| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `/root/.cargo/registry/src/github.com-1ecc6299db9ec823/libm-0.2.7/src/math/j1f.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>j1f.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../../normalize.css"><link rel="stylesheet" href="../../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../../ayu.css" disabled><link rel="stylesheet" href="../../../dark.css" disabled><link rel="stylesheet" href="../../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../../storage.js"></script><script defer src="../../../source-script.js"></script><script defer src="../../../source-files.js"></script><script defer src="../../../main.js"></script><noscript><link rel="stylesheet" href="../../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../../favicon.svg"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../../libm/index.html"><div class="logo-container"><img class="rust-logo" src="../../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../../libm/index.html"><img class="rust-logo" src="../../../rust-logo.svg" alt="logo"></a><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
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| </pre><pre class="rust"><code><span class="comment">/* origin: FreeBSD /usr/src/lib/msun/src/e_j1f.c */ |
| /* |
| * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. |
| */ |
| /* |
| * ==================================================== |
| * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
| * |
| * Developed at SunPro, a Sun Microsystems, Inc. business. |
| * Permission to use, copy, modify, and distribute this |
| * software is freely granted, provided that this notice |
| * is preserved. |
| * ==================================================== |
| */ |
| |
| </span><span class="kw">use super</span>::{cosf, fabsf, logf, sinf, sqrtf}; |
| |
| <span class="kw">const </span>INVSQRTPI: f32 = <span class="number">5.6418961287e-01</span>; <span class="comment">/* 0x3f106ebb */ |
| </span><span class="kw">const </span>TPI: f32 = <span class="number">6.3661974669e-01</span>; <span class="comment">/* 0x3f22f983 */ |
| |
| </span><span class="kw">fn </span>common(ix: u32, x: f32, y1: bool, sign: bool) -> f32 { |
| <span class="kw">let </span>z: f64; |
| <span class="kw">let </span><span class="kw-2">mut </span>s: f64; |
| <span class="kw">let </span>c: f64; |
| <span class="kw">let </span><span class="kw-2">mut </span>ss: f64; |
| <span class="kw">let </span><span class="kw-2">mut </span>cc: f64; |
| |
| s = sinf(x) <span class="kw">as </span>f64; |
| <span class="kw">if </span>y1 { |
| s = -s; |
| } |
| c = cosf(x) <span class="kw">as </span>f64; |
| cc = s - c; |
| <span class="kw">if </span>ix < <span class="number">0x7f000000 </span>{ |
| ss = -s - c; |
| z = cosf(<span class="number">2.0 </span>* x) <span class="kw">as </span>f64; |
| <span class="kw">if </span>s * c > <span class="number">0.0 </span>{ |
| cc = z / ss; |
| } <span class="kw">else </span>{ |
| ss = z / cc; |
| } |
| <span class="kw">if </span>ix < <span class="number">0x58800000 </span>{ |
| <span class="kw">if </span>y1 { |
| ss = -ss; |
| } |
| cc = (ponef(x) <span class="kw">as </span>f64) * cc - (qonef(x) <span class="kw">as </span>f64) * ss; |
| } |
| } |
| <span class="kw">if </span>sign { |
| cc = -cc; |
| } |
| <span class="kw">return </span>(((INVSQRTPI <span class="kw">as </span>f64) * cc) / (sqrtf(x) <span class="kw">as </span>f64)) <span class="kw">as </span>f32; |
| } |
| |
| <span class="comment">/* R0/S0 on [0,2] */ |
| </span><span class="kw">const </span>R00: f32 = -<span class="number">6.2500000000e-02</span>; <span class="comment">/* 0xbd800000 */ |
