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  45 <a href="#func-members">Functions</a>  </div>
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  47 <h1>Square Root<br/>
  48 <small>
  49 [<a class="el" href="group__group_fast_math.html">Fast Math Functions</a>]</small>
  50 </h1>  </div>
  51 </div>
  52 <div class="contents">
  53 <table class="memberdecls">
  54 <tr><td colspan="2"><h2><a name="func-members"></a>
  55 Functions</h2></td></tr>
  56 <tr><td class="memItemLeft" align="right" valign="top"><a class="el" href="arm__math_8h.html#a5e459c6409dfcd2927bb8a57491d7cf6">arm_status</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___s_q_r_t.html#ga119e25831e141d734d7ef10636670058">arm_sqrt_q31</a> (<a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> in, <a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> *pOut)</td></tr>
  57 <tr><td class="memItemLeft" align="right" valign="top"><a class="el" href="arm__math_8h.html#a5e459c6409dfcd2927bb8a57491d7cf6">arm_status</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___s_q_r_t.html#ga5abe5ca724f3e15849662b03752c1238">arm_sqrt_q15</a> (<a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> in, <a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> *pOut)</td></tr>
  58 <tr><td class="memItemLeft" align="right" valign="top">static __INLINE <a class="el" href="arm__math_8h.html#a5e459c6409dfcd2927bb8a57491d7cf6">arm_status</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="group___s_q_r_t.html#ga56a40d1cf842b0b45267df6761975da0">arm_sqrt_f32</a> (<a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> in, <a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> *pOut)</td></tr>
  59 </table>
  60 <hr/><a name="_details"></a><h2>Detailed Description</h2>
  61 <p>Computes the square root of a number. There are separate functions for Q15, Q31, and floating-point data types. The square root function is computed using the Newton-Raphson algorithm. This is an iterative algorithm of the form: </p>
  62 <pre>
  63       x1 = x0 - f(x0)/f'(x0)
  64  </pre><p> where <code>x1</code> is the current estimate, <code>x0</code> is the previous estimate and <code>f'(x0)</code> is the derivative of <code>f()</code> evaluated at <code>x0</code>. For the square root function, the algorithm reduces to: </p>
  65 <pre>
  66      x0 = in/2                         [initial guess]
  67      x1 = 1/2 * ( x0 + in / x0)        [each iteration]
  68  </pre> <hr/><h2>Function Documentation</h2>
  69 <a class="anchor" id="ga119e25831e141d734d7ef10636670058"></a><!-- doxytag: member="arm_sqrt_q31.c::arm_sqrt_q31" ref="ga119e25831e141d734d7ef10636670058" args="(q31_t in, q31_t *pOut)" -->
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  71 <div class="memproto">
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  73         <tr>
  74           <td class="memname"><a class="el" href="arm__math_8h.html#a5e459c6409dfcd2927bb8a57491d7cf6">arm_status</a> arm_sqrt_q31 </td>
  75           <td>(</td>
  76           <td class="paramtype"><a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a>&#160;</td>
  77           <td class="paramname"> <em>in</em>, </td>
  78         </tr>
  79         <tr>
  80           <td class="paramkey"></td>
  81           <td></td>
  82           <td class="paramtype"><a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> *&#160;</td>
  83           <td class="paramname"> <em>pOut</em>&#160;</td>
  84         </tr>
  85         <tr>
  86           <td></td>
  87           <td>)</td>
  88           <td></td><td></td>
  89         </tr>
  90       </table>
  91 </div>
  92 <div class="memdoc">
  93
  94 <p>Q31 square root function. </p>
  95 <dl><dt><b>Parameters:</b></dt><dd>
  96   <table class="params">
  97     <tr><td class="paramdir">[in]</td><td class="paramname">in</td><td>input value. The range of the input value is [0 +1) or 0x00000000 to 0x7FFFFFFF. </td></tr>
  98     <tr><td class="paramdir">[out]</td><td class="paramname">*pOut</td><td>square root of input value. </td></tr>
  99   </table>
 100   </dd>
 101 </dl>
 102 <dl class="return"><dt><b>Returns:</b></dt><dd>The function returns ARM_MATH_SUCCESS if input value is positive value or ARM_MATH_ARGUMENT_ERROR if <code>in</code> is negative value and returns zero output for negative values. </dd></dl>
