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diff --git a/devdocs/c/numeric%2Fmath%2Fsqrt.html b/devdocs/c/numeric%2Fmath%2Fsqrt.html new file mode 100644 index 00000000..460db07c --- /dev/null +++ b/devdocs/c/numeric%2Fmath%2Fsqrt.html @@ -0,0 +1,76 @@ + <h1 id="firstHeading" class="firstHeading">sqrt, sqrtf, sqrtl</h1> <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code><math.h></code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">float sqrtf( float arg );</pre> +</td> <td> (1) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> <tr class="t-dcl"> <td> <pre data-language="c">double sqrt( double arg );</pre> +</td> <td> (2) </td> <td class="t-dcl-nopad"> </td> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">long double sqrtl( long double arg );</pre> +</td> <td> (3) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> <tr class="t-dsc-header"> <th> Defined in header <code><tgmath.h></code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">#define sqrt( arg )</pre> +</td> <td> (4) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> </table> <div class="t-li1"> +<span class="t-li">1-3)</span> Computes square root of <code>arg</code>.</div> <div class="t-li1"> +<span class="t-li">4)</span> Type-generic macro: If <code>arg</code> has type <code>long double</code>, <code>sqrtl</code> is called. Otherwise, if <code>arg</code> has integer type or the type <code>double</code>, <code>sqrt</code> is called. Otherwise, <code>sqrtf</code> is called. If <code>arg</code> is complex or imaginary, then the macro invokes the corresponding complex function (<code><a href="http://en.cppreference.com/w/c/numeric/complex/csqrt"><span class="kw778">csqrtf</span></a></code>, <code><a href="http://en.cppreference.com/w/c/numeric/complex/csqrt"><span class="kw777">csqrt</span></a></code>, <code><a href="http://en.cppreference.com/w/c/numeric/complex/csqrt"><span class="kw779">csqrtl</span></a></code>).</div> <h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> arg </td> <td> - </td> <td> floating point value </td> +</tr> +</table> <h3 id="Return_value"> Return value</h3> <p>If no errors occur, square root of <code>arg</code> (\({\small \sqrt{arg} }\)<span class="t-mrad"><span>√</span><span>arg</span></span>), is returned.</p> +<p>If a domain error occurs, an implementation-defined value is returned (NaN where supported).</p> +<p>If a range error occurs due to underflow, the correct result (after rounding) is returned.</p> +<h3 id="Error_handling"> Error handling</h3> <p>Errors are reported as specified in <a href="math_errhandling" title="c/numeric/math/math errhandling"><code>math_errhandling</code></a>.</p> +<p>Domain error occurs if <code>arg</code> is less than zero.</p> +<p>If the implementation supports IEEE floating-point arithmetic (IEC 60559),</p> +<ul> +<li> If the argument is less than -0, <code><a href="../fenv/fe_exceptions" title="c/numeric/fenv/FE exceptions">FE_INVALID</a></code> is raised and NaN is returned. </li> +<li> If the argument is +∞ or ±0, it is returned, unmodified. </li> +<li> If the argument is NaN, NaN is returned </li> +</ul> <h3 id="Notes"> Notes</h3> <p><code>sqrt</code> is required by the IEEE standard to be correctly rounded from the infinitely precise result. In particular, the exact result is produced if it can be represented in the floating-point type. The only other operations which require this are the <a href="../../language/operator_arithmetic" title="c/language/operator arithmetic">arithmetic operators</a> and the function <code><a href="fma" title="c/numeric/math/fma">fma</a></code>. Other functions, including <code><a href="pow" title="c/numeric/math/pow">pow</a></code>, are not so constrained.