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| <h1>Square Root<br/> |
| <small> |
| [<a class="el" href="group__group_fast_math.html">Fast Math Functions</a>]</small> |
| </h1> </div> |
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| <tr><td colspan="2"><h2><a name="func-members"></a> |
| Functions</h2></td></tr> |
| <tr><td class="memItemLeft" align="right" valign="top"><a class="el" href="arm__math_8h.html#a5e459c6409dfcd2927bb8a57491d7cf6">arm_status</a> </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> |
| <tr><td class="memItemLeft" align="right" valign="top"><a class="el" href="arm__math_8h.html#a5e459c6409dfcd2927bb8a57491d7cf6">arm_status</a> </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> |
| <tr><td class="memItemLeft" align="right" valign="top">static __INLINE <a class="el" href="arm__math_8h.html#a5e459c6409dfcd2927bb8a57491d7cf6">arm_status</a> </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> |
| </table> |
| <hr/><a name="_details"></a><h2>Detailed Description</h2> |
| <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> |
| <pre> |
| x1 = x0 - f(x0)/f'(x0) |
| </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> |
| <pre> |
| x0 = in/2 [initial guess] |
| x1 = 1/2 * ( x0 + in / x0) [each iteration] |
| </pre> <hr/><h2>Function Documentation</h2> |
| <a class="anchor" id="ga119e25831e141d734d7ef10636670058"></a><!-- doxytag: member="arm_sqrt_q31.c::arm_sqrt_q31" ref="ga119e25831e141d734d7ef10636670058" args="(q31_t in, q31_t *pOut)" --> |
| <div class="memitem"> |
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| <table class="memname"> |
| <tr> |
| <td class="memname"><a class="el" href="arm__math_8h.html#a5e459c6409dfcd2927bb8a57491d7cf6">arm_status</a> arm_sqrt_q31 </td> |
| <td>(</td> |
| <td class="paramtype"><a class="el" href="arm__math_8h.html#adc89a3547f5324b7b3b95adec3806bc0">q31_t</a> </td> |
| <td class="paramname"> <em>in</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> * </td> |
| <td class="paramname"> <em>pOut</em> </td> |
| </tr> |
| <tr> |
| <td></td> |
| <td>)</td> |
| <td></td><td></td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| |
| <p>Q31 square root function. </p> |
| <dl><dt><b>Parameters:</b></dt><dd> |
| <table class="params"> |
| <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> |
| <tr><td class="paramdir">[out]</td><td class="paramname">*pOut</td><td>square root of input value. </td></tr> |
| </table> |
| </dd> |
| </dl> |
| <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> |
| |
| <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> |
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| <a class="anchor" id="ga5abe5ca724f3e15849662b03752c1238"></a><!-- doxytag: member="arm_sqrt_q15.c::arm_sqrt_q15" ref="ga5abe5ca724f3e15849662b03752c1238" args="(q15_t in, q15_t *pOut)" --> |
| <div class="memitem"> |
| <div class="memproto"> |
| <table class="memname"> |
| <tr> |
| <td class="memname"><a class="el" href="arm__math_8h.html#a5e459c6409dfcd2927bb8a57491d7cf6">arm_status</a> arm_sqrt_q15 </td> |
| <td>(</td> |
| <td class="paramtype"><a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> </td> |
| <td class="paramname"> <em>in</em>, </td> |
| </tr> |
| <tr> |
| <td class="paramkey"></td> |
| <td></td> |
| <td class="paramtype"><a class="el" href="arm__math_8h.html#ab5a8fb21a5b3b983d5f54f31614052ea">q15_t</a> * </td> |
| <td class="paramname"> <em>pOut</em> </td> |
| </tr> |
| <tr> |
| <td></td> |
| <td>)</td> |
| <td></td><td></td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| |
| <p>Q15 square root function. </p> |
| <dl><dt><b>Parameters:</b></dt><dd> |
| <table class="params"> |
| <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> |
| <tr><td class="paramdir">[out]</td><td class="paramname">*pOut</td><td>square root of input value. </td></tr> |
| </table> |
| </dd> |
| </dl> |
| <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> |
| |
| <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> |
| |
| </div> |
| </div> |
| <a class="anchor" id="ga56a40d1cf842b0b45267df6761975da0"></a><!-- doxytag: member="arm_math.h::arm_sqrt_f32" ref="ga56a40d1cf842b0b45267df6761975da0" args="(float32_t in, float32_t *pOut)" --> |
| <div class="memitem"> |
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| <table class="memname"> |
| <tr> |
| <td class="memname">static __INLINE <a class="el" href="arm__math_8h.html#a5e459c6409dfcd2927bb8a57491d7cf6">arm_status</a> arm_sqrt_f32 </td> |
| <td>(</td> |
| <td class="paramtype"><a class="el" href="arm__math_8h.html#a4611b605e45ab401f02cab15c5e38715">float32_t</a> </td> |
| <td class="paramname"> <em>in</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> * </td> |
| <td class="paramname"> <em>pOut</em> </td> |
| </tr> |
| <tr> |
| <td></td> |
| <td>)</td> |
| <td></td><td><code> [static]</code></td> |
| </tr> |
| </table> |
| </div> |
| <div class="memdoc"> |
| |
| <p>Floating-point square root function. </p> |
| <dl><dt><b>Parameters:</b></dt><dd> |
| <table class="params"> |
| <tr><td class="paramdir">[in]</td><td class="paramname">in</td><td>input value. </td></tr> |
| <tr><td class="paramdir">[out]</td><td class="paramname">*pOut</td><td>square root of input value. </td></tr> |
| </table> |
| </dd> |
| </dl> |
| <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> |
| |
| <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> |
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