| </span><span class="kw">const </span>R01: f32 = <span class="number">1.4070566976e-03</span>; <span class="comment">/* 0x3ab86cfd */ |
| </span><span class="kw">const </span>R02: f32 = -<span class="number">1.5995563444e-05</span>; <span class="comment">/* 0xb7862e36 */ |
| </span><span class="kw">const </span>R03: f32 = <span class="number">4.9672799207e-08</span>; <span class="comment">/* 0x335557d2 */ |
| </span><span class="kw">const </span>S01: f32 = <span class="number">1.9153760746e-02</span>; <span class="comment">/* 0x3c9ce859 */ |
| </span><span class="kw">const </span>S02: f32 = <span class="number">1.8594678841e-04</span>; <span class="comment">/* 0x3942fab6 */ |
| </span><span class="kw">const </span>S03: f32 = <span class="number">1.1771846857e-06</span>; <span class="comment">/* 0x359dffc2 */ |
| </span><span class="kw">const </span>S04: f32 = <span class="number">5.0463624390e-09</span>; <span class="comment">/* 0x31ad6446 */ |
| </span><span class="kw">const </span>S05: f32 = <span class="number">1.2354227016e-11</span>; <span class="comment">/* 0x2d59567e */ |
| |
| </span><span class="kw">pub fn </span>j1f(x: f32) -> f32 { |
| <span class="kw">let </span><span class="kw-2">mut </span>z: f32; |
| <span class="kw">let </span>r: f32; |
| <span class="kw">let </span>s: f32; |
| <span class="kw">let </span><span class="kw-2">mut </span>ix: u32; |
| <span class="kw">let </span>sign: bool; |
| |
| ix = x.to_bits(); |
| sign = (ix >> <span class="number">31</span>) != <span class="number">0</span>; |
| ix &= <span class="number">0x7fffffff</span>; |
| <span class="kw">if </span>ix >= <span class="number">0x7f800000 </span>{ |
| <span class="kw">return </span><span class="number">1.0 </span>/ (x * x); |
| } |
| <span class="kw">if </span>ix >= <span class="number">0x40000000 </span>{ |
| <span class="comment">/* |x| >= 2 */ |
| </span><span class="kw">return </span>common(ix, fabsf(x), <span class="bool-val">false</span>, sign); |
| } |
| <span class="kw">if </span>ix >= <span class="number">0x39000000 </span>{ |
| <span class="comment">/* |x| >= 2**-13 */ |
| </span>z = x * x; |
| r = z * (R00 + z * (R01 + z * (R02 + z * R03))); |
| s = <span class="number">1.0 </span>+ z * (S01 + z * (S02 + z * (S03 + z * (S04 + z * S05)))); |
| z = <span class="number">0.5 </span>+ r / s; |
| } <span class="kw">else </span>{ |
| z = <span class="number">0.5</span>; |
| } |
| <span class="kw">return </span>z * x; |
| } |
| |
| <span class="kw">const </span>U0: [f32; <span class="number">5</span>] = [ |
| -<span class="number">1.9605709612e-01</span>, <span class="comment">/* 0xbe48c331 */ |
| </span><span class="number">5.0443872809e-02</span>, <span class="comment">/* 0x3d4e9e3c */ |
| </span>-<span class="number">1.9125689287e-03</span>, <span class="comment">/* 0xbafaaf2a */ |
| </span><span class="number">2.3525259166e-05</span>, <span class="comment">/* 0x37c5581c */ |
| </span>-<span class="number">9.1909917899e-08</span>, <span class="comment">/* 0xb3c56003 */ |
| </span>]; |
| <span class="kw">const </span>V0: [f32; <span class="number">5</span>] = [ |
| <span class="number">1.9916731864e-02</span>, <span class="comment">/* 0x3ca3286a */ |
| </span><span class="number">2.0255257550e-04</span>, <span class="comment">/* 0x3954644b */ |
| </span><span class="number">1.3560879779e-06</span>, <span class="comment">/* 0x35b602d4 */ |
| </span><span class="number">6.2274145840e-09</span>, <span class="comment">/* 0x31d5f8eb */ |
| </span><span class="number">1.6655924903e-11</span>, <span class="comment">/* 0x2d9281cf */ |
| </span>]; |
| |
