class="line"><a name="l00069"></a><span class="lineno"> 69</span>&#160; </div>
<div class="line"><a name="l00070"></a><span class="lineno"> 70</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i &lt; ROWS; i++)</div>
<div class="line"><a name="l00071"></a><span class="lineno"> 71</span>&#160; {</div>
<div class="line"><a name="l00072"></a><span class="lineno"> 72</span>&#160; free(A[i]);</div>
<div class="line"><a name="l00073"></a><span class="lineno"> 73</span>&#160; free(R[i]);</div>
<div class="line"><a name="l00074"></a><span class="lineno"> 74</span>&#160; free(Q[i]);</div>
<div class="line"><a name="l00075"></a><span class="lineno"> 75</span>&#160; }</div>
<div class="line"><a name="l00076"></a><span class="lineno"> 76</span>&#160; free(A);</div>
<div class="line"><a name="l00077"></a><span class="lineno"> 77</span>&#160; free(R);</div>
<div class="line"><a name="l00078"></a><span class="lineno"> 78</span>&#160; free(Q);</div>
<div class="line"><a name="l00079"></a><span class="lineno"> 79</span>&#160; <span class="keywordflow">return</span> 0;</div>
<div class="line"><a name="l00080"></a><span class="lineno"> 80</span>&#160;}</div>
</div><!-- fragment --><div class="dynheader">
Here is the call graph for this function:</div>
<div class="dyncontent">
<div class="center"><iframe scrolling="no" frameborder="0" src="../../d5/d23/qr__decomposition_8c_a840291bc02cba5474a4cb46a9b9566fe_cgraph.svg" width="486" height="164"><p><b>This browser is not able to show SVG: try Firefox, Chrome, Safari, or Opera instead.</b></p></iframe>
</div>
</div>
</div>
</div>
</div><!-- contents -->
</div><!-- doc-content -->
<div class="ttc" id="aqr__decompose_8h_html_a45c7640d9d22c89c11beb1f567843c56"><div class="ttname"><a href="../../d4/d68/qr__decompose_8h.html#a45c7640d9d22c89c11beb1f567843c56">qr_decompose</a></div><div class="ttdeci">void qr_decompose(double **A, double **Q, double **R, int M, int N)</div><div class="ttdef"><b>Definition:</b> qr_decompose.h:142</div></div>
<div class="ttc" id="aqr__decompose_8h_html_a90562ce8c3707401e9c5809dece68d6a"><div class="ttname"><a href="../../d4/d68/qr__decompose_8h.html#a90562ce8c3707401e9c5809dece68d6a">print_matrix</a></div><div class="ttdeci">void print_matrix(double **A, int M, int N)</div><div class="ttdef"><b>Definition:</b> qr_decompose.h:22</div></div>
<!-- start footer part -->
<div id="nav-path" class="navpath"><!-- id is needed for treeview function! -->
<ul>
<li class="navelem"><a class="el" href="../../dir_9c6faab82c22511b50177aa2e38e2780.html">numerical_methods</a></li><li class="navelem"><a class="el" href="../../d5/d23/qr__decomposition_8c.html">qr_decomposition.c</a></li>
<li class="footer">Generated by
<a href="http://www.doxygen.org/index.html">
<img class="footer" src="../../doxygen.png" alt="doxygen"/></a> 1.8.18 </li>
</ul>
</div>
</body>
</html>