<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://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 1.8.3"/> <title>GNU Radio 3.6.4.1 C++ API: gr_fxpt.h Source File</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="navtree.js"></script> <script type="text/javascript"> $(document).ready(initResizable); $(window).load(resizeHeight); </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 style="padding-left: 0.5em;"> <div id="projectname">GNU Radio 3.6.4.1 C++ API </div> </td> </tr> </tbody> </table> </div> <!-- end header part --> <!-- Generated by Doxygen 1.8.3 --> </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"> $(document).ready(function(){initNavTree('gr__fxpt_8h_source.html','');}); </script> <div id="doc-content"> <div class="header"> <div class="headertitle"> <div class="title">gr_fxpt.h</div> </div> </div><!--header--> <div class="contents"> <a href="gr__fxpt_8h.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="comment">/* -*- c++ -*- */</span></div> <div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment">/*</span></div> <div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment"> * Copyright 2004 Free Software Foundation, Inc.</span></div> <div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment"> *</span></div> <div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="comment"> * This file is part of GNU Radio</span></div> <div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="comment"> *</span></div> <div class="line"><a name="l00007"></a><span class="lineno"> 7</span> <span class="comment"> * GNU Radio is free software; you can redistribute it and/or modify</span></div> <div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="comment"> * it under the terms of the GNU General Public License as published by</span></div> <div class="line"><a name="l00009"></a><span class="lineno"> 9</span> <span class="comment"> * the Free Software Foundation; either version 3, or (at your option)</span></div> <div class="line"><a name="l00010"></a><span class="lineno"> 10</span> <span class="comment"> * any later version.</span></div> <div class="line"><a name="l00011"></a><span class="lineno"> 11</span> <span class="comment"> *</span></div> <div class="line"><a name="l00012"></a><span class="lineno"> 12</span> <span class="comment"> * GNU Radio is distributed in the hope that it will be useful,</span></div> <div class="line"><a name="l00013"></a><span class="lineno"> 13</span> <span class="comment"> * but WITHOUT ANY WARRANTY; without even the implied warranty of</span></div> <div class="line"><a name="l00014"></a><span class="lineno"> 14</span> <span class="comment"> * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the</span></div> <div class="line"><a name="l00015"></a><span class="lineno"> 15</span> <span class="comment"> * GNU General Public License for more details.</span></div> <div class="line"><a name="l00016"></a><span class="lineno"> 16</span> <span class="comment"> *</span></div> <div class="line"><a name="l00017"></a><span class="lineno"> 17</span> <span class="comment"> * You should have received a copy of the GNU General Public License</span></div> <div class="line"><a name="l00018"></a><span class="lineno"> 18</span> <span class="comment"> * along with GNU Radio; see the file COPYING. If not, write to</span></div> <div class="line"><a name="l00019"></a><span class="lineno"> 19</span> <span class="comment"> * the Free Software Foundation, Inc., 51 Franklin Street,</span></div> <div class="line"><a name="l00020"></a><span class="lineno"> 20</span> <span class="comment"> * Boston, MA 02110-1301, USA.</span></div> <div class="line"><a name="l00021"></a><span class="lineno"> 21</span> <span class="comment"> */</span></div> <div class="line"><a name="l00022"></a><span class="lineno"> 22</span> <span class="preprocessor">#ifndef INCLUDED_GR_FXPT_H</span></div> <div class="line"><a name="l00023"></a><span class="lineno"> 23</span> <span class="preprocessor"></span><span class="preprocessor">#define INCLUDED_GR_FXPT_H</span></div> <div class="line"><a name="l00024"></a><span class="lineno"> 24</span> <span class="preprocessor"></span></div> <div class="line"><a name="l00025"></a><span class="lineno"> 25</span> <span class="preprocessor">#include <<a class="code" href="gr__core__api_8h.html">gr_core_api.h</a>></span></div> <div class="line"><a name="l00026"></a><span class="lineno"> 26</span> <span class="preprocessor">#include <<a class="code" href="gr__types_8h.html">gr_types.h</a>></span></div> <div class="line"><a name="l00027"></a><span class="lineno"> 27</span> <span class="comment"></span></div> <div class="line"><a name="l00028"></a><span class="lineno"> 28</span> <span class="comment">/*!