| <span class="kw">pub fn </span>y1f(x: f32) -> f32 { |
| <span class="kw">let </span>z: f32; |
| <span class="kw">let </span>u: f32; |
| <span class="kw">let </span>v: f32; |
| <span class="kw">let </span>ix: u32; |
| |
| ix = x.to_bits(); |
| <span class="kw">if </span>(ix & <span class="number">0x7fffffff</span>) == <span class="number">0 </span>{ |
| <span class="kw">return </span>-<span class="number">1.0 </span>/ <span class="number">0.0</span>; |
| } |
| <span class="kw">if </span>(ix >> <span class="number">31</span>) != <span class="number">0 </span>{ |
| <span class="kw">return </span><span class="number">0.0 </span>/ <span class="number">0.0</span>; |
| } |
| <span class="kw">if </span>ix >= <span class="number">0x7f800000 </span>{ |
| <span class="kw">return </span><span class="number">1.0 </span>/ x; |
| } |
| <span class="kw">if </span>ix >= <span class="number">0x40000000 </span>{ |
| <span class="comment">/* |x| >= 2.0 */ |
| </span><span class="kw">return </span>common(ix, x, <span class="bool-val">true</span>, <span class="bool-val">false</span>); |
| } |
| <span class="kw">if </span>ix < <span class="number">0x33000000 </span>{ |
| <span class="comment">/* x < 2**-25 */ |
| </span><span class="kw">return </span>-TPI / x; |
| } |
| z = x * x; |
| u = U0[<span class="number">0</span>] + z * (U0[<span class="number">1</span>] + z * (U0[<span class="number">2</span>] + z * (U0[<span class="number">3</span>] + z * U0[<span class="number">4</span>]))); |
| v = <span class="number">1.0 </span>+ z * (V0[<span class="number">0</span>] + z * (V0[<span class="number">1</span>] + z * (V0[<span class="number">2</span>] + z * (V0[<span class="number">3</span>] + z * V0[<span class="number">4</span>])))); |
| <span class="kw">return </span>x * (u / v) + TPI * (j1f(x) * logf(x) - <span class="number">1.0 </span>/ x); |
| } |
| |
| <span class="comment">/* For x >= 8, the asymptotic expansions of pone is |
| * 1 + 15/128 s^2 - 4725/2^15 s^4 - ..., where s = 1/x. |
| * We approximate pone by |
| * pone(x) = 1 + (R/S) |
| * where R = pr0 + pr1*s^2 + pr2*s^4 + ... + pr5*s^10 |
| * S = 1 + ps0*s^2 + ... + ps4*s^10 |
| * and |
| * | pone(x)-1-R/S | <= 2 ** ( -60.06) |
| */ |
| |
| </span><span class="kw">const </span>PR8: [f32; <span class="number">6</span>] = [ |
| <span class="comment">/* for x in [inf, 8]=1/[0,0.125] */ |
| </span><span class="number">0.0000000000e+00</span>, <span class="comment">/* 0x00000000 */ |
| </span><span class="number">1.1718750000e-01</span>, <span class="comment">/* 0x3df00000 */ |
| </span><span class="number">1.3239480972e+01</span>, <span class="comment">/* 0x4153d4ea */ |
| </span><span class="number">4.1205184937e+02</span>, <span class="comment">/* 0x43ce06a3 */ |
| </span><span class="number">3.8747453613e+03</span>, <span class="comment">/* 0x45722bed */ |
| </span><span class="number">7.9144794922e+03</span>, <span class="comment">/* 0x45f753d6 */ |
| </span>]; |
| <span class="kw">const </span>PS8: [f32; <span class="number">5</span>] = [ |
| <span class="number">1.1420736694e+02</span>, <span class="comment">/* 0x42e46a2c */ |
| </span><span class="number">3.6509309082e+03</span>, <span class="comment">/* 0x45642ee5 */ |
| </span><span class="number">3.6956207031e+04</span>, <span class="comment">/* 0x47105c35 */ |
| </span><span class="number">9.7602796875e+04</span>, <span class="comment">/* 0x47bea166 */ |
| </span><span class="number">3.0804271484e+04</span>, <span class="comment">/* 0x46f0a88b */ |
| </span>]; |
| |
| <span class="kw">const </span>PR5: [f32; <span class="number">6</span>] = [ |
| <span class="comment">/* for x in [8,4.5454]=1/[0.125,0.22001] */ |