 103
 104 <p>Definition at line <a class="el" href="arm__sqrt__q31_8c_source.html#l00047">47</a> of file <a class="el" href="arm__sqrt__q31_8c_source.html">arm_sqrt_q31.c</a>.</p>
 105
 106 </div>
 107 </div>
 108 <a class="anchor" id="ga5abe5ca724f3e15849662b03752c1238"></a><!-- doxytag: member="arm_sqrt_q15.c::arm_sqrt_q15" ref="ga5abe5ca724f3e15849662b03752c1238" args="(q15_t in, q15_t *pOut)" -->
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 110 <div class="memproto">
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 112         <tr>
 113           <td class="memname"><a class="el" href="arm__math_8h.html#a5e459c6409dfcd2927bb8a57491d7cf6">arm_status</a> arm_sqrt_q15 </td>
 114           <td>(</td>
 115           <td class="paramtype"><a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a>&#160;</td>
 116           <td class="paramname"> <em>in</em>, </td>
 117         </tr>
 118         <tr>
 119           <td class="paramkey"></td>
 120           <td></td>
 121           <td class="paramtype"><a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> *&#160;</td>
 122           <td class="paramname"> <em>pOut</em>&#160;</td>
 123         </tr>
 124         <tr>
 125           <td></td>
 126           <td>)</td>
 127           <td></td><td></td>
 128         </tr>
 129       </table>
 130 </div>
 131 <div class="memdoc">
 132
 133 <p>Q15 square root function. </p>
 134 <dl><dt><b>Parameters:</b></dt><dd>
 135   <table class="params">
 136     <tr><td class="paramdir">[in]</td><td class="paramname">in</td><td>input value. The range of the input value is [0 +1) or 0x0000 to 0x7FFF. </td></tr>
 137     <tr><td class="paramdir">[out]</td><td class="paramname">*pOut</td><td>square root of input value. </td></tr>
 138   </table>
 139   </dd>
 140 </dl>
 141 <dl class="return"><dt><b>Returns:</b></dt><dd>The function returns ARM_MATH_SUCCESS if input value is positive value or ARM_MATH_ARGUMENT_ERROR if <code>in</code> is negative value and returns zero output for negative values. </dd></dl>
 142
 143 <p>Definition at line <a class="el" href="arm__sqrt__q15_8c_source.html#l00051">51</a> of file <a class="el" href="arm__sqrt__q15_8c_source.html">arm_sqrt_q15.c</a>.</p>
 144
 145 </div>
 146 </div>
 147 <a class="anchor" id="ga56a40d1cf842b0b45267df6761975da0"></a><!-- doxytag: member="arm_math.h::arm_sqrt_f32" ref="ga56a40d1cf842b0b45267df6761975da0" args="(float32_t in, float32_t *pOut)" -->
 148 <div class="memitem">
 149 <div class="memproto">
 150       <table class="memname">
 151         <tr>
 152           <td class="memname">static __INLINE <a class="el" href="arm__math_8h.html#a5e459c6409dfcd2927bb8a57491d7cf6">arm_status</a> arm_sqrt_f32 </td>
 153           <td>(</td>
 154           <td class="paramtype"><a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a>&#160;</td>
 155           <td class="paramname"> <em>in</em>, </td>
 156         </tr>
 157         <tr>
 158           <td class="paramkey"></td>
 159           <td></td>
 160           <td class="paramtype"><a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> *&#160;</td>
 161           <td class="paramname"> <em>pOut</em>&#160;</td>
 162         </tr>
 163         <tr>
 164           <td></td>
 165           <td>)</td>
 166           <td></td><td><code> [static]</code></td>
 167         </tr>
 168       </table>
 169 </div>
 170 <div class="memdoc">
 171
 172 <p>Floating-point square root function. </p>
 173 <dl><dt><b>Parameters:</b></dt><dd>
 174   <table class="params">
 175     <tr><td class="paramdir">[in]</td><td class="paramname">in</td><td>input value. </td></tr>
 176     <tr><td class="paramdir">[out]</td><td class="paramname">*pOut</td><td>square root of input value. </td></tr>
 177   </table>
 178   </dd>
 179 </dl>
 180 <dl class="return"><dt><b>Returns:</b></dt><dd>The function returns ARM_MATH_SUCCESS if input value is positive value or ARM_MATH_ARGUMENT_ERROR if <code>in</code> is negative value and returns zero output for negative values. </dd></dl>
 181
 182 <p>Definition at line <a class="el" href="arm__math_8h_source.html#l05695">5695</a> of file <a class="el" href="arm__math_8h_source.html">arm_math.h</a>.</p>
 183
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