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<a href="#func-members">Functions</a> &#124;
<a href="#var-members">Variables</a> </div>
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<h1>Sine Cosine<br/>
<small>
[<a class="el" href="group__group_controller.html">Controller Functions</a>]</small>
</h1> </div>
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<div class="contents">
<table class="memberdecls">
<tr><td colspan="2"><h2><a name="func-members"></a>
Functions</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___sin_cos.html#ga4420d45c37d58c310ef9ae1b5fe58020">arm_sin_cos_f32</a> (<a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> theta, <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> *pSinVal, <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> *pCosVal)</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___sin_cos.html#gae9e4ddebff9d4eb5d0a093e28e0bc504">arm_sin_cos_q31</a> (<a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> theta, <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> *pSinVal, <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> *pCosVal)</td></tr>
<tr><td colspan="2"><h2><a name="var-members"></a>
Variables</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">static const <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___sin_cos.html#ga73d46b72b2e2e5c3301adb7a8a7cab5e">cosTable</a> [360]</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">static const <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___sin_cos.html#ga2e70480fd73eae93d51a6e881bb1f2e4">sinTable</a> [360]</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">static const int32_t&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___sin_cos.html#ga77c2ec4c8f210d254ef0fbeea0bdf067">sinTableQ31</a> [360]</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">static const int32_t&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___sin_cos.html#gab3ca1fd1431d146c6bde7d39dd7e903d">cosTableQ31</a> [360]</td></tr>
</table>
<hr/><a name="_details"></a><h2>Detailed Description</h2>
<p>Computes the trigonometric sine and cosine values using a combination of table lookup and linear interpolation. There are separate functions for Q31 and floating-point data types. The input to the floating-point version is in degrees while the fixed-point Q31 have a scaled input with the range [-1 1) mapping to [-180 180) degrees.</p>
<p>The implementation is based on table lookup using 360 values together with linear interpolation. The steps used are:</p>
<ol type="1">
<li>Calculation of the nearest integer table index.</li>
<li>Compute the fractional portion (fract) of the input.</li>
<li>Fetch the value corresponding to <code>index</code> from sine table to <code>y0</code> and also value from <code>index+1</code> to <code>y1</code>.</li>
<li>Sine value is computed as <code> *psinVal = y0 + (fract * (y1 - y0))</code>.</li>
<li>Fetch the value corresponding to <code>index</code> from cosine table to <code>y0</code> and also value from <code>index+1</code> to <code>y1</code>.</li>
<li>Cosine value is computed as <code> *pcosVal = y0 + (fract * (y1 - y0))</code>. </li>
</ol>
<hr/><h2>Function Documentation</h2>
<a class="anchor" id="ga4420d45c37d58c310ef9ae1b5fe58020"></a><!-- doxytag: member="arm_sin_cos_f32.c::arm_sin_cos_f32" ref="ga4420d45c37d58c310ef9ae1b5fe58020" args="(float32_t theta, float32_t *pSinVal, float32_t *pCosVal)" -->
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<td class="memname">void arm_sin_cos_f32 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a>&#160;</td>
<td class="paramname"> <em>theta</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> *&#160;</td>
<td class="paramname"> <em>pSinVal</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> *&#160;</td>
<td class="paramname"> <em>pCosVal</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
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<div class="memdoc">
<p>Floating-point sin_cos function. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramdir">[in]</td><td class="paramname">theta</td><td>input value in degrees </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">*pSinVal</td><td>points to the processed sine output. </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">*pCosVal</td><td>points to the processed cos output. </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>none. </dd></dl>
<p>Definition at line <a class="el" href="arm__sin__cos__f32_8c_source.html#l00367">367</a> of file <a class="el" href="arm__sin__cos__f32_8c_source.html">arm_sin_cos_f32.c</a>.</p>
</div>
</div>
<a class="anchor" id="gae9e4ddebff9d4eb5d0a093e28e0bc504"></a><!-- doxytag: member="arm_sin_cos_q31.c::arm_sin_cos_q31" ref="gae9e4ddebff9d4eb5d0a093e28e0bc504" args="(q31_t theta, q31_t *pSinVal, q31_t *pCosVal)" -->
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<td class="memname">void arm_sin_cos_q31 </td>
