Home Explore Help
Sign In
cpp
/
JoltPhysics
mirror of https://github.com/jrouwe/JoltPhysics.git
2
0
Fork 0
Files Issues 0 Wiki
Branch: gh-pages
Branches Tags
JoltPhysics
/
_eigen_value_symmetric_8h_source.html

_eigen_value_symmetric_8h_source.html 37 KB
Permalink History Raw

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302 
  1. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "https://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
    2. 

  2. <html xmlns="http://www.w3.org/1999/xhtml" lang="en-US">
    3. 

  3. <head>
    4. 

  4. <meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
    5. 

  5. <meta http-equiv="X-UA-Compatible" content="IE=11"/>
    6. 

  6. <meta name="generator" content="Doxygen 1.12.0"/>
    7. 

  7. <meta name="viewport" content="width=device-width, initial-scale=1"/>
    8. 

  8. <title>Jolt Physics: Jolt/Math/EigenValueSymmetric.h Source File</title>
    9. 

  9. <link href="tabs.css" rel="stylesheet" type="text/css"/>
    10. 

  10. <script type="text/javascript" src="jquery.js"></script>
    11. 

  11. <script type="text/javascript" src="dynsections.js"></script>
    12. 

  12. <script type="text/javascript" src="clipboard.js"></script>
    13. 

  13. <link href="navtree.css" rel="stylesheet" type="text/css"/>
    14. 

  14. <script type="text/javascript" src="navtreedata.js"></script>
    15. 

  15. <script type="text/javascript" src="navtree.js"></script>
    16. 

  16. <script type="text/javascript" src="resize.js"></script>
    17. 

  17. <script type="text/javascript" src="cookie.js"></script>
    18. 

  18. <link href="search/search.css" rel="stylesheet" type="text/css"/>
    19. 

  19. <script type="text/javascript" src="search/searchdata.js"></script>
    20. 

  20. <script type="text/javascript" src="search/search.js"></script>
    21. 

  21. <script type="text/x-mathjax-config">
    22. 

  22. MathJax.Hub.Config({
    23. 

  23.   extensions: ["tex2jax.js"],
    24. 

  24.   jax: ["input/TeX","output/HTML-CSS"],
    25. 

  25. });
    26. 

  26. </script>
    27. 

  27. <script type="text/javascript" async="async" src="https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.5/MathJax.js"></script>
    28. 

  28. <link href="doxygen.css" rel="stylesheet" type="text/css" />
    29. 

  29. </head>
    30. 

  30. <body>
    31. 

  31. <div id="top"><!-- do not remove this div, it is closed by doxygen! -->
    32. 

  32. <div id="titlearea">
    33. 

  33. <table cellspacing="0" cellpadding="0">
    34. 

  34.  <tbody>
    35. 

  35.  <tr id="projectrow">
    36. 

  36.   <td id="projectlogo"><img alt="Logo" src="LogoSmall.png"/></td>
    37. 

  37.   <td id="projectalign">
    38. 

  38.    <div id="projectname">Jolt Physics
    39. 

  39.    </div>
    40. 

  40.    <div id="projectbrief">A multi core friendly Game Physics Engine</div>
    41. 

  41.   </td>
    42. 

  42.  </tr>
    43. 

  43.  </tbody>
    44. 

  44. </table>
    45. 

  45. </div>
    46. 

  46. <!-- end header part -->
    47. 

  47. <!-- Generated by Doxygen 1.12.0 -->
    48. 

  48. <script type="text/javascript">
    49. 

  49. /* @license magnet:?xt=urn:btih:d3d9a9a6595521f9666a5e94cc830dab83b65699&amp;dn=expat.txt MIT */
    50. 

  50. var searchBox = new SearchBox("searchBox", "search/",'.html');
    51. 

  51. /* @license-end */
    52. 

  52. </script>
    53. 

  53. <script type="text/javascript">
    54. 

  54. /* @license magnet:?xt=urn:btih:d3d9a9a6595521f9666a5e94cc830dab83b65699&amp;dn=expat.txt MIT */
    55. 

  55. $(function() { codefold.init(0); });
    56. 

  56. /* @license-end */
    57. 

  57. </script>
    58. 

  58. <script type="text/javascript" src="menudata.js"></script>
    59. 

  59. <script type="text/javascript" src="menu.js"></script>
    60. 

  60. <script type="text/javascript">
    61. 

  61. /* @license magnet:?xt=urn:btih:d3d9a9a6595521f9666a5e94cc830dab83b65699&amp;dn=expat.txt MIT */
    62. 

  62. $(function() {
    63. 

  63.   initMenu('',true,false,'search.php','Search',true);
    64. 

  64.   $(function() { init_search(); });
    65. 

  65. });
    66. 

  66. /* @license-end */
    67. 

  67. </script>
    68. 

  68. <div id="main-nav"></div>
    69. 

  69. </div><!-- top -->
    70. 

  70. <div id="side-nav" class="ui-resizable side-nav-resizable">
    71. 

  71.   <div id="nav-tree">
    72. 

  72.     <div id="nav-tree-contents">
    73. 

  73.       <div id="nav-sync" class="sync"></div>
    74. 

  74.     </div>
    75. 

  75.   </div>
    76. 

  76.   <div id="splitbar" style="-moz-user-select:none;" 
    77. 

  77.        class="ui-resizable-handle">
    78. 

  78.   </div>
    79. 

  79. </div>
    80. 

  80. <script type="text/javascript">
    81. 

  81. /* @license magnet:?xt=urn:btih:d3d9a9a6595521f9666a5e94cc830dab83b65699&amp;dn=expat.txt MIT */
    82. 

  82. $(function(){initNavTree('_eigen_value_symmetric_8h_source.html',''); initResizable(true); });
    83. 

  83. /* @license-end */
    84. 

  84. </script>
    85. 

  85. <div id="doc-content">
    86. 

  86. <!-- window showing the filter options -->
    87. 

  87. <div id="MSearchSelectWindow"
    88. 

  88.      onmouseover="return searchBox.OnSearchSelectShow()"
    89. 