</span></div> <div class="line"><a name="l00029"></a><span class="lineno"> 29</span> <span class="comment"> * \brief fixed point sine and cosine and friends.</span></div> <div class="line"><a name="l00030"></a><span class="lineno"> 30</span> <span class="comment"> * \ingroup misc</span></div> <div class="line"><a name="l00031"></a><span class="lineno"> 31</span> <span class="comment"> *</span></div> <div class="line"><a name="l00032"></a><span class="lineno"> 32</span> <span class="comment"> * fixed pt radians</span></div> <div class="line"><a name="l00033"></a><span class="lineno"> 33</span> <span class="comment"> * --------- --------</span></div> <div class="line"><a name="l00034"></a><span class="lineno"> 34</span> <span class="comment"> * -2**31 -pi</span></div> <div class="line"><a name="l00035"></a><span class="lineno"> 35</span> <span class="comment"> * 0 0</span></div> <div class="line"><a name="l00036"></a><span class="lineno"> 36</span> <span class="comment"> * 2**31-1 pi - epsilon</span></div> <div class="line"><a name="l00037"></a><span class="lineno"> 37</span> <span class="comment"> *</span></div> <div class="line"><a name="l00038"></a><span class="lineno"> 38</span> <span class="comment"> */</span></div> <div class="line"><a name="l00039"></a><span class="lineno"><a class="code" href="classgr__fxpt.html"> 39</a></span> <span class="keyword">class </span><a class="code" href="gr__core__api_8h.html#a8b8937b0c61edd85ab57ce8203543248">GR_CORE_API</a> <a class="code" href="classgr__fxpt.html" title="fixed point sine and cosine and friends.fixed pt radians -2**31 -pi 0 0 2**31-1 pi - epsilon...">gr_fxpt</a></div> <div class="line"><a name="l00040"></a><span class="lineno"> 40</span> {</div> <div class="line"><a name="l00041"></a><span class="lineno"> 41</span>  <span class="keyword">static</span> <span class="keyword">const</span> <span class="keywordtype">int</span> WORDBITS = 32;</div> <div class="line"><a name="l00042"></a><span class="lineno"> 42</span>  <span class="keyword">static</span> <span class="keyword">const</span> <span class="keywordtype">int</span> NBITS = 10;</div> <div class="line"><a name="l00043"></a><span class="lineno"> 43</span>  <span class="keyword">static</span> <span class="keyword">const</span> <span class="keywordtype">float</span> s_sine_table[1 << NBITS][2];</div> <div class="line"><a name="l00044"></a><span class="lineno"> 44</span>  <span class="keyword">static</span> <span class="keyword">const</span> <span class="keywordtype">float</span> <a class="code" href="defines_8h.html#a598a3330b3c21701223ee0ca14316eca">PI</a>;</div> <div class="line"><a name="l00045"></a><span class="lineno"> 45</span>  <span class="keyword">static</span> <span class="keyword">const</span> <span class="keywordtype">float</span> TWO_TO_THE_31;</div> <div class="line"><a name="l00046"></a><span class="lineno"> 46</span> <span class="keyword">public</span>:</div> <div class="line"><a name="l00047"></a><span class="lineno"> 47</span> </div> <div class="line"><a name="l00048"></a><span class="lineno"> 48</span>  <span class="keyword">static</span> <a class="code" href="gr__types_8h.html#ac07cda22882f844c0aa1633d49f1c144">gr_int32</a></div> <div class="line"><a name="l00049"></a><span class="lineno"><a class="code" href="classgr__fxpt.html#a8cf5f6942dd8db09072fb711d09b4820"> 49</a></span>  float_to_fixed (<span class="keywordtype">float</span> x)</div> <div class="line"><a name="l00050"></a><span class="lineno"> 50</span>  {</div> <div class="line"><a name="l00051"></a><span class="lineno"> 51</span>  <span class="comment">// Fold x into -PI to PI.