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diff --git a/devdocs/c/numeric%2Fmath%2Fnextafter.html b/devdocs/c/numeric%2Fmath%2Fnextafter.html deleted file mode 100644 index ad038edc..00000000 --- a/devdocs/c/numeric%2Fmath%2Fnextafter.html +++ /dev/null @@ -1,109 +0,0 @@ - <h1 id="firstHeading" class="firstHeading">nextafter, nextafterf, nextafterl, nexttoward, nexttowardf, nexttowardl</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 nextafterf( float from, float to );</pre> -</td> <td> (1) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">double nextafter( double from, double to );</pre> -</td> <td> (2) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">long double nextafterl( long double from, long double to );</pre> -</td> <td> (3) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">float nexttowardf( float from, long double to );</pre> -</td> <td> (4) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">double nexttoward( double from, long double to );</pre> -</td> <td> (5) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">long double nexttowardl( long double from, long double to );</pre> -</td> <td> (6) </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 nextafter(from, to)</pre> -</td> <td> (7) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">#define nexttoward(from, to)</pre> -</td> <td> (8) </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> First, converts both arguments to the type of the function, then returns the next representable value of <code>from</code> in the direction of <code>to</code>. If <code>from</code> equals to <code>to</code>, <code>to</code> is returned.</div> <div class="t-li1"> -<span class="t-li">4-6)</span> First, converts the first argument to the type of the function, then returns the next representable value of <code>from</code> in the direction of <code>to</code>. If <code>from</code> equals to <code>to</code>, <code>to</code> is returned, converted from <code>long double</code> to the return type of the function without loss of range or precision.</div> <div class="t-li1"> -<span class="t-li">7)</span> Type-generic macro: If any argument has type <code>long double</code>, <code>nextafterl</code> is called. Otherwise, if any argument has integer type or has type <code>double</code>, <code>nextafter</code> is called. Otherwise, <code>nextafterf</code> is called.</div> <div class="t-li1"> -<span class="t-li">8)</span> Type-generic macro: If the argument <code>from</code> has type <code>long double</code>, <code>nexttowardl</code> is called. Otherwise, if <code>from</code> has integer type or the type <code>double</code>, <code>nexttoward</code> is called. Otherwise, <code>nexttowardf</code> is called.</div> <h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> from, to </td> <td> - </td> <td> floating point values </td> -</tr> -</table> <h3 id="Return_value"> Return value</h3> <p>If no errors occur, the next representable value of <code>from</code> in the direction of <code>to</code>. is returned. If <code>from</code> equals <code>to</code>, then <code>to</code> is returned, converted to the type of the function.</p> -<p>If a range error due to overflow occurs, <code><a href="huge_val" title="c/numeric/math/HUGE VAL">±HUGE_VAL</a></code>, <code>±HUGE_VALF</code>, or <code>±HUGE_VALL</code> is returned (with the same sign as <code>from</code>).</p> -<p>If a range error occurs due to underflow, the correct result 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>If the implementation supports IEEE floating-point arithmetic (IEC 60559),</p> -<ul> -<li> if <code>from</code> is finite, but the expected result is an infinity, raises <code><a href="../fenv/fe_exceptions" title="c/numeric/fenv/FE exceptions">FE_INEXACT</a></code> and <code><a href="../fenv/fe_exceptions" title="c/numeric/fenv/FE exceptions">FE_OVERFLOW</a></code> </li> -<li> if <code>from</code> does not equal <code>to</code> and the result is subnormal or zero, raises <code><a href="../fenv/fe_exceptions" title="c/numeric/fenv/FE exceptions">FE_INEXACT</a></code> and <code><a href="../fenv/fe_exceptions" title="c/numeric/fenv/FE exceptions">FE_UNDERFLOW</a></code> </li> -<li> in any case, the returned value is independent of the current rounding mode </li> -<li> if either <code>from</code> or <code>to</code> is NaN, NaN is returned </li> -</ul> <h3 id="Notes"> Notes</h3> <p><a rel="nofollow" class="external text" href="http://pubs.opengroup.org/onlinepubs/9699919799/functions/nextafter.html">POSIX specifies</a> that the overflow and the underflow conditions are range errors (<code><a href="../../error/errno" title="c/error/errno">errno</a></code> may be set).