</p> +<h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include <stdio.h> +#include <math.h> +#include <errno.h> +#include <fenv.h> + +#pragma STDC FENV_ACCESS ON + +int main(void) +{ + // normal use + printf("sqrt(100) = %f\n", sqrt(100)); + printf("sqrt(2) = %f\n", sqrt(2)); + printf("golden ratio = %f\n", (1+sqrt(5))/2); + // special values + printf("sqrt(-0) = %f\n", sqrt(-0.0)); + // error handling + errno = 0; feclearexcept(FE_ALL_EXCEPT); + printf("sqrt(-1.0) = %f\n", sqrt(-1)); + if(errno == EDOM) perror(" errno == EDOM"); + if(fetestexcept(FE_INVALID)) puts(" FE_INVALID was raised"); +}</pre></div> <p>Possible output:</p> +<div class="text source-text"><pre data-language="c">sqrt(100) = 10.000000 +sqrt(2) = 1.414214 +golden ratio = 1.618034 +sqrt(-0) = -0.000000 +sqrt(-1.0) = -nan + errno = EDOM: Numerical argument out of domain + FE_INVALID was raised</pre></div> </div> <h3 id="References"> References</h3> <ul> +<li> C11 standard (ISO/IEC 9899:2011): </li> +<ul> +<li> 7.12.7.5 The sqrt functions (p: 249) </li> +<li> 7.25 Type-generic math <tgmath.h> (p: 373-375) </li> +<li> F.10.4.5 The sqrt functions (p: 525) </li> +</ul> +<li> C99 standard (ISO/IEC 9899:1999): </li> +<ul> +<li> 7.12.7.5 The sqrt functions (p: 229-230) </li> +<li> 7.22 Type-generic math <tgmath.h> (p: 335-337) </li> +<li> F.9.4.5 The sqrt functions (p: 462) </li> +</ul> +<li> C89/C90 standard (ISO/IEC 9899:1990): </li> +<ul><li> 4.5.5.2 The sqrt function </li></ul> +</ul> <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="pow" title="c/numeric/math/pow"> <span class="t-lines"><span>pow</span><span>powf</span><span>powl</span></span></a></div> +<div><span class="t-lines"><span><span class="t-mark-rev t-since-c99">(C99)</span></span><span><span class="t-mark-rev t-since-c99">(C99)</span></span></span></div> </td> <td> computes a number raised to the given power (\(\small{x^y}\)x<sup>y</sup>) <br> <span class="t-mark">(function)</span> </td> +</tr> <tr class="t-dsc"> <td> <div><a href="cbrt" title="c/numeric/math/cbrt"> <span class="t-lines"><span>cbrt</span><span>cbrtf</span><span>cbrtl</span></span></a></div> +<div><span class="t-lines"><span><span class="t-mark-rev t-since-c99">(C99)</span></span><span><span class="t-mark-rev t-since-c99">(C99)</span></span><span><span class="t-mark-rev t-since-c99">(C99)</span></span></span></div> </td> <td> computes cube root (\(\small{\sqrt[3]{x} }\)<span class="t-mrad"><span>3</span><span>√</span><span>x</span></span>) <br> <span class="t-mark">(function)</span> </td> +</tr> <tr class="t-dsc"> <td> <div><a href="hypot" title="c/numeric/math/hypot"> <span class="t-lines"><span>hypot</span><span>hypotf</span><span>hypotl</span></span></a></div> +<div><span class="t-lines"><span><span class="t-mark-rev t-since-c99">(C99)</span></span><span><span class="t-mark-rev t-since-c99">(C99)</span></span><span><span class="t-mark-rev t-since-c99">(C99)</span></span></span></div> </td> <td> computes square root of the sum of the squares of two given numbers (\(\scriptsize{\sqrt{x^2+y^2} }\)<span class="t-mrad"><span>√</span><span>x<sup class="t-su">2</sup>+y<sup class="t-su">2</sup></span></span>) <br> <span class="t-mark">(function)</span> </td> +</tr> <tr class="t-dsc"> <td> <div><a href="../complex/csqrt" title="c/numeric/complex/csqrt"> <span class="t-lines"><span>csqrt</span><span>csqrtf</span><span>csqrtl</span></span></a></div> +<div><span class="t-lines"><span><span class="t-mark-rev t-since-c99">(C99)</span></span><span><span class="t-mark-rev t-since-c99">(C99)</span></span><span><span class="t-mark-rev t-since-c99">(C99)</span></span></span></div> </td> <td> computes the complex square root <br> <span class="t-mark">(function)</span> </td> +</tr> <tr class="t-dsc"> <td colspan="2"> <span><a href="https://en.cppreference.com/w/cpp/numeric/math/sqrt" title="cpp/numeric/math/sqrt">C++ documentation</a></span> for <code>sqrt</code> </td> +</tr> </table> <div class="_attribution"> + <p class="_attribution-p"> + © cppreference.com<br>Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.<br> + <a href="https://en.cppreference.com/w/c/numeric/math/sqrt" class="_attribution-link">https://en.cppreference.com/w/c/numeric/math/sqrt</a> + </p> +</div> |