</span></div> <div class="line"><a name="l00052"></a><span class="lineno"> 52</span>  <span class="keywordtype">int</span> d = (int)floor(x/2/<a class="code" href="defines_8h.html#a598a3330b3c21701223ee0ca14316eca">PI</a>+0.5);</div> <div class="line"><a name="l00053"></a><span class="lineno"> 53</span>  x -= d*2*<a class="code" href="defines_8h.html#a598a3330b3c21701223ee0ca14316eca">PI</a>;</div> <div class="line"><a name="l00054"></a><span class="lineno"> 54</span>  <span class="comment">// And convert to an integer.</span></div> <div class="line"><a name="l00055"></a><span class="lineno"> 55</span>  <span class="keywordflow">return</span> (<a class="code" href="gr__types_8h.html#ac07cda22882f844c0aa1633d49f1c144">gr_int32</a>) ((float) x * TWO_TO_THE_31 / PI);</div> <div class="line"><a name="l00056"></a><span class="lineno"> 56</span>  }</div> <div class="line"><a name="l00057"></a><span class="lineno"> 57</span> </div> <div class="line"><a name="l00058"></a><span class="lineno"> 58</span>  <span class="keyword">static</span> <span class="keywordtype">float</span></div> <div class="line"><a name="l00059"></a><span class="lineno"><a class="code" href="classgr__fxpt.html#a4b89af0770b5c4751f52224976514c20"> 59</a></span>  fixed_to_float (<a class="code" href="gr__types_8h.html#ac07cda22882f844c0aa1633d49f1c144">gr_int32</a> x)</div> <div class="line"><a name="l00060"></a><span class="lineno"> 60</span>  {</div> <div class="line"><a name="l00061"></a><span class="lineno"> 61</span>  <span class="keywordflow">return</span> x * (<a class="code" href="defines_8h.html#a598a3330b3c21701223ee0ca14316eca">PI</a> / TWO_TO_THE_31);</div> <div class="line"><a name="l00062"></a><span class="lineno"> 62</span>  }</div> <div class="line"><a name="l00063"></a><span class="lineno"> 63</span> <span class="comment"></span></div> <div class="line"><a name="l00064"></a><span class="lineno"> 64</span> <span class="comment"> /*!</span></div> <div class="line"><a name="l00065"></a><span class="lineno"> 65</span> <span class="comment"> * \brief Given a fixed point angle x, return float sine (x)</span></div> <div class="line"><a name="l00066"></a><span class="lineno"> 66</span> <span class="comment"> */</span></div> <div class="line"><a name="l00067"></a><span class="lineno"> 67</span>  <span class="keyword">static</span> <span class="keywordtype">float</span></div> <div class="line"><a name="l00068"></a><span class="lineno"><a class="code" href="classgr__fxpt.html#a26312e3f31f6d7a6ae4810c05f30979a"> 68</a></span>  sin (<a class="code" href="gr__types_8h.html#ac07cda22882f844c0aa1633d49f1c144">gr_int32</a> x)</div> <div class="line"><a name="l00069"></a><span class="lineno"> 69</span>  {</div> <div class="line"><a name="l00070"></a><span class="lineno"> 70</span>  <a class="code" href="gr__types_8h.html#a89e5afa41619bc5b0694d38709297d47">gr_uint32</a> ux = x;</div> <div class="line"><a name="l00071"></a><span class="lineno"> 71</span>  <span class="keywordtype">int</span> index = ux >> (WORDBITS - NBITS);</div> <div class="line"><a name="l00072"></a><span class="lineno"> 72</span>  <span class="keywordflow">return</span> s_sine_table[index][0] * (ux >> 1) + s_sine_table[index][1];</div> <div class="line"><a name="l00073"></a><span class="lineno"> 73</span>  }</div> <div class="line"><a name="l00074"></a><span class="lineno"> 74</span> </div> <div class="line"><a name="l00075"></a><span class="lineno"> 75</span>  <span class="comment">/*</span></div> <div class="line"><a name="l00076"></a><span class="lineno"> 76</span> <span class="comment"> * \brief Given a fixed point angle x, return float cosine (x)</span></div> <div class="line"><a name="l00077"></a><span class="lineno"> 77</span> <span class="comment"> */</span></div> <div class="line"><a name="l00078"></a><span class="lineno"> 78</span>  <span class="keyword">static</span> <span class="keywordtype">float</span></div> <div class="line"><a name="l00079"></a><span class="lineno"><a class="code" href="classgr__fxpt.html#a61861c9e4535e05a567a96a2551430a9"> 79</a></span>  cos (<a class="code" href="gr__types_8h.html#ac07cda22882f844c0aa1633d49f1c144">gr_int32</a> x)</div> <div class="line"><a name="l00080"></a><span class="lineno"> 80</span>  {</div> <div class="line"><a