</p> -<p>IEC 60559 recommends that <code>from</code> is returned whenever <code>from == to</code>. These functions return <code>to</code> instead, which makes the behavior around zero consistent: <code>nextafter(-0.0, +0.0)</code> returns <code>+0.0</code> and <code>nextafter(+0.0, -0.0)</code> returns <code>-0.0</code>.</p> -<p><code>nextafter</code> is typically implemented by manipulation of IEEE representation (<a rel="nofollow" class="external text" href="https://github.com/bminor/glibc/blob/master/math/s_nextafter.c">glibc</a> <a rel="nofollow" class="external text" href="https://github.com/ifduyue/musl/blob/master/src/math/nextafter.c">musl</a>).</p> -<h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include <math.h> -#include <stdio.h> -#include <float.h> -#include <fenv.h> - -int main(void) -{ - float from1 = 0, to1 = nextafterf(from1, 1); - printf("The next representable float after %.2f is %.20g (%a)\n", from1, to1, to1); - - float from2 = 1, to2 = nextafterf(from2, 2); - printf("The next representable float after %.2f is %.20f (%a)\n", from2, to2, to2); - - double from3 = nextafter(0.1, 0), to3 = 0.1; - printf("The number 0.1 lies between two valid doubles:\n" - " %.56f (%a)\nand %.55f (%a)\n", from3, from3, to3, to3); - - // difference between nextafter and nexttoward: - long double dir = nextafterl(from1, 1); // first subnormal long double - float x = nextafterf(from1, dir); // first converts dir to float, giving 0 - printf("Using nextafter, next float after %.2f (%a) is %.20g (%a)\n", - from1, from1, x, x); - x = nexttowardf(from1, dir); - printf("Using nexttoward, next float after %.2f (%a) is %.20g (%a)\n", - from1, from1, x, x); - - // special values - { - #pragma STDC FENV_ACCESS ON - feclearexcept(FE_ALL_EXCEPT); - double from4 = DBL_MAX, to4 = nextafter(from4, INFINITY); - printf("The next representable double after %.2g (%a) is %.23f (%a)\n", - from4, from4, to4, to4); - if(fetestexcept(FE_OVERFLOW)) puts(" raised FE_OVERFLOW"); - if(fetestexcept(FE_INEXACT)) puts(" raised FE_INEXACT"); - } // end FENV_ACCESS block - - float from5 = 0.0, to5 = nextafter(from5, -0.0); - printf("nextafter(+0.0, -0.0) gives %.2g (%a)\n", to5, to5); -}</pre></div> <p>Output:</p> -<div class="text source-text"><pre data-language="c">The next representable float after 0.00 is 1.4012984643248170709e-45 (0x1p-149) -The next representable float after 1.00 is 1.00000011920928955078 (0x1.000002p+0) -The number 0.1 lies between two valid doubles: - 0.09999999999999999167332731531132594682276248931884765625 (0x1.9999999999999p-4) -and 0.1000000000000000055511151231257827021181583404541015625 (0x1.999999999999ap-4) -Using nextafter, next float after 0.00 (0x0p+0) is 0 (0x0p+0) -Using nexttoward, next float after 0.00 (0x0p+0) is 1.4012984643248170709e-45 (0x1p-149) -The next representable double after 1.8e+308 (0x1.fffffffffffffp+1023) is inf (inf) - raised FE_OVERFLOW - raised FE_INEXACT -nextafter(+0.0, -0.0) gives -0 (-0x0p+0)</pre></div> </div> <h3 id="References"> References</h3> <ul> -<li> C17 standard (ISO/IEC 9899:2018): </li> -<ul> -<li> 7.12.11.3 The nextafter functions (p: 187) </li> -<li> 7.12.11.4 The nexttoward functions (p: 187) </li> -<li> 7.25 Type-generic math <tgmath.h> (p: 272-273) </li> -<li> F.10.8.3 The nextafter functions (p: 386) </li> -<li> F.10.8.4 The nexttoward functions (p: 386) </li> -</ul> -<li> C11 standard (ISO/IEC 9899:2011): </li> -<ul> -<li> 7.12.11.3 The nextafter functions (p: 256) </li> -<li> 7.12.11.4 The nexttoward functions (p: 257) </li> -<li> 7.25 Type-generic math <tgmath.h> (p: 373-375) </li> -<li> F.10.8.3 The nextafter functions (p: 529) </li> -<li> F.10.8.4 The nexttoward functions (p: 529) </li> -</ul> -<li> C99 standard (ISO/IEC 9899:1999): </li> -<ul> -<li> 7.12.11.3 The nextafter functions (p: 237) </li> -<li> 7.12.11.4 The nexttoward functions (p: 238) </li> -<li> 7.22 Type-generic math <tgmath.h> (p: 335-337) </li> -<li> F.9.8.3 The nextafter functions (p: 466) </li> -<li> F.9.8.4 The nexttoward functions (p: 466) </li> -</ul> -</ul> <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td colspan="2"> <span><a href="https://en.cppreference.com/w/cpp/numeric/math/nextafter" title="cpp/numeric/math/nextafter">C++ documentation</a></span> for <code>nextafter</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/nextafter" class="_attribution-link">https://en.cppreference.com/w/c/numeric/math/nextafter</a> - </p> -</div> |