| </span><span class="number">1.3199052094e-11</span>, <span class="comment">/* 0x2d68333f */ |
| </span><span class="number">1.1718749255e-01</span>, <span class="comment">/* 0x3defffff */ |
| </span><span class="number">6.8027510643e+00</span>, <span class="comment">/* 0x40d9b023 */ |
| </span><span class="number">1.0830818176e+02</span>, <span class="comment">/* 0x42d89dca */ |
| </span><span class="number">5.1763616943e+02</span>, <span class="comment">/* 0x440168b7 */ |
| </span><span class="number">5.2871520996e+02</span>, <span class="comment">/* 0x44042dc6 */ |
| </span>]; |
| <span class="kw">const </span>PS5: [f32; <span class="number">5</span>] = [ |
| <span class="number">5.9280597687e+01</span>, <span class="comment">/* 0x426d1f55 */ |
| </span><span class="number">9.9140142822e+02</span>, <span class="comment">/* 0x4477d9b1 */ |
| </span><span class="number">5.3532670898e+03</span>, <span class="comment">/* 0x45a74a23 */ |
| </span><span class="number">7.8446904297e+03</span>, <span class="comment">/* 0x45f52586 */ |
| </span><span class="number">1.5040468750e+03</span>, <span class="comment">/* 0x44bc0180 */ |
| </span>]; |
| |
| <span class="kw">const </span>PR3: [f32; <span class="number">6</span>] = [ |
| <span class="number">3.0250391081e-09</span>, <span class="comment">/* 0x314fe10d */ |
| </span><span class="number">1.1718686670e-01</span>, <span class="comment">/* 0x3defffab */ |
| </span><span class="number">3.9329774380e+00</span>, <span class="comment">/* 0x407bb5e7 */ |
| </span><span class="number">3.5119403839e+01</span>, <span class="comment">/* 0x420c7a45 */ |
| </span><span class="number">9.1055007935e+01</span>, <span class="comment">/* 0x42b61c2a */ |
| </span><span class="number">4.8559066772e+01</span>, <span class="comment">/* 0x42423c7c */ |
| </span>]; |
| <span class="kw">const </span>PS3: [f32; <span class="number">5</span>] = [ |
| <span class="number">3.4791309357e+01</span>, <span class="comment">/* 0x420b2a4d */ |
| </span><span class="number">3.3676245117e+02</span>, <span class="comment">/* 0x43a86198 */ |
| </span><span class="number">1.0468714600e+03</span>, <span class="comment">/* 0x4482dbe3 */ |
| </span><span class="number">8.9081134033e+02</span>, <span class="comment">/* 0x445eb3ed */ |
| </span><span class="number">1.0378793335e+02</span>, <span class="comment">/* 0x42cf936c */ |
| </span>]; |
| |
| <span class="kw">const </span>PR2: [f32; <span class="number">6</span>] = [ |
| <span class="comment">/* for x in [2.8570,2]=1/[0.3499,0.5] */ |
| </span><span class="number">1.0771083225e-07</span>, <span class="comment">/* 0x33e74ea8 */ |
| </span><span class="number">1.1717621982e-01</span>, <span class="comment">/* 0x3deffa16 */ |
| </span><span class="number">2.3685150146e+00</span>, <span class="comment">/* 0x401795c0 */ |
| </span><span class="number">1.2242610931e+01</span>, <span class="comment">/* 0x4143e1bc */ |
| </span><span class="number">1.7693971634e+01</span>, <span class="comment">/* 0x418d8d41 */ |
| </span><span class="number">5.0735230446e+00</span>, <span class="comment">/* 0x40a25a4d */ |
| </span>]; |
| <span class="kw">const </span>PS2: [f32; <span class="number">5</span>] = [ |
| <span class="number">2.1436485291e+01</span>, <span class="comment">/* 0x41ab7dec */ |
| </span><span class="number">1.2529022980e+02</span>, <span class="comment">/* 0x42fa9499 */ |
| </span><span class="number">2.3227647400e+02</span>, <span class="comment">/* 0x436846c7 */ |
| </span><span class="number">1.1767937469e+02</span>, <span class="comment">/* 0x42eb5bd7 */ |
| </span><span class="number">8.3646392822e+00</span>, <span class="comment">/* 0x4105d590 */ |