  89.      onmouseout="return searchBox.OnSearchSelectHide()"
    90. 

  90.      onkeydown="return searchBox.OnSearchSelectKey(event)">
    91. 

  91. </div>
    92. 

  92. 

  93. <!-- iframe showing the search results (closed by default) -->
    94. 

  94. <div id="MSearchResultsWindow">
    95. 

  95. <div id="MSearchResults">
    96. 

  96. <div class="SRPage">
    97. 

  97. <div id="SRIndex">
    98. 

  98. <div id="SRResults"></div>
    99. 

  99. <div class="SRStatus" id="Loading">Loading...</div>
    100. 

  100. <div class="SRStatus" id="Searching">Searching...</div>
    101. 

  101. <div class="SRStatus" id="NoMatches">No Matches</div>
    102. 

  102. </div>
    103. 

  103. </div>
    104. 

  104. </div>
    105. 

  105. </div>
    106. 

  106. 

  107. <div class="header">
    108. 

  108.   <div class="headertitle"><div class="title">EigenValueSymmetric.h</div></div>
    109. 

  109. </div><!--header-->
    110. 

  110. <div class="contents">
    111. 

  111. <a href="_eigen_value_symmetric_8h.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a id="l00001" name="l00001"></a><span class="lineno">    1</span><span class="comment">// Jolt Physics Library (https://github.com/jrouwe/JoltPhysics)</span></div>
    112. 

  112. <div class="line"><a id="l00002" name="l00002"></a><span class="lineno">    2</span><span class="comment">// SPDX-FileCopyrightText: 2021 Jorrit Rouwe</span></div>
    113. 

  113. <div class="line"><a id="l00003" name="l00003"></a><span class="lineno">    3</span><span class="comment">// SPDX-License-Identifier: MIT</span></div>
    114. 

  114. <div class="line"><a id="l00004" name="l00004"></a><span class="lineno">    4</span> </div>
    115. 

  115. <div class="line"><a id="l00005" name="l00005"></a><span class="lineno">    5</span><span class="preprocessor">#pragma once</span></div>
    116. 

  116. <div class="line"><a id="l00006" name="l00006"></a><span class="lineno">    6</span> </div>
    117. 

  117. <div class="line"><a id="l00007" name="l00007"></a><span class="lineno">    7</span><span class="preprocessor">#include &lt;<a class="code" href="_f_p_exception_8h.html">Jolt/Core/FPException.h</a>&gt;</span></div>
    118. 

  118. <div class="line"><a id="l00008" name="l00008"></a><span class="lineno">    8</span> </div>
    119. 

  119. <div class="line"><a id="l00009" name="l00009"></a><span class="lineno">    9</span><a class="code hl_define" href="_core_8h.html#ad14098b68b8c44ea6112601031268405">JPH_NAMESPACE_BEGIN</a></div>
    120. 

  120. <div class="line"><a id="l00010" name="l00010"></a><span class="lineno">   10</span> </div>
    121. 

  121. <div class="line"><a id="l00028" name="l00028"></a><span class="lineno">   28</span><span class="keyword">template</span> &lt;<span class="keyword">class</span> Vector, <span class="keyword">class</span> Matrix&gt;</div>
    122. 

  122. <div class="foldopen" id="foldopen00029" data-start="{" data-end="}">
    123. 

  123. <div class="line"><a id="l00029" name="l00029"></a><span class="lineno"><a class="line" href="_eigen_value_symmetric_8h.html#a63488e363acda8a1bd4cd3d297bf4d54">   29</a></span><span class="keywordtype">bool</span> <a class="code hl_function" href="_eigen_value_symmetric_8h.html#a63488e363acda8a1bd4cd3d297bf4d54">EigenValueSymmetric</a>(<span class="keyword">const</span> <a class="code hl_class" href="class_matrix.html">Matrix</a> &amp;inMatrix, <a class="code hl_class" href="class_matrix.html">Matrix</a> &amp;outEigVec, <a class="code hl_class" href="class_vector.html">Vector</a> &amp;outEigVal)</div>
    124. 

  124. <div class="line"><a id="l00030" name="l00030"></a><span class="lineno">   30</span>{</div>
    125. 

  125. <div class="line"><a id="l00031" name="l00031"></a><span class="lineno">   31</span>    <span class="comment">// This algorithm can generate infinite values, see comment below</span></div>
    126. 

  126. <div class="line"><a id="l00032" name="l00032"></a><span class="lineno">   32</span>    <a class="code hl_class" href="class_f_p_exception_disable_invalid.html">FPExceptionDisableInvalid</a> disable_invalid;</div>
    127. 

  127. <div class="line"><a id="l00033" name="l00033"></a><span class="lineno">   33</span>    <a class="code hl_define" href="_core_8h.html#a719a73b9e445920bf5969f05d01ce69c">JPH_UNUSED</a>(disable_invalid);</div>
    128. 

  128. <div class="line"><a id="l00034" name="l00034"></a><span class="lineno">   34</span> </div>
    129. 

  129. <div class="line"><a id="l00035" name="l00035"></a><span class="lineno">   35</span>    <span class="comment">// Maximum number of sweeps to make</span></div>
    130. 

  130. <div class="line"><a id="l00036" name="l00036"></a><span class="lineno">   36</span>    <span class="keyword">const</span> <span class="keywordtype">int</span> cMaxSweeps = 50;</div>
    131. 

  131. <div class="line"><a id="l00037" name="l00037"></a><span class="lineno">   37</span> </div>
    132. 

  132. <div class="line"><a id="l00038" name="l00038"></a><span class="lineno">   38</span>    <span class="comment">// Get problem dimension</span></div>
    133. 

  133. <div class="line"><a id="l00039" name="l00039"></a><span class="lineno">   39</span>    <span class="keyword">const</span> <a class="code hl_typedef" href="_core_8h.html#a69aa29b598b851b0640aa225a9e5d61d">uint</a> n = inMatrix.<a class="code hl_function" href="class_matrix.html#a295baf4af956351b6bf05548e16887ee">GetRows</a>();</div>
    134. 

  134. <div class="line"><a id="l00040" name="l00040"></a><span class="lineno">   40</span> </div>
    135. 

