diff options
Diffstat (limited to 'vendor/libm-0.1.4/src/math/lgammaf_r.rs')
| -rw-r--r-- | vendor/libm-0.1.4/src/math/lgammaf_r.rs | 254 |
1 files changed, 0 insertions, 254 deletions
diff --git a/vendor/libm-0.1.4/src/math/lgammaf_r.rs b/vendor/libm-0.1.4/src/math/lgammaf_r.rs deleted file mode 100644 index 0745359a2..000000000 --- a/vendor/libm-0.1.4/src/math/lgammaf_r.rs +++ /dev/null @@ -1,254 +0,0 @@ -/* origin: FreeBSD /usr/src/lib/msun/src/e_lgammaf_r.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. - * ==================================================== - */ - -use super::{floorf, k_cosf, k_sinf, logf}; - -const PI: f32 = 3.1415927410e+00; /* 0x40490fdb */ -const A0: f32 = 7.7215664089e-02; /* 0x3d9e233f */ -const A1: f32 = 3.2246702909e-01; /* 0x3ea51a66 */ -const A2: f32 = 6.7352302372e-02; /* 0x3d89f001 */ -const A3: f32 = 2.0580807701e-02; /* 0x3ca89915 */ -const A4: f32 = 7.3855509982e-03; /* 0x3bf2027e */ -const A5: f32 = 2.8905137442e-03; /* 0x3b3d6ec6 */ -const A6: f32 = 1.1927076848e-03; /* 0x3a9c54a1 */ -const A7: f32 = 5.1006977446e-04; /* 0x3a05b634 */ -const A8: f32 = 2.2086278477e-04; /* 0x39679767 */ -const A9: f32 = 1.0801156895e-04; /* 0x38e28445 */ -const A10: f32 = 2.5214456400e-05; /* 0x37d383a2 */ -const A11: f32 = 4.4864096708e-05; /* 0x383c2c75 */ -const TC: f32 = 1.4616321325e+00; /* 0x3fbb16c3 */ -const TF: f32 = -1.2148628384e-01; /* 0xbdf8cdcd */ -/* TT = -(tail of TF) */ -const TT: f32 = 6.6971006518e-09; /* 0x31e61c52 */ -const T0: f32 = 4.8383611441e-01; /* 0x3ef7b95e */ -const T1: f32 = -1.4758771658e-01; /* 0xbe17213c */ -const T2: f32 = 6.4624942839e-02; /* 0x3d845a15 */ -const T3: f32 = -3.2788541168e-02; /* 0xbd064d47 */ -const T4: f32 = 1.7970675603e-02; /* 0x3c93373d */ -const T5: f32 = -1.0314224288e-02; /* 0xbc28fcfe */ -const T6: f32 = 6.1005386524e-03; /* 0x3bc7e707 */ -const T7: f32 = -3.6845202558e-03; /* 0xbb7177fe */ -const T8: f32 = 2.2596477065e-03; /* 0x3b141699 */ -const T9: f32 = -1.4034647029e-03; /* 0xbab7f476 */ -const T10: f32 = 8.8108185446e-04; /* 0x3a66f867 */ -const T11: f32 = -5.3859531181e-04; /* 0xba0d3085 */ -const T12: f32 = 3.1563205994e-04; /* 0x39a57b6b */ -const T13: f32 = -3.1275415677e-04; /* 0xb9a3f927 */ -const T14: f32 = 3.3552918467e-04; /* 0x39afe9f7 */ -const U0: f32 = -7.7215664089e-02; /* 0xbd9e233f */ -const U1: f32 = 6.3282704353e-01; /* 0x3f2200f4 */ -const U2: f32 = 1.4549225569e+00; /* 0x3fba3ae7 */ -const U3: f32 = 9.7771751881e-01; /* 0x3f7a4bb2 */ -const U4: f32 = 2.2896373272e-01; /* 0x3e6a7578 */ -const U5: f32 = 1.3381091878e-02; /* 0x3c5b3c5e */ -const V1: f32 = 2.4559779167e+00; /* 0x401d2ebe */ -const V2: f32 = 2.1284897327e+00; /* 0x4008392d */ -const V3: f32 = 7.6928514242e-01; /* 0x3f44efdf */ -const V4: f32 = 1.0422264785e-01; /* 0x3dd572af */ -const V5: f32 = 3.2170924824e-03; /* 0x3b52d5db */ -const S0: f32 = -7.7215664089e-02; /* 0xbd9e233f */ -const S1: f32 = 2.1498242021e-01; /* 0x3e5c245a */ -const S2: f32 = 3.2577878237e-01; /* 0x3ea6cc7a */ -const S3: f32 = 1.4635047317e-01; /* 0x3e15dce6 */ -const S4: f32 = 2.6642270386e-02; /* 0x3cda40e4 */ -const S5: f32 = 1.8402845599e-03; /* 0x3af135b4 */ -const S6: f32 = 3.1947532989e-05; /* 0x3805ff67 */ -const R1: f32 = 1.3920053244e+00; /* 0x3fb22d3b */ -const R2: f32 = 7.2193557024e-01; /* 0x3f38d0c5 */ -const R3: f32 = 1.7193385959e-01; /* 0x3e300f6e */ -const R4: f32 = 1.8645919859e-02; /* 0x3c98bf54 */ -const R5: f32 = 7.7794247773e-04; /* 0x3a4beed6 */ -const R6: f32 = 7.3266842264e-06; /* 0x36f5d7bd */ -const W0: f32 = 4.1893854737e-01; /* 0x3ed67f1d */ -const W1: f32 = 8.3333335817e-02; /* 0x3daaaaab */ -const W2: f32 = -2.7777778450e-03; /* 0xbb360b61 */ -const W3: f32 = 7.9365057172e-04; /* 0x3a500cfd */ -const W4: f32 = -5.9518753551e-04; /* 0xba1c065c */ -const W5: f32 = 8.3633989561e-04; /* 0x3a5b3dd2 */ -const W6: f32 = -1.6309292987e-03; /* 0xbad5c4e8 */ - -/* sin(PI*x) assuming x > 2^-100, if sin(PI*x)==0 the sign is arbitrary */ -fn sin_pi(mut x: f32) -> f32 { - let mut y: f64; - let mut n: isize; - - /* spurious inexact if odd int */ - x = 2.0 * (x * 0.5 - floorf(x * 0.5)); /* x mod 2.0 */ - - n = (x * 4.0) as isize; - n = (n + 1) / 2; - y = (x as f64) - (n as f64) * 0.5; - y *= 3.14159265358979323846; - match n { - 1 => k_cosf(y), - 2 => k_sinf(-y), - 3 => -k_cosf(y), - 0 | _ => k_sinf(y), - } -} - -pub fn lgammaf_r(mut x: f32) -> (f32, i32) { - let u = x.to_bits(); - let mut t: f32; - let y: f32; - let mut z: f32; - let nadj: f32; - let p: f32; - let p1: f32; - let p2: f32; - let p3: f32; - let q: f32; - let mut r: f32; - let w: f32; - let ix: u32; - let i: i32; - let sign: bool; - let mut signgam: i32; - - /* purge off +-inf, NaN, +-0, tiny and negative arguments */ - signgam = 1; - sign = (u >> 31) != 0; - ix = u & 0x7fffffff; - if ix >= 0x7f800000 { - return (x * x, signgam); - } - if ix < 0x35000000 { - /* |x| < 2**-21, return -log(|x|) */ - if sign { - signgam = -1; - x = -x; - } - return (-logf(x), signgam); - } - if sign { - x = -x; - t = sin_pi(x); - if t == 0.0 { - /* -integer */ - return (1.0 / (x - x), signgam); - } - if t > 0.0 { - signgam = -1; - } else { - t = -t; - } - nadj = logf(PI / (t * x)); - } else { - nadj = 0.0; - } - - /* purge off 1 and 2 */ - if ix == 0x3f800000 || ix == 0x40000000 { - r = 0.0; - } - /* for x < 2.0 */ - else if ix < 0x40000000 { - if ix <= 0x3f666666 { - /* lgamma(x) = lgamma(x+1)-log(x) */ - r = -logf(x); - if ix >= 0x3f3b4a20 { - y = 1.0 - x; - i = 0; - } else if ix >= 0x3e6d3308 { - y = x - (TC - 1.0); - i = 1; - } else { - y = x; - i = 2; - } - } else { - r = 0.0; - if ix >= 0x3fdda618 { - /* [1.7316,2] */ - y = 2.0 - x; - i = 0; - } else if ix >= 0x3F9da620 { - /* [1.23,1.73] */ - y = x - TC; - i = 1; - } else { - y = x - 1.0; - i = 2; - } - } - match i { - 0 => { - z = y * y; - p1 = A0 + z * (A2 + z * (A4 + z * (A6 + z * (A8 + z * A10)))); - p2 = z * (A1 + z * (A3 + z * (A5 + z * (A7 + z * (A9 + z * A11))))); - p = y * p1 + p2; - r += p - 0.5 * y; - } - 1 => { - z = y * y; - w = z * y; - p1 = T0 + w * (T3 + w * (T6 + w * (T9 + w * T12))); /* parallel comp */ - p2 = T1 + w * (T4 + w * (T7 + w * (T10 + w * T13))); - p3 = T2 + w * (T5 + w * (T8 + w * (T11 + w * T14))); - p = z * p1 - (TT - w * (p2 + y * p3)); - r += TF + p; - } - 2 => { - p1 = y * (U0 + y * (U1 + y * (U2 + y * (U3 + y * (U4 + y * U5))))); - p2 = 1.0 + y * (V1 + y * (V2 + y * (V3 + y * (V4 + y * V5)))); - r += -0.5 * y + p1 / p2; - } - #[cfg(feature = "checked")] - _ => unreachable!(), - #[cfg(not(feature = "checked"))] - _ => {} - } - } else if ix < 0x41000000 { - /* x < 8.0 */ - i = x as i32; - y = x - (i as f32); - p = y * (S0 + y * (S1 + y * (S2 + y * (S3 + y * (S4 + y * (S5 + y * S6)))))); - q = 1.0 + y * (R1 + y * (R2 + y * (R3 + y * (R4 + y * (R5 + y * R6))))); - r = 0.5 * y + p / q; - z = 1.0; /* lgamma(1+s) = log(s) + lgamma(s) */ - // TODO: In C, this was implemented using switch jumps with fallthrough. - // Does this implementation have performance problems? - if i >= 7 { - z *= y + 6.0; - } - if i >= 6 { - z *= y + 5.0; - } - if i >= 5 { - z *= y + 4.0; - } - if i >= 4 { - z *= y + 3.0; - } - if i >= 3 { - z *= y + 2.0; - r += logf(z); - } - } else if ix < 0x5c800000 { - /* 8.0 <= x < 2**58 */ - t = logf(x); - z = 1.0 / x; - y = z * z; - w = W0 + z * (W1 + y * (W2 + y * (W3 + y * (W4 + y * (W5 + y * W6))))); - r = (x - 0.5) * (t - 1.0) + w; - } else { - /* 2**58 <= x <= inf */ - r = x * (logf(x) - 1.0); - } - if sign { - r = nadj - r; - } - return (r, signgam); -} |