diff options
author | Eric Andersen <andersen@codepoet.org> | 2001-11-22 14:04:29 +0000 |
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committer | Eric Andersen <andersen@codepoet.org> | 2001-11-22 14:04:29 +0000 |
commit | 7ce331c01ce6eb7b3f5c715a38a24359da9c6ee2 (patch) | |
tree | 3a7e8476e868ae15f4da1b7ce26b2db6f434468c /libm/ldouble/tanhl.c | |
parent | c117dd5fb183afb1a4790a6f6110d88704be6bf8 (diff) |
Totally rework the math library, this time based on the MacOs X
math library (which is itself based on the math lib from FreeBSD).
-Erik
Diffstat (limited to 'libm/ldouble/tanhl.c')
-rw-r--r-- | libm/ldouble/tanhl.c | 129 |
1 files changed, 0 insertions, 129 deletions
diff --git a/libm/ldouble/tanhl.c b/libm/ldouble/tanhl.c deleted file mode 100644 index 42c7133c3..000000000 --- a/libm/ldouble/tanhl.c +++ /dev/null @@ -1,129 +0,0 @@ -/* tanhl.c - * - * Hyperbolic tangent, long double precision - * - * - * - * SYNOPSIS: - * - * long double x, y, tanhl(); - * - * y = tanhl( x ); - * - * - * - * DESCRIPTION: - * - * Returns hyperbolic tangent of argument in the range MINLOGL to - * MAXLOGL. - * - * A rational function is used for |x| < 0.625. The form - * x + x**3 P(x)/Q(x) of Cody _& Waite is employed. - * Otherwise, - * tanh(x) = sinh(x)/cosh(x) = 1 - 2/(exp(2x) + 1). - * - * - * - * ACCURACY: - * - * Relative error: - * arithmetic domain # trials peak rms - * IEEE -2,2 30000 1.3e-19 2.4e-20 - * - */ - -/* -Cephes Math Library Release 2.7: May, 1998 -Copyright 1984, 1987, 1989, 1998 by Stephen L. Moshier -*/ - -#include <math.h> - -#ifdef UNK -static long double P[] = { --6.8473739392677100872869E-5L, --9.5658283111794641589011E-1L, --8.4053568599672284488465E1L, --1.3080425704712825945553E3L, -}; -static long double Q[] = { -/* 1.0000000000000000000000E0L,*/ - 9.6259501838840336946872E1L, - 1.8218117903645559060232E3L, - 3.9241277114138477845780E3L, -}; -#endif - -#ifdef IBMPC -static short P[] = { -0xd2a4,0x1b0c,0x8f15,0x8f99,0xbff1, XPD -0x5959,0x9111,0x9cc7,0xf4e2,0xbffe, XPD -0xb576,0xef5e,0x6d57,0xa81b,0xc005, XPD -0xe3be,0xbfbd,0x5cbc,0xa381,0xc009, XPD -}; -static short Q[] = { -/*0x0000,0x0000,0x0000,0x8000,0x3fff,*/ -0x687f,0xce24,0xdd6c,0xc084,0x4005, XPD -0x3793,0xc95f,0xfa2f,0xe3b9,0x4009, XPD -0xd5a2,0x1f9c,0x0b1b,0xf542,0x400a, XPD -}; -#endif - -#ifdef MIEEE -static long P[] = { -0xbff10000,0x8f998f15,0x1b0cd2a4, -0xbffe0000,0xf4e29cc7,0x91115959, -0xc0050000,0xa81b6d57,0xef5eb576, -0xc0090000,0xa3815cbc,0xbfbde3be, -}; -static long Q[] = { -/*0x3fff0000,0x80000000,0x00000000,*/ -0x40050000,0xc084dd6c,0xce24687f, -0x40090000,0xe3b9fa2f,0xc95f3793, -0x400a0000,0xf5420b1b,0x1f9cd5a2, -}; -#endif - -extern long double MAXLOGL; -#ifdef ANSIPROT -extern long double fabsl ( long double ); -extern long double expl ( long double ); -extern long double polevll ( long double, void *, int ); -extern long double p1evll ( long double, void *, int ); -#else -long double fabsl(), expl(), polevll(), p1evll(); -#endif - -long double tanhl(x) -long double x; -{ -long double s, z; - -#ifdef MINUSZERO -if( x == 0.0L ) - return(x); -#endif -z = fabsl(x); -if( z > 0.5L * MAXLOGL ) - { - if( x > 0 ) - return( 1.0L ); - else - return( -1.0L ); - } -if( z >= 0.625L ) - { - s = expl(2.0*z); - z = 1.0L - 2.0/(s + 1.0L); - if( x < 0 ) - z = -z; - } -else - { - s = x * x; - z = polevll( s, P, 3 )/p1evll(s, Q, 3); - z = x * s * z; - z = x + z; - } -return( z ); -} |