  135. <div class="line"><a id="l00041" name="l00041"></a><span class="lineno">   41</span>    <span class="comment">// Make sure the dimensions are right</span></div>
    136. 

  136. <div class="line"><a id="l00042" name="l00042"></a><span class="lineno">   42</span>    <a class="code hl_define" href="_issue_reporting_8h.html#aaf6b1df827e11b7ca5f6f8778bd8f8cd">JPH_ASSERT</a>(inMatrix.<a class="code hl_function" href="class_matrix.html#a295baf4af956351b6bf05548e16887ee">GetRows</a>() == n);</div>
    137. 

  137. <div class="line"><a id="l00043" name="l00043"></a><span class="lineno">   43</span>    <a class="code hl_define" href="_issue_reporting_8h.html#aaf6b1df827e11b7ca5f6f8778bd8f8cd">JPH_ASSERT</a>(inMatrix.<a class="code hl_function" href="class_matrix.html#a45bd49a18dec51ca82c58aa5d12572be">GetCols</a>() == n);</div>
    138. 

  138. <div class="line"><a id="l00044" name="l00044"></a><span class="lineno">   44</span>    <a class="code hl_define" href="_issue_reporting_8h.html#aaf6b1df827e11b7ca5f6f8778bd8f8cd">JPH_ASSERT</a>(outEigVec.<a class="code hl_function" href="class_matrix.html#a295baf4af956351b6bf05548e16887ee">GetRows</a>() == n);</div>
    139. 

  139. <div class="line"><a id="l00045" name="l00045"></a><span class="lineno">   45</span>    <a class="code hl_define" href="_issue_reporting_8h.html#aaf6b1df827e11b7ca5f6f8778bd8f8cd">JPH_ASSERT</a>(outEigVec.<a class="code hl_function" href="class_matrix.html#a45bd49a18dec51ca82c58aa5d12572be">GetCols</a>() == n);</div>
    140. 

  140. <div class="line"><a id="l00046" name="l00046"></a><span class="lineno">   46</span>    <a class="code hl_define" href="_issue_reporting_8h.html#aaf6b1df827e11b7ca5f6f8778bd8f8cd">JPH_ASSERT</a>(outEigVal.<a class="code hl_function" href="class_vector.html#a8c1387fdaa60b9569f5e9acb1363b7fb">GetRows</a>() == n);</div>
    141. 

  141. <div class="line"><a id="l00047" name="l00047"></a><span class="lineno">   47</span>    <a class="code hl_define" href="_issue_reporting_8h.html#aaf6b1df827e11b7ca5f6f8778bd8f8cd">JPH_ASSERT</a>(outEigVec.<a class="code hl_function" href="class_matrix.html#a35353d8c2a5a249e5368e654bca5fc79">IsIdentity</a>());</div>
    142. 

  142. <div class="line"><a id="l00048" name="l00048"></a><span class="lineno">   48</span> </div>
    143. 

  143. <div class="line"><a id="l00049" name="l00049"></a><span class="lineno">   49</span>    <span class="comment">// Get the matrix in a so we can mess with it</span></div>
    144. 

  144. <div class="line"><a id="l00050" name="l00050"></a><span class="lineno">   50</span>    <a class="code hl_class" href="class_matrix.html">Matrix</a> a = inMatrix;</div>
    145. 

  145. <div class="line"><a id="l00051" name="l00051"></a><span class="lineno">   51</span> </div>
    146. 

  146. <div class="line"><a id="l00052" name="l00052"></a><span class="lineno">   52</span>    <a class="code hl_class" href="class_vector.html">Vector</a> b, z;</div>
    147. 

  147. <div class="line"><a id="l00053" name="l00053"></a><span class="lineno">   53</span> </div>
    148. 

  148. <div class="line"><a id="l00054" name="l00054"></a><span class="lineno">   54</span>    <span class="keywordflow">for</span> (<a class="code hl_typedef" href="_core_8h.html#a69aa29b598b851b0640aa225a9e5d61d">uint</a> ip = 0; ip &lt; n; ++ip)</div>
    149. 

  149. <div class="line"><a id="l00055" name="l00055"></a><span class="lineno">   55</span>    {</div>
    150. 

  150. <div class="line"><a id="l00056" name="l00056"></a><span class="lineno">   56</span>        <span class="comment">// Initialize b to diagonal of a</span></div>
    151. 

  151. <div class="line"><a id="l00057" name="l00057"></a><span class="lineno">   57</span>        b[ip] = a(ip, ip);</div>
    152. 

  152. <div class="line"><a id="l00058" name="l00058"></a><span class="lineno">   58</span> </div>
    153. 

  153. <div class="line"><a id="l00059" name="l00059"></a><span class="lineno">   59</span>        <span class="comment">// Initialize output to diagonal of a</span></div>
    154. 

  154. <div class="line"><a id="l00060" name="l00060"></a><span class="lineno">   60</span>        outEigVal[ip] = a(ip, ip);</div>
    155. 

  155. <div class="line"><a id="l00061" name="l00061"></a><span class="lineno">   61</span> </div>
    156. 

  156. <div class="line"><a id="l00062" name="l00062"></a><span class="lineno">   62</span>        <span class="comment">// Reset z</span></div>
    157. 

  157. <div class="line"><a id="l00063" name="l00063"></a><span class="lineno">   63</span>        z[ip] = 0.0f;</div>
    158. 

  158. <div class="line"><a id="l00064" name="l00064"></a><span class="lineno">   64</span>    }</div>
    159. 

  159. <div class="line"><a id="l00065" name="l00065"></a><span class="lineno">   65</span> </div>
    160. 

  160. <div class="line"><a id="l00066" name="l00066"></a><span class="lineno">   66</span>    <span class="keywordflow">for</span> (<span class="keywordtype">int</span> sweep = 0; sweep &lt; cMaxSweeps; ++sweep)</div>
    161. 

  161. <div class="line"><a id="l00067" name="l00067"></a><span class="lineno">   67</span>    {</div>
    162. 

  162. <div class="line"><a id="l00068" name="l00068"></a><span class="lineno">   68</span>        <span class="comment">// Get the sum of the off-diagonal elements of a</span></div>
    163. 

  163. <div class="line"><a id="l00069" name="l00069"></a><span class="lineno">   69</span>        <span class="keywordtype">float</span> sm = 0.0f;</div>
    164. 

  164. <div class="line"><a id="l00070" name="l00070"></a><span class="lineno">   70</span>        <span class="keywordflow">for</span> (<a class="code hl_typedef" href="_core_8h.html#a69aa29b598b851b0640aa225a9e5d61d">uint</a> ip = 0; ip &lt; n - 1; ++ip)</div>
    165. 

  165. <div class="line"><a id="l00071" name="l00071"></a><span class="lineno">   71</span>            <span class="keywordflow">for</span> (<a class="code hl_typedef" href="_core_8h.html#a69aa29b598b851b0640aa225a9e5d61d">uint</a> iq = ip + 1; iq &lt; n; ++iq)</div>
    166. 

  166. <div class="line"><a id="l00072" name="l00072"></a><span class="lineno">   72</span>                sm += abs(a(ip, iq));</div>
    167. 

  167. <div class="line"><a id="l00073" name="l00073"></a><span class="lineno">   73</span>        <span class="keywordtype">float</span> avg_sm = sm / <a class="code hl_function" href="_math_8h.html#a61379b8b743a16fe823daeebc1482570">Square</a>(n);</div>
    168. 

  168. <div class="line"><a id="l00074" name="l00074"></a><span class="lineno">   74</span> </div>
    169. 

  169. <div class="line"><a id="l00075" name="l00075"></a><span class="lineno">   75</span>        <span class="comment">// Normal return, convergence to machine underflow</span></div>
    170. 

  170. <div class="line"><a id="l00076" name="l00076"></a><span class="lineno">   76</span>        <span class="keywordflow">if</span> (avg_sm &lt; FLT_MIN) <span class="comment">// Original code: sm == 0.0f, when the average is denormal, we also consider it machine underflow</span></div>
    171. 

  171. <div class="line"><a id="l00077" name="l00077"></a><span class="lineno">   77</span>        {</div>
    172. 

  172. <div class="line"><a id="l00078" name="l00078"></a><span class="lineno">   78</span>            <span class="comment">// Sanity checks</span></div>
    173. 

  173. <div class="line"><a id="l00079" name="l00079"></a><span class="lineno">   79</span><span class="preprocessor">            #ifdef JPH_ENABLE_ASSERTS</span></div>
    174. 

  174. <div class="line"><a id="l00080" name="l00080"></a><span class="lineno">   80</span>                <span class="keywordflow">for</span> (<a class="code hl_typedef" href="_core_8h.html#a69aa29b598b851b0640aa225a9e5d61d">uint</a> c = 0; c &lt; n; ++c)</div>
    175. 

  175. <div class="line"><a id="l00081" name="l00081"></a><span class="lineno">   81</span>                {</div>
    176. 

  176. <div class="line"><a id="l00082" name="l00082"></a><span class="lineno">   82</span>                    <span class="comment">// Check if the eigenvector is normalized</span></div>
    177. 

  177. <div class="line"><a id="l00083" name="l00083"></a><span class="lineno">   83</span>                    <a class="code hl_define" href="_issue_reporting_8h.html#aaf6b1df827e11b7ca5f6f8778bd8f8cd">JPH_ASSERT</a>(outEigVec.<a class="code hl_function" href="class_matrix.html#a92a370676cc7e0788bc217a358170b4a">GetColumn</a>(c).IsNormalized());</div>
    178. 

  178. <div class="line"><a id="l00084" name="l00084"></a><span class="lineno">   84</span> </div>
    179. 

  179. <div class="line"><a id="l00085" name="l00085"></a><span class="lineno">   85</span>                    <span class="comment">// Check if inMatrix * eigen_vector = eigen_value * eigen_vector</span></div>
    180. 

  180. <div class="line"><a id="l00086" name="l00086"></a><span class="lineno">   86</span>                    <a class="code hl_class" href="class_vector.html">Vector</a> mat_eigvec = inMatrix * outEigVec.<a class="code hl_function" href="class_matrix.html#a92a370676cc7e0788bc217a358170b4a">GetColumn</a>(c);</div>
    181. 

  181. <div class="line"><a id="l00087" name="l00087"></a><span class="lineno">   87</span>                    <a class="code hl_class" href="class_vector.html">Vector</a> eigval_eigvec = outEigVal[c] * outEigVec.<a class="code hl_function" href="class_matrix.html#a92a370676cc7e0788bc217a358170b4a">GetColumn</a>(c);</div>
    182. 

  182. <div class="line"><a id="l00088" name="l00088"></a><span class="lineno">   88</span>                    <a class="code hl_define" href="_issue_reporting_8h.html#aaf6b1df827e11b7ca5f6f8778bd8f8cd">JPH_ASSERT</a>(mat_eigvec.<a class="code hl_function" href="class_vector.html#a5e282c7195754fe9b4864ba772e3cad9">IsClose</a>(eigval_eigvec, max(mat_eigvec.<a class="code hl_function" href="class_vector.html#afa80dcde530acc7b7911526d921b60e8">LengthSq</a>(), eigval_eigvec.<a class="code hl_function" href="class_vector.html#afa80dcde530acc7b7911526d921b60e8">LengthSq</a>()) * 1.0e-6f));</div>
    183. 

  183. <div class="line"><a id="l00089" name="l00089"></a><span class="lineno">   89</span>                }</div>
    184. 

  184. <div class="line"><a id="l00090" name="l00090"></a><span class="lineno">   90</span><span class="preprocessor">            #endif</span></div>
    185. 

  185. <div class="line"><a id="l00091" name="l00091"></a><span class="lineno">   91</span> </div>
    186. 

  186. <div class="line"><a id="l00092" name="l00092"></a><span class="lineno">   92</span>            <span class="comment">// Success</span></div>
    187. 

  187. <div class="line"><a id="l00093" name="l00093"></a><span class="lineno">   93</span>            <span class="keywordflow">return</span> <span class="keyword">true</span>;</div>
    188. 

  188. <div class="line"><a id="l00094" name="l00094"></a><span class="lineno">   94</span>        }</div>
    189. 

  189. <div class="line"><a id="l00095" name="l00095"></a><span class="lineno">   95</span> </div>
    190. 

  190. <div class="line"><a id="l00096" name="l00096"></a><span class="lineno">   96</span>        <span class="comment">// On the first three sweeps use a fraction of the sum of the off diagonal elements as threshold</span></div>
    191. 

  191. <div class="line"><a id="l00097" name="l00097"></a><span class="lineno">   97</span>        <span class="comment">// Note that we pick a minimum threshold of FLT_MIN because dividing by a denormalized number is likely to result in infinity.</span></div>
    192. 

  192. <div class="line"><a id="l00098" name="l00098"></a><span class="lineno">   98</span>        <span class="keywordtype">float</span> thresh = sweep &lt; 4? 0.2f * avg_sm : FLT_MIN; <span class="comment">// Original code: 0.0f instead of FLT_MIN</span></div>
    193. 

  193. <div class="line"><a id="l00099" name="l00099"></a><span class="lineno">   99</span> </div>
    194. 

  194. <div class="line"><a id="l00100" name="l00100"></a><span class="lineno">  100</span>        <span class="keywordflow">for</span> (<a class="code hl_typedef" href="_core_8h.html#a69aa29b598b851b0640aa225a9e5d61d">uint</a> ip = 0; ip &lt; n - 1; ++ip)</div>
    195. 

  195. <div class="line"><a id="l00101" name="l00101"></a><span class="lineno">  101</span>            <span class="keywordflow">for</span> (<a class="code hl_typedef" href="_core_8h.html#a69aa29b598b851b0640aa225a9e5d61d">uint</a> iq = ip + 1; iq &lt; n; ++iq)</div>
    196. 

  196. <div class="line"><a id="l00102" name="l00102"></a><span class="lineno">  102</span>            {</div>
    197. 

  197. <div class="line"><a id="l00103" name="l00103"></a><span class="lineno">  103</span>                <span class="keywordtype">float</span> &amp;a_pq = a(ip, iq);</div>
    198. 

  198. <div class="line"><a id="l00104" name="l00104"></a><span class="lineno">  104</span>                <span class="keywordtype">float</span> &amp;eigval_p = outEigVal[ip];</div>
    199. 

  199. <div class="line"><a id="l00105" name="l00105"></a><span class="lineno">  105</span>                <span class="keywordtype">float</span> &amp;eigval_q = outEigVal[iq];</div>
    200. 

  200. <div class="line"><a id="l00106" name="l00106"></a><span class="lineno">  106</span> </div>
    201. 

  201. <div class="line"><a id="l00107" name="l00107"></a><span class="lineno">  107</span>                <span class="keywordtype">float</span> abs_a_pq = abs(a_pq);</div>
    202. 

  202. <div class="line"><a id="l00108" name="l00108"></a><span class="lineno">  108</span>                <span class="keywordtype">float</span> g = 100.0f * abs_a_pq;</div>
    203. 

  203. <div class="line"><a id="l00109" name="l00109"></a><span class="lineno">  109</span> </div>
    204. 

  204. <div class="line"><a id="l00110" name="l00110"></a><span class="lineno">  110</span>                <span class="comment">// After four sweeps, skip the rotation if the off-diagonal element is small</span></div>
    205. 

  205. <div class="line"><a id="l00111" name="l00111"></a><span class="lineno">  111</span>                <span class="keywordflow">if</span> (sweep &gt; 4</div>
    206. 

  206. <div class="line"><a id="l00112" name="l00112"></a><span class="lineno">  112</span>                    &amp;&amp; abs(eigval_p) + g == abs(eigval_p)</div>
    207. 

  207. <div class="line"><a id="l00113" name="l00113"></a><span class="lineno">  113</span>                    &amp;&amp; abs(eigval_q) + g == abs(eigval_q))</div>
    208. 

  208. <div class="line"><a id="l00114" name="l00114"></a><span class="lineno">  114</span>                {</div>
    209. 

  209. <div class="line"><a id="l00115" name="l00115"></a><span class="lineno">  115</span>                    a_pq = 0.0f;</div>
    210. 

  210. <div class="line"><a id="l00116" name="l00116"></a><span class="lineno">  116</span>                }</div>
    211. 

  211. <div class="line"><a id="l00117" name="l00117"></a><span class="lineno">  117</span>                <span class="keywordflow">else</span> <span class="keywordflow">if</span> (abs_a_pq &gt; thresh)</div>
    212. 

  212. <div class="line"><a id="l00118" name="l00118"></a><span class="lineno">  118</span>                {</div>
    213. 

  213. <div class="line"><a id="l00119" name="l00119"></a><span class="lineno">  119</span>                    <span class="keywordtype">float</span> h = eigval_q - eigval_p;</div>
    214. 

  214. <div class="line"><a id="l00120" name="l00120"></a><span class="lineno">  120</span>                    <span class="keywordtype">float</span> abs_h = abs(h);</div>
    215. 

  215. <div class="line"><a id="l00121" name="l00121"></a><span class="lineno">  121</span> </div>
    216. 

  216. <div class="line"><a id="l00122" name="l00122"></a><span class="lineno">  122</span>                    <span class="keywordtype">float</span> t;</div>
    217. 

  217. <div class="line"><a id="l00123" name="l00123"></a><span class="lineno">  123</span>                    <span class="keywordflow">if</span> (abs_h + g == abs_h)</div>
    218. 

  218. <div class="line"><a id="l00124" name="l00124"></a><span class="lineno">  124</span>                    {</div>
    219. 

  219. <div class="line"><a id="l00125" name="l00125"></a><span class="lineno">  125</span>                        t = a_pq / h;</div>
    220. 

  220. <div class="line"><a id="l00126" name="l00126"></a><span class="lineno">  126</span>                    }</div>
    221. 