| </span>]; |
| |
| <span class="kw">fn </span>ponef(x: f32) -> f32 { |
| <span class="kw">let </span>p: <span class="kw-2">&</span>[f32; <span class="number">6</span>]; |
| <span class="kw">let </span>q: <span class="kw-2">&</span>[f32; <span class="number">5</span>]; |
| <span class="kw">let </span>z: f32; |
| <span class="kw">let </span>r: f32; |
| <span class="kw">let </span>s: f32; |
| <span class="kw">let </span><span class="kw-2">mut </span>ix: u32; |
| |
| ix = x.to_bits(); |
| ix &= <span class="number">0x7fffffff</span>; |
| <span class="kw">if </span>ix >= <span class="number">0x41000000 </span>{ |
| p = <span class="kw-2">&</span>PR8; |
| q = <span class="kw-2">&</span>PS8; |
| } <span class="kw">else if </span>ix >= <span class="number">0x409173eb </span>{ |
| p = <span class="kw-2">&</span>PR5; |
| q = <span class="kw-2">&</span>PS5; |
| } <span class="kw">else if </span>ix >= <span class="number">0x4036d917 </span>{ |
| p = <span class="kw-2">&</span>PR3; |
| q = <span class="kw-2">&</span>PS3; |
| } <span class="kw">else |
| </span><span class="comment">/*ix >= 0x40000000*/ |
| </span>{ |
| p = <span class="kw-2">&</span>PR2; |
| q = <span class="kw-2">&</span>PS2; |
| } |
| z = <span class="number">1.0 </span>/ (x * x); |
| r = p[<span class="number">0</span>] + z * (p[<span class="number">1</span>] + z * (p[<span class="number">2</span>] + z * (p[<span class="number">3</span>] + z * (p[<span class="number">4</span>] + z * p[<span class="number">5</span>])))); |
| s = <span class="number">1.0 </span>+ z * (q[<span class="number">0</span>] + z * (q[<span class="number">1</span>] + z * (q[<span class="number">2</span>] + z * (q[<span class="number">3</span>] + z * q[<span class="number">4</span>])))); |
| <span class="kw">return </span><span class="number">1.0 </span>+ r / s; |
| } |
| |
| <span class="comment">/* For x >= 8, the asymptotic expansions of qone is |
| * 3/8 s - 105/1024 s^3 - ..., where s = 1/x. |
| * We approximate pone by |
| * qone(x) = s*(0.375 + (R/S)) |
| * where R = qr1*s^2 + qr2*s^4 + ... + qr5*s^10 |
| * S = 1 + qs1*s^2 + ... + qs6*s^12 |
| * and |
| * | qone(x)/s -0.375-R/S | <= 2 ** ( -61.13) |
| */ |
| |
| </span><span class="kw">const </span>QR8: [f32; <span class="number">6</span>] = [ |
| <span class="comment">/* for x in [inf, 8]=1/[0,0.125] */ |
| </span><span class="number">0.0000000000e+00</span>, <span class="comment">/* 0x00000000 */ |
| </span>-<span class="number">1.0253906250e-01</span>, <span class="comment">/* 0xbdd20000 */ |
| </span>-<span class="number">1.6271753311e+01</span>, <span class="comment">/* 0xc1822c8d */ |
| </span>-<span class="number">7.5960174561e+02</span>, <span class="comment">/* 0xc43de683 */ |
| </span>-<span class="number">1.1849806641e+04</span>, <span class="comment">/* 0xc639273a */ |
| </span>-<span class="number">4.8438511719e+04</span>, <span class="comment">/* 0xc73d3683 */ |
| </span>]; |
| <span class="kw">const </span>QS8: [f32; <span class="number">6</span>] = [ |
| <span class="number">1.6139537048e+02</span>, <span class="comment">/* 0x43216537 */ |
| </span><span class="number">7.8253862305e+03</span>, <span class="comment">/* 0x45f48b17 */ |
| </span><span class="number">1.3387534375e+05</span>, <span class="comment">/* 0x4802bcd6 */ |
| </span><span class="number">7.1965775000e+05</span>, <span class="comment">/* 0x492fb29c */ |
| </span><span class="number">6.6660125000e+05</span>, <span class="comment">/* 0x4922be94 */ |
| </span>-<span class="number">2.9449025000e+05</span>, <span class="comment">/* 0xc88fcb48 */ |
| </span>]; |
| |