<td>(</td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a>&#160;</td>
<td class="paramname"> <em>theta</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> *&#160;</td>
<td class="paramname"> <em>pSinVal</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> *&#160;</td>
<td class="paramname"> <em>pCosVal</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div>
<div class="memdoc">
<p>Q31 sin_cos function. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table class="params">
<tr><td class="paramdir">[in]</td><td class="paramname">theta</td><td>scaled input value in degrees </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">*pSinVal</td><td>points to the processed sine output. </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">*pCosVal</td><td>points to the processed cosine output. </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>none.</dd></dl>
<p>The Q31 input value is in the range [-1 +1) and is mapped to a degree value in the range [-180 180). </p>
<p>Definition at line <a class="el" href="arm__sin__cos__q31_8c_source.html#l00264">264</a> of file <a class="el" href="arm__sin__cos__q31_8c_source.html">arm_sin_cos_q31.c</a>.</p>
</div>
</div>
<hr/><h2>Variable Documentation</h2>
<a class="anchor" id="ga73d46b72b2e2e5c3301adb7a8a7cab5e"></a><!-- doxytag: member="arm_sin_cos_f32.c::cosTable" ref="ga73d46b72b2e2e5c3301adb7a8a7cab5e" args="[360]" -->
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<td class="memname">const <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> <a class="el" href="group__cos.html#ga9588015a9447c6e124d36339e273bd53">cosTable</a>[360]<code> [static]</code></td>
</tr>
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</div>
<div class="memdoc">
<dl class="user"><dt><b></b></dt><dd>Cosine Table is generated from following loop <pre>for(i = 0; i &lt; 360; i++)
{
cosTable[i]= cos((i-180) * PI/180.0);
} </pre> </dd></dl>
<p>Definition at line <a class="el" href="arm__sin__cos__f32_8c_source.html#l00071">71</a> of file <a class="el" href="arm__sin__cos__f32_8c_source.html">arm_sin_cos_f32.c</a>.</p>
</div>
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<a class="anchor" id="ga2e70480fd73eae93d51a6e881bb1f2e4"></a><!-- doxytag: member="arm_sin_cos_f32.c::sinTable" ref="ga2e70480fd73eae93d51a6e881bb1f2e4" args="[360]" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
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<td class="memname">const <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> <a class="el" href="group__sin.html#ga71a0a466c6d42c65526968509b04790c">sinTable</a>[360]<code> [static]</code></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl class="user"><dt><b></b></dt><dd>Sine Table is generated from following loop <pre>for(i = 0; i &lt; 360; i++)
{
sinTable[i]= sin((i-180) * PI/180.0);
} </pre> </dd></dl>
<p>Definition at line <a class="el" href="arm__sin__cos__f32_8c_source.html#l00219">219</a> of file <a class="el" href="arm__sin__cos__f32_8c_source.html">arm_sin_cos_f32.c</a>.</p>
</div>
</div>
<a class="anchor" id="ga77c2ec4c8f210d254ef0fbeea0bdf067"></a><!-- doxytag: member="arm_sin_cos_q31.c::sinTableQ31" ref="ga77c2ec4c8f210d254ef0fbeea0bdf067" args="[360]" -->
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<td class="memname">const int32_t <a class="el" href="group__sin.html#gab1ffde7f3deee5adc75ba8b3d0a53106">sinTableQ31</a>[360]<code> [static]</code></td>
</tr>
</table>
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<div class="memdoc">
<dl class="user"><dt><b></b></dt><dd>Sine Table is generated from following loop <pre>for(i = 0; i &lt; 360; i++)
{
sinTable[i]= sin((i-180) * PI/180.0);
} </pre> Convert above coefficients to fixed point 1.31 format. </dd></dl>
<p>Definition at line <a class="el" href="arm__sin__cos__q31_8c_source.html#l00051">51</a> of file <a class="el" href="arm__sin__cos__q31_8c_source.html">arm_sin_cos_q31.c</a>.</p>
</div>
</div>
<a class="anchor" id="gab3ca1fd1431d146c6bde7d39dd7e903d"></a><!-- doxytag: member="arm_sin_cos_q31.c::cosTableQ31" ref="gab3ca1fd1431d146c6bde7d39dd7e903d" args="[360]" -->
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">const int32_t <a class="el" href="group__cos.html#gafe999a5fcf1774a2292220071096b834">cosTableQ31</a>[360]<code> [static]</code></td>
</tr>
</table>
</div>
<div class="memdoc">
<dl class="user"><dt><b></b></dt><dd>Cosine Table is generated from following loop <pre>for(i = 0; i &lt; 360; i++)
{
cosTable[i]= cos((i-180) * PI/180.0);
} </pre> </dd></dl>
<dl class="user"><dt><b></b></dt><dd>Convert above coefficients to fixed point 1.31 format. </dd></dl>
<p>Definition at line <a class="el" href="arm__sin__cos__q31_8c_source.html#l00157">157</a> of file <a class="el" href="arm__sin__cos__q31_8c_source.html">arm_sin_cos_q31.c</a>.</p>
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