  221. <div class="line"><a id="l00127" name="l00127"></a><span class="lineno">  127</span>                    <span class="keywordflow">else</span></div>
    222. 

  222. <div class="line"><a id="l00128" name="l00128"></a><span class="lineno">  128</span>                    {</div>
    223. 

  223. <div class="line"><a id="l00129" name="l00129"></a><span class="lineno">  129</span>                        <span class="keywordtype">float</span> theta = 0.5f * h / a_pq; <span class="comment">// Warning: Can become infinite if a(ip, iq) is very small which may trigger an invalid float exception</span></div>
    224. 

  224. <div class="line"><a id="l00130" name="l00130"></a><span class="lineno">  130</span>                        t = 1.0f / (abs(theta) + sqrt(1.0f + theta * theta)); <span class="comment">// If theta becomes inf, t will be 0 so the infinite is not a problem for the algorithm</span></div>
    225. 

  225. <div class="line"><a id="l00131" name="l00131"></a><span class="lineno">  131</span>                        <span class="keywordflow">if</span> (theta &lt; 0.0f) t = -t;</div>
    226. 

  226. <div class="line"><a id="l00132" name="l00132"></a><span class="lineno">  132</span>                    }</div>
    227. 

  227. <div class="line"><a id="l00133" name="l00133"></a><span class="lineno">  133</span> </div>
    228. 

  228. <div class="line"><a id="l00134" name="l00134"></a><span class="lineno">  134</span>                    <span class="keywordtype">float</span> c = 1.0f / sqrt(1.0f + t * t);</div>
    229. 

  229. <div class="line"><a id="l00135" name="l00135"></a><span class="lineno">  135</span>                    <span class="keywordtype">float</span> s = t * c;</div>
    230. 

  230. <div class="line"><a id="l00136" name="l00136"></a><span class="lineno">  136</span>                    <span class="keywordtype">float</span> tau = s / (1.0f + c);</div>
    231. 

  231. <div class="line"><a id="l00137" name="l00137"></a><span class="lineno">  137</span>                    h = t * a_pq;</div>
    232. 

  232. <div class="line"><a id="l00138" name="l00138"></a><span class="lineno">  138</span> </div>
    233. 

  233. <div class="line"><a id="l00139" name="l00139"></a><span class="lineno">  139</span>                    a_pq = 0.0f;</div>
    234. 

  234. <div class="line"><a id="l00140" name="l00140"></a><span class="lineno">  140</span> </div>
    235. 

  235. <div class="line"><a id="l00141" name="l00141"></a><span class="lineno">  141</span>                    z[ip] -= h;</div>
    236. 

  236. <div class="line"><a id="l00142" name="l00142"></a><span class="lineno">  142</span>                    z[iq] += h;</div>
    237. 

  237. <div class="line"><a id="l00143" name="l00143"></a><span class="lineno">  143</span> </div>
    238. 

  238. <div class="line"><a id="l00144" name="l00144"></a><span class="lineno">  144</span>                    eigval_p -= h;</div>
    239. 

  239. <div class="line"><a id="l00145" name="l00145"></a><span class="lineno">  145</span>                    eigval_q += h;</div>
    240. 

  240. <div class="line"><a id="l00146" name="l00146"></a><span class="lineno">  146</span> </div>
    241. 

  241. <div class="line"><a id="l00147" name="l00147"></a><span class="lineno">  147</span><span class="preprocessor">                    #define JPH_EVS_ROTATE(a, i, j, k, l)       \</span></div>
    242. 

  242. <div class="line"><a id="l00148" name="l00148"></a><span class="lineno">  148</span><span class="preprocessor">                        g = a(i, j),                            \</span></div>
    243. 

  243. <div class="line"><a id="l00149" name="l00149"></a><span class="lineno">  149</span><span class="preprocessor">                        h = a(k, l),                            \</span></div>
    244. 

  244. <div class="line"><a id="l00150" name="l00150"></a><span class="lineno">  150</span><span class="preprocessor">                        a(i, j) = g - s * (h + g * tau),        \</span></div>
    245. 

  245. <div class="line"><a id="l00151" name="l00151"></a><span class="lineno">  151</span><span class="preprocessor">                        a(k, l) = h + s * (g - h * tau)</span></div>
    246. 

  246. <div class="line"><a id="l00152" name="l00152"></a><span class="lineno">  152</span> </div>
    247. 

  247. <div class="line"><a id="l00153" name="l00153"></a><span class="lineno">  153</span>                    <a class="code hl_typedef" href="_core_8h.html#a69aa29b598b851b0640aa225a9e5d61d">uint</a> j;</div>
    248. 

  248. <div class="line"><a id="l00154" name="l00154"></a><span class="lineno">  154</span>                    <span class="keywordflow">for</span> (j = 0; j &lt; ip; ++j)        <a class="code hl_define" href="_eigen_value_symmetric_8h.html#a7de93add3597eb0ea0e78c5cd45f9725">JPH_EVS_ROTATE</a>(a, j, ip, j, iq);</div>
    249. 

  249. <div class="line"><a id="l00155" name="l00155"></a><span class="lineno">  155</span>                    <span class="keywordflow">for</span> (j = ip + 1; j &lt; iq; ++j)   <a class="code hl_define" href="_eigen_value_symmetric_8h.html#a7de93add3597eb0ea0e78c5cd45f9725">JPH_EVS_ROTATE</a>(a, ip, j, j, iq);</div>
    250. 

  250. <div class="line"><a id="l00156" name="l00156"></a><span class="lineno">  156</span>                    <span class="keywordflow">for</span> (j = iq + 1; j &lt; n; ++j)    <a class="code hl_define" href="_eigen_value_symmetric_8h.html#a7de93add3597eb0ea0e78c5cd45f9725">JPH_EVS_ROTATE</a>(a, ip, j, iq, j);</div>
    251. 

  251. <div class="line"><a id="l00157" name="l00157"></a><span class="lineno">  157</span>                    <span class="keywordflow">for</span> (j = 0; j &lt; n; ++j)         <a class="code hl_define" href="_eigen_value_symmetric_8h.html#a7de93add3597eb0ea0e78c5cd45f9725">JPH_EVS_ROTATE</a>(outEigVec, j, ip, j, iq);</div>
    252. 

  252. <div class="line"><a id="l00158" name="l00158"></a><span class="lineno">  158</span> </div>
    253. 

  253. <div class="line"><a id="l00159" name="l00159"></a><span class="lineno">  159</span><span class="preprocessor">                    #undef JPH_EVS_ROTATE</span></div>
    254. 

  254. <div class="line"><a id="l00160" name="l00160"></a><span class="lineno">  160</span>                }</div>
    255. 

  255. <div class="line"><a id="l00161" name="l00161"></a><span class="lineno">  161</span>            }</div>
    256. 

  256. <div class="line"><a id="l00162" name="l00162"></a><span class="lineno">  162</span> </div>
    257. 

  257. <div class="line"><a id="l00163" name="l00163"></a><span class="lineno">  163</span>        <span class="comment">// Update eigenvalues with the sum of ta_pq and reinitialize z</span></div>
    258. 

  258. <div class="line"><a id="l00164" name="l00164"></a><span class="lineno">  164</span>        <span class="keywordflow">for</span> (<a class="code hl_typedef" href="_core_8h.html#a69aa29b598b851b0640aa225a9e5d61d">uint</a> ip = 0; ip &lt; n; ++ip)</div>
    259. 

  259. <div class="line"><a id="l00165" name="l00165"></a><span class="lineno">  165</span>        {</div>
    260. 

  260. <div class="line"><a id="l00166" name="l00166"></a><span class="lineno">  166</span>            b[ip] += z[ip];</div>
    261. 

  261. <div class="line"><a id="l00167" name="l00167"></a><span class="lineno">  167</span>            outEigVal[ip] = b[ip];</div>
    262. 

  262. <div class="line"><a id="l00168" name="l00168"></a><span class="lineno">  168</span>            z[ip] = 0.0f;</div>
    263. 

  263. <div class="line"><a id="l00169" name="l00169"></a><span class="lineno">  169</span>        }</div>
    264. 

  264. <div class="line"><a id="l00170" name="l00170"></a><span class="lineno">  170</span>    }</div>
    265. 

  265. <div class="line"><a id="l00171" name="l00171"></a><span class="lineno">  171</span> </div>
    266. 

  266. <div class="line"><a id="l00172" name="l00172"></a><span class="lineno">  172</span>    <span class="comment">// Failure</span></div>
    267. 

  267. <div class="line"><a id="l00173" name="l00173"></a><span class="lineno">  173</span>    <a class="code hl_define" href="_issue_reporting_8h.html#aaf6b1df827e11b7ca5f6f8778bd8f8cd">JPH_ASSERT</a>(<span class="keyword">false</span>, <span class="stringliteral">&quot;Too many iterations&quot;</span>);</div>
    268. 

  268. <div class="line"><a id="l00174" name="l00174"></a><span class="lineno">  174</span>    <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
    269. 

  269. <div class="line"><a id="l00175" name="l00175"></a><span class="lineno">  175</span>}</div>
    270. 

  270. </div>
    271. 

  271. <div class="line"><a id="l00176" name="l00176"></a><span class="lineno">  176</span> </div>
    272. 

  272. <div class="line"><a id="l00177" name="l00177"></a><span class="lineno">  177</span><a class="code hl_define" href="_core_8h.html#a73da8725998b00321a9db341202d650d">JPH_NAMESPACE_END</a></div>
    273. 

  273. <div class="ttc" id="a_core_8h_html_a69aa29b598b851b0640aa225a9e5d61d"><div class="ttname"><a href="_core_8h.html#a69aa29b598b851b0640aa225a9e5d61d">uint</a></div><div class="ttdeci">unsigned int uint</div><div class="ttdef"><b>Definition</b> Core.h:500</div></div>
    274. 

  274. <div class="ttc" id="a_core_8h_html_a719a73b9e445920bf5969f05d01ce69c"><div class="ttname"><a href="_core_8h.html#a719a73b9e445920bf5969f05d01ce69c">JPH_UNUSED</a></div><div class="ttdeci">#define JPH_UNUSED(x)</div><div class="ttdef"><b>Definition</b> Core.h:597</div></div>
    275. 

  275. <div class="ttc" id="a_core_8h_html_a73da8725998b00321a9db341202d650d"><div class="ttname"><a href="_core_8h.html#a73da8725998b00321a9db341202d650d">JPH_NAMESPACE_END</a></div><div class="ttdeci">#define JPH_NAMESPACE_END</div><div class="ttdef"><b>Definition</b> Core.h:425</div></div>
    276. 

  276. <div class="ttc" id="a_core_8h_html_ad14098b68b8c44ea6112601031268405"><div class="ttname"><a href="_core_8h.html#ad14098b68b8c44ea6112601031268405">JPH_NAMESPACE_BEGIN</a></div><div class="ttdeci">#define JPH_NAMESPACE_BEGIN</div><div class="ttdef"><b>Definition</b> Core.h:419</div></div>
    277. 

  277. <div class="ttc" id="a_eigen_value_symmetric_8h_html_a63488e363acda8a1bd4cd3d297bf4d54"><div class="ttname"><a href="_eigen_value_symmetric_8h.html#a63488e363acda8a1bd4cd3d297bf4d54">EigenValueSymmetric</a></div><div class="ttdeci">JPH_NAMESPACE_BEGIN bool EigenValueSymmetric(const Matrix &amp;inMatrix, Matrix &amp;outEigVec, Vector &amp;outEigVal)</div><div class="ttdef"><b>Definition</b> EigenValueSymmetric.h:29</div></div>
    278. 

  278. <div class="ttc" id="a_eigen_value_symmetric_8h_html_a7de93add3597eb0ea0e78c5cd45f9725"><div class="ttname"><a href="_eigen_value_symmetric_8h.html#a7de93add3597eb0ea0e78c5cd45f9725">JPH_EVS_ROTATE</a></div><div class="ttdeci">#define JPH_EVS_ROTATE(a, i, j, k, l)</div></div>
    279. 