name="l00081"></a><span class="lineno"> 81</span>  <a class="code" href="gr__types_8h.html#a89e5afa41619bc5b0694d38709297d47">gr_uint32</a> ux = x + 0x40000000;</div> <div class="line"><a name="l00082"></a><span class="lineno"> 82</span>  <span class="keywordtype">int</span> index = ux >> (WORDBITS - NBITS);</div> <div class="line"><a name="l00083"></a><span class="lineno"> 83</span>  <span class="keywordflow">return</span> s_sine_table[index][0] * (ux >> 1) + s_sine_table[index][1];</div> <div class="line"><a name="l00084"></a><span class="lineno"> 84</span>  }</div> <div class="line"><a name="l00085"></a><span class="lineno"> 85</span> </div> <div class="line"><a name="l00086"></a><span class="lineno"> 86</span>  <span class="comment">/*</span></div> <div class="line"><a name="l00087"></a><span class="lineno"> 87</span> <span class="comment"> * \brief Given a fixedpoint angle x, return float cos(x) and sin (x)</span></div> <div class="line"><a name="l00088"></a><span class="lineno"> 88</span> <span class="comment"> */</span></div> <div class="line"><a name="l00089"></a><span class="lineno"><a class="code" href="classgr__fxpt.html#aee55c2ee476ef0c90aadd6084d01eefa"> 89</a></span>  <span class="keyword">static</span> <span class="keywordtype">void</span> <a class="code" href="namespacegr_1_1analog.html#a409c8e7fc9481eb9d5a2e1e0d9466778">sincos</a>(<a class="code" href="gr__types_8h.html#ac07cda22882f844c0aa1633d49f1c144">gr_int32</a> x, <span class="keywordtype">float</span> *s, <span class="keywordtype">float</span> *c)</div> <div class="line"><a name="l00090"></a><span class="lineno"> 90</span>  {</div> <div class="line"><a name="l00091"></a><span class="lineno"> 91</span>  <a class="code" href="gr__types_8h.html#a89e5afa41619bc5b0694d38709297d47">gr_uint32</a> ux = x;</div> <div class="line"><a name="l00092"></a><span class="lineno"> 92</span>  <span class="keywordtype">int</span> sin_index = ux >> (WORDBITS - NBITS);</div> <div class="line"><a name="l00093"></a><span class="lineno"> 93</span>  *s = s_sine_table[sin_index][0] * (ux >> 1) + s_sine_table[sin_index][1];</div> <div class="line"><a name="l00094"></a><span class="lineno"> 94</span> </div> <div class="line"><a name="l00095"></a><span class="lineno"> 95</span>  ux = x + 0x40000000;</div> <div class="line"><a name="l00096"></a><span class="lineno"> 96</span>  <span class="keywordtype">int</span> cos_index = ux >> (WORDBITS - NBITS);</div> <div class="line"><a name="l00097"></a><span class="lineno"> 97</span>  *c = s_sine_table[cos_index][0] * (ux >> 1) + s_sine_table[cos_index][1];</div> <div class="line"><a name="l00098"></a><span class="lineno"> 98</span> </div> <div class="line"><a name="l00099"></a><span class="lineno"> 99</span>  <span class="keywordflow">return</span>;</div> <div class="line"><a name="l00100"></a><span class="lineno"> 100</span>  }</div> <div class="line"><a name="l00101"></a><span class="lineno"> 101</span> </div> <div class="line"><a name="l00102"></a><span class="lineno"> 102</span> };</div> <div class="line"><a name="l00103"></a><span class="lineno"> 103</span> </div> <div class="line"><a name="l00104"></a><span class="lineno"> 104</span> <span class="preprocessor">#endif </span><span class="comment">/* INCLUDED_GR_FXPT_H */</span><span class="preprocessor"></span></div> </div><!-- fragment --></div><!-- contents --> </div><!-- doc-content --> <!-- start footer part --> <div id="nav-path" class="navpath"><!-- id is needed for treeview function! --> <ul> <li class="navelem"><a class="el" href="dir_284717b6cb06147531c058220802c6d1.html">gnuradio-core</a></li><li class="navelem"><a class="el" href="dir_7c24473031c549da670035bb20d1e97e.html">src</a></li><li class="navelem"><a class="el" href="dir_84906bae47c76101f1fa015cf813f8a2.html">lib</a></li><li class="navelem"><a class="el" href="dir_a82a9d947ffcded01cd668b1a1a6c872.html">general</a></li><li class="navelem"><a class="el" href="gr__fxpt_8h.html">gr_fxpt.h</a></li> <li class="footer">Generated on Fri Apr 19 2013 16:20:33 for GNU Radio 3.6.4.1 C++ API by <a href="http://www.doxygen.org/index.html"> <img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.8.3 </li> </ul> </div> </body> </html>