| <span class="kw">const </span>QR5: [f32; <span class="number">6</span>] = [ |
| <span class="comment">/* for x in [8,4.5454]=1/[0.125,0.22001] */ |
| </span>-<span class="number">2.0897993405e-11</span>, <span class="comment">/* 0xadb7d219 */ |
| </span>-<span class="number">1.0253904760e-01</span>, <span class="comment">/* 0xbdd1fffe */ |
| </span>-<span class="number">8.0564479828e+00</span>, <span class="comment">/* 0xc100e736 */ |
| </span>-<span class="number">1.8366960144e+02</span>, <span class="comment">/* 0xc337ab6b */ |
| </span>-<span class="number">1.3731937256e+03</span>, <span class="comment">/* 0xc4aba633 */ |
| </span>-<span class="number">2.6124443359e+03</span>, <span class="comment">/* 0xc523471c */ |
| </span>]; |
| <span class="kw">const </span>QS5: [f32; <span class="number">6</span>] = [ |
| <span class="number">8.1276550293e+01</span>, <span class="comment">/* 0x42a28d98 */ |
| </span><span class="number">1.9917987061e+03</span>, <span class="comment">/* 0x44f8f98f */ |
| </span><span class="number">1.7468484375e+04</span>, <span class="comment">/* 0x468878f8 */ |
| </span><span class="number">4.9851425781e+04</span>, <span class="comment">/* 0x4742bb6d */ |
| </span><span class="number">2.7948074219e+04</span>, <span class="comment">/* 0x46da5826 */ |
| </span>-<span class="number">4.7191835938e+03</span>, <span class="comment">/* 0xc5937978 */ |
| </span>]; |
| |
| <span class="kw">const </span>QR3: [f32; <span class="number">6</span>] = [ |
| -<span class="number">5.0783124372e-09</span>, <span class="comment">/* 0xb1ae7d4f */ |
| </span>-<span class="number">1.0253783315e-01</span>, <span class="comment">/* 0xbdd1ff5b */ |
| </span>-<span class="number">4.6101160049e+00</span>, <span class="comment">/* 0xc0938612 */ |
| </span>-<span class="number">5.7847221375e+01</span>, <span class="comment">/* 0xc267638e */ |
| </span>-<span class="number">2.2824453735e+02</span>, <span class="comment">/* 0xc3643e9a */ |
| </span>-<span class="number">2.1921012878e+02</span>, <span class="comment">/* 0xc35b35cb */ |
| </span>]; |
| <span class="kw">const </span>QS3: [f32; <span class="number">6</span>] = [ |
| <span class="number">4.7665153503e+01</span>, <span class="comment">/* 0x423ea91e */ |
| </span><span class="number">6.7386511230e+02</span>, <span class="comment">/* 0x4428775e */ |
| </span><span class="number">3.3801528320e+03</span>, <span class="comment">/* 0x45534272 */ |
| </span><span class="number">5.5477290039e+03</span>, <span class="comment">/* 0x45ad5dd5 */ |
| </span><span class="number">1.9031191406e+03</span>, <span class="comment">/* 0x44ede3d0 */ |
| </span>-<span class="number">1.3520118713e+02</span>, <span class="comment">/* 0xc3073381 */ |
| </span>]; |
| |
| <span class="kw">const </span>QR2: [f32; <span class="number">6</span>] = [ |
| <span class="comment">/* for x in [2.8570,2]=1/[0.3499,0.5] */ |
| </span>-<span class="number">1.7838172539e-07</span>, <span class="comment">/* 0xb43f8932 */ |
| </span>-<span class="number">1.0251704603e-01</span>, <span class="comment">/* 0xbdd1f475 */ |
| </span>-<span class="number">2.7522056103e+00</span>, <span class="comment">/* 0xc0302423 */ |
| </span>-<span class="number">1.9663616180e+01</span>, <span class="comment">/* 0xc19d4f16 */ |
| </span>-<span class="number">4.2325313568e+01</span>, <span class="comment">/* 0xc2294d1f */ |
| </span>-<span class="number">2.1371921539e+01</span>, <span class="comment">/* 0xc1aaf9b2 */ |
| </span>]; |
| <span class="kw">const </span>QS2: [f32; <span class="number">6</span>] = [ |
| <span class="number">2.9533363342e+01</span>, <span class="comment">/* 0x41ec4454 */ |