  279. <div class="ttc" id="a_f_p_exception_8h_html"><div class="ttname"><a href="_f_p_exception_8h.html">FPException.h</a></div></div>
    280. 

  280. <div class="ttc" id="a_issue_reporting_8h_html_aaf6b1df827e11b7ca5f6f8778bd8f8cd"><div class="ttname"><a href="_issue_reporting_8h.html#aaf6b1df827e11b7ca5f6f8778bd8f8cd">JPH_ASSERT</a></div><div class="ttdeci">#define JPH_ASSERT(...)</div><div class="ttdef"><b>Definition</b> IssueReporting.h:33</div></div>
    281. 

  281. <div class="ttc" id="a_math_8h_html_a61379b8b743a16fe823daeebc1482570"><div class="ttname"><a href="_math_8h.html#a61379b8b743a16fe823daeebc1482570">Square</a></div><div class="ttdeci">JPH_INLINE constexpr T Square(T inV)</div><div class="ttdoc">Square a value.</div><div class="ttdef"><b>Definition</b> Math.h:55</div></div>
    282. 

  282. <div class="ttc" id="aclass_f_p_exception_disable_invalid_html"><div class="ttname"><a href="class_f_p_exception_disable_invalid.html">FPExceptionDisableInvalid</a></div><div class="ttdef"><b>Definition</b> FPException.h:90</div></div>
    283. 

  283. <div class="ttc" id="aclass_matrix_html"><div class="ttname"><a href="class_matrix.html">Matrix</a></div><div class="ttdoc">Templatized matrix class.</div><div class="ttdef"><b>Definition</b> Matrix.h:15</div></div>
    284. 

  284. <div class="ttc" id="aclass_matrix_html_a295baf4af956351b6bf05548e16887ee"><div class="ttname"><a href="class_matrix.html#a295baf4af956351b6bf05548e16887ee">Matrix::GetRows</a></div><div class="ttdeci">uint GetRows() const</div><div class="ttdoc">Dimensions.</div><div class="ttdef"><b>Definition</b> Matrix.h:22</div></div>
    285. 

  285. <div class="ttc" id="aclass_matrix_html_a35353d8c2a5a249e5368e654bca5fc79"><div class="ttname"><a href="class_matrix.html#a35353d8c2a5a249e5368e654bca5fc79">Matrix::IsIdentity</a></div><div class="ttdeci">bool IsIdentity() const</div><div class="ttdoc">Check if this matrix is identity.</div><div class="ttdef"><b>Definition</b> Matrix.h:58</div></div>
    286. 

  286. <div class="ttc" id="aclass_matrix_html_a45bd49a18dec51ca82c58aa5d12572be"><div class="ttname"><a href="class_matrix.html#a45bd49a18dec51ca82c58aa5d12572be">Matrix::GetCols</a></div><div class="ttdeci">uint GetCols() const</div><div class="ttdef"><b>Definition</b> Matrix.h:23</div></div>
    287. 

  287. <div class="ttc" id="aclass_matrix_html_a92a370676cc7e0788bc217a358170b4a"><div class="ttname"><a href="class_matrix.html#a92a370676cc7e0788bc217a358170b4a">Matrix::GetColumn</a></div><div class="ttdeci">const Vector&lt; Rows &gt; &amp; GetColumn(int inIdx) const</div><div class="ttdoc">Column access.</div><div class="ttdef"><b>Definition</b> Matrix.h:225</div></div>
    288. 

  288. <div class="ttc" id="aclass_vector_html"><div class="ttname"><a href="class_vector.html">Vector</a></div><div class="ttdoc">Templatized vector class.</div><div class="ttdef"><b>Definition</b> Vector.h:12</div></div>
    289. 

  289. <div class="ttc" id="aclass_vector_html_a5e282c7195754fe9b4864ba772e3cad9"><div class="ttname"><a href="class_vector.html#a5e282c7195754fe9b4864ba772e3cad9">Vector::IsClose</a></div><div class="ttdeci">bool IsClose(const Vector &amp;inV2, float inMaxDistSq=1.0e-12f) const</div><div class="ttdoc">Test if two vectors are close to each other.</div><div class="ttdef"><b>Definition</b> Vector.h:78</div></div>
    290. 

  290. <div class="ttc" id="aclass_vector_html_a8c1387fdaa60b9569f5e9acb1363b7fb"><div class="ttname"><a href="class_vector.html#a8c1387fdaa60b9569f5e9acb1363b7fb">Vector::GetRows</a></div><div class="ttdeci">uint GetRows() const</div><div class="ttdoc">Dimensions.</div><div class="ttdef"><b>Definition</b> Vector.h:19</div></div>
    291. 

  291. <div class="ttc" id="aclass_vector_html_afa80dcde530acc7b7911526d921b60e8"><div class="ttname"><a href="class_vector.html#afa80dcde530acc7b7911526d921b60e8">Vector::LengthSq</a></div><div class="ttdeci">float LengthSq() const</div><div class="ttdoc">Squared length of vector.</div><div class="ttdef"><b>Definition</b> Vector.h:175</div></div>
    292. 

  292. </div><!-- fragment --></div><!-- contents -->
    293. 

  293. </div><!-- doc-content -->
    294. 

  294. <!-- start footer part -->
    295. 

  295. <div id="nav-path" class="navpath"><!-- id is needed for treeview function! -->
    296. 

  296.   <ul>
    297. 

  297.     <li class="navelem"><a class="el" href="dir_d99289a5d3c46cf26f14ff6c90658d9f.html">Jolt</a></li><li class="navelem"><a class="el" href="dir_aa37033c5611f3a5cff668cf59181100.html">Math</a></li><li class="navelem"><a class="el" href="_eigen_value_symmetric_8h.html">EigenValueSymmetric.h</a></li>
    298. 

  298.     <li class="footer">Generated by <a href="https://www.doxygen.org/index.html"><img class="footer" src="doxygen.svg" width="104" height="31" alt="doxygen"/></a> 1.12.0 </li>
    299. 

  299.   </ul>
    300. 

  300. </div>
    301. 

  301. </body>
    302. 

  302. </html>
    303.