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Diffstat (limited to 'sysdeps/generic/exp__E.c')
| -rw-r--r-- | sysdeps/generic/exp__E.c | 136 |
1 files changed, 0 insertions, 136 deletions
diff --git a/sysdeps/generic/exp__E.c b/sysdeps/generic/exp__E.c deleted file mode 100644 index ab972477a0..0000000000 --- a/sysdeps/generic/exp__E.c +++ /dev/null @@ -1,136 +0,0 @@ -/* - * Copyright (c) 1985, 1993 - * The Regents of the University of California. All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. All advertising materials mentioning features or use of this software - * must display the following acknowledgement: - * This product includes software developed by the University of - * California, Berkeley and its contributors. - * 4. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -#ifndef lint -static char sccsid[] = "@(#)exp__E.c 8.1 (Berkeley) 6/4/93"; -#endif /* not lint */ - -/* exp__E(x,c) - * ASSUMPTION: c << x SO THAT fl(x+c)=x. - * (c is the correction term for x) - * exp__E RETURNS - * - * / exp(x+c) - 1 - x , 1E-19 < |x| < .3465736 - * exp__E(x,c) = | - * \ 0 , |x| < 1E-19. - * - * DOUBLE PRECISION (IEEE 53 bits, VAX D FORMAT 56 BITS) - * KERNEL FUNCTION OF EXP, EXPM1, POW FUNCTIONS - * CODED IN C BY K.C. NG, 1/31/85; - * REVISED BY K.C. NG on 3/16/85, 4/16/85. - * - * Required system supported function: - * copysign(x,y) - * - * Method: - * 1. Rational approximation. Let r=x+c. - * Based on - * 2 * sinh(r/2) - * exp(r) - 1 = ---------------------- , - * cosh(r/2) - sinh(r/2) - * exp__E(r) is computed using - * x*x (x/2)*W - ( Q - ( 2*P + x*P ) ) - * --- + (c + x*[---------------------------------- + c ]) - * 2 1 - W - * where P := p1*x^2 + p2*x^4, - * Q := q1*x^2 + q2*x^4 (for 56 bits precision, add q3*x^6) - * W := x/2-(Q-x*P), - * - * (See the listing below for the values of p1,p2,q1,q2,q3. The poly- - * nomials P and Q may be regarded as the approximations to sinh - * and cosh : - * sinh(r/2) = r/2 + r * P , cosh(r/2) = 1 + Q . ) - * - * The coefficients were obtained by a special Remez algorithm. - * - * Approximation error: - * - * | exp(x) - 1 | 2**(-57), (IEEE double) - * | ------------ - (exp__E(x,0)+x)/x | <= - * | x | 2**(-69). (VAX D) - * - * Constants: - * The hexadecimal values are the intended ones for the following constants. - * The decimal values may be used, provided that the compiler will convert - * from decimal to binary accurately enough to produce the hexadecimal values - * shown. - */ - -#include "mathimpl.h" - -vc(p1, 1.5150724356786683059E-2 ,3abe,3d78,066a,67e1, -6, .F83ABE67E1066A) -vc(p2, 6.3112487873718332688E-5 ,5b42,3984,0173,48cd, -13, .845B4248CD0173) -vc(q1, 1.1363478204690669916E-1 ,b95a,3ee8,ec45,44a2, -3, .E8B95A44A2EC45) -vc(q2, 1.2624568129896839182E-3 ,7905,3ba5,f5e7,72e4, -9, .A5790572E4F5E7) -vc(q3, 1.5021856115869022674E-6 ,9eb4,36c9,c395,604a, -19, .C99EB4604AC395) - -ic(p1, 1.3887401997267371720E-2, -7, 1.C70FF8B3CC2CF) -ic(p2, 3.3044019718331897649E-5, -15, 1.15317DF4526C4) -ic(q1, 1.1110813732786649355E-1, -4, 1.C719538248597) -ic(q2, 9.9176615021572857300E-4, -10, 1.03FC4CB8C98E8) - -#ifdef vccast -#define p1 vccast(p1) -#define p2 vccast(p2) -#define q1 vccast(q1) -#define q2 vccast(q2) -#define q3 vccast(q3) -#endif - -double __exp__E(x,c) -double x,c; -{ - const static double zero=0.0, one=1.0, half=1.0/2.0, small=1.0E-19; - double z,p,q,xp,xh,w; - if(copysign(x,one)>small) { - z = x*x ; - p = z*( p1 +z* p2 ); -#if defined(vax)||defined(tahoe) - q = z*( q1 +z*( q2 +z* q3 )); -#else /* defined(vax)||defined(tahoe) */ - q = z*( q1 +z* q2 ); -#endif /* defined(vax)||defined(tahoe) */ - xp= x*p ; - xh= x*half ; - w = xh-(q-xp) ; - p = p+p; - c += x*((xh*w-(q-(p+xp)))/(one-w)+c); - return(z*half+c); - } - /* end of |x| > small */ - - else { - if(x!=zero) one+small; /* raise the inexact flag */ - return(copysign(zero,x)); - } -} |