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authorEric Andersen <andersen@codepoet.org>2001-11-22 14:04:29 +0000
committerEric Andersen <andersen@codepoet.org>2001-11-22 14:04:29 +0000
commit7ce331c01ce6eb7b3f5c715a38a24359da9c6ee2 (patch)
tree3a7e8476e868ae15f4da1b7ce26b2db6f434468c /libm/ldouble/tanhl.c
parentc117dd5fb183afb1a4790a6f6110d88704be6bf8 (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.c129
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 );
-}