| </span><span class="number">2.5298155212e+02</span>, <span class="comment">/* 0x437cfb47 */ |
| </span><span class="number">7.5750280762e+02</span>, <span class="comment">/* 0x443d602e */ |
| </span><span class="number">7.3939318848e+02</span>, <span class="comment">/* 0x4438d92a */ |
| </span><span class="number">1.5594900513e+02</span>, <span class="comment">/* 0x431bf2f2 */ |
| </span>-<span class="number">4.9594988823e+00</span>, <span class="comment">/* 0xc09eb437 */ |
| </span>]; |
| |
| <span class="kw">fn </span>qonef(x: f32) -> f32 { |
| <span class="kw">let </span>p: <span class="kw-2">&</span>[f32; <span class="number">6</span>]; |
| <span class="kw">let </span>q: <span class="kw-2">&</span>[f32; <span class="number">6</span>]; |
| <span class="kw">let </span>s: f32; |
| <span class="kw">let </span>r: f32; |
| <span class="kw">let </span>z: f32; |
| <span class="kw">let </span><span class="kw-2">mut </span>ix: u32; |
| |
| ix = x.to_bits(); |
| ix &= <span class="number">0x7fffffff</span>; |
| <span class="kw">if </span>ix >= <span class="number">0x41000000 </span>{ |
| p = <span class="kw-2">&</span>QR8; |
| q = <span class="kw-2">&</span>QS8; |
| } <span class="kw">else if </span>ix >= <span class="number">0x409173eb </span>{ |
| p = <span class="kw-2">&</span>QR5; |
| q = <span class="kw-2">&</span>QS5; |
| } <span class="kw">else if </span>ix >= <span class="number">0x4036d917 </span>{ |
| p = <span class="kw-2">&</span>QR3; |
| q = <span class="kw-2">&</span>QS3; |
| } <span class="kw">else |
| </span><span class="comment">/*ix >= 0x40000000*/ |
| </span>{ |
| p = <span class="kw-2">&</span>QR2; |
| q = <span class="kw-2">&</span>QS2; |
| } |
| z = <span class="number">1.0 </span>/ (x * x); |
| r = p[<span class="number">0</span>] + z * (p[<span class="number">1</span>] + z * (p[<span class="number">2</span>] + z * (p[<span class="number">3</span>] + z * (p[<span class="number">4</span>] + z * p[<span class="number">5</span>])))); |
| s = <span class="number">1.0 </span>+ z * (q[<span class="number">0</span>] + z * (q[<span class="number">1</span>] + z * (q[<span class="number">2</span>] + z * (q[<span class="number">3</span>] + z * (q[<span class="number">4</span>] + z * q[<span class="number">5</span>]))))); |
| <span class="kw">return </span>(<span class="number">0.375 </span>+ r / s) / x; |
| } |
| |
| <span class="comment">// PowerPC tests are failing on LLVM 13: https://github.com/rust-lang/rust/issues/88520 |
| </span><span class="attribute">#[cfg(not(target_arch = <span class="string">"powerpc64"</span>))] |
| #[cfg(test)] |
| </span><span class="kw">mod </span>tests { |
| <span class="kw">use super</span>::{j1f, y1f}; |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_j1f_2488() { |
| <span class="comment">// 0x401F3E49 |
| </span><span class="macro">assert_eq!</span>(j1f(<span class="number">2.4881766_f32</span>), <span class="number">0.49999475_f32</span>); |
| } |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_y1f_2002() { |
| <span class="comment">//allow slightly different result on x87 |
| </span><span class="kw">let </span>res = y1f(<span class="number">2.0000002_f32</span>); |
| <span class="kw">if </span><span class="macro">cfg!</span>(all(target_arch = <span class="string">"x86"</span>, not(target_feature = <span class="string">"sse2"</span>))) && (res == -<span class="number">0.10703231_f32</span>) |
| { |
| <span class="kw">return</span>; |
| } |
| <span class="macro">assert_eq!</span>(res, -<span class="number">0.10703229_f32</span>); |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="libm" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |