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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/double/acosh.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/double/acosh.c')
-rw-r--r--libm/double/acosh.c167
1 files changed, 0 insertions, 167 deletions
diff --git a/libm/double/acosh.c b/libm/double/acosh.c
deleted file mode 100644
index 49d9a40e2..000000000
--- a/libm/double/acosh.c
+++ /dev/null
@@ -1,167 +0,0 @@
-/* acosh.c
- *
- * Inverse hyperbolic cosine
- *
- *
- *
- * SYNOPSIS:
- *
- * double x, y, acosh();
- *
- * y = acosh( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns inverse hyperbolic cosine of argument.
- *
- * If 1 <= x < 1.5, a rational approximation
- *
- * sqrt(z) * P(z)/Q(z)
- *
- * where z = x-1, is used. Otherwise,
- *
- * acosh(x) = log( x + sqrt( (x-1)(x+1) ).
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * DEC 1,3 30000 4.2e-17 1.1e-17
- * IEEE 1,3 30000 4.6e-16 8.7e-17
- *
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * acosh domain |x| < 1 NAN
- *
- */
-
-/* acosh.c */
-
-/*
-Cephes Math Library Release 2.8: June, 2000
-Copyright 1984, 1995, 2000 by Stephen L. Moshier
-*/
-
-
-/* acosh(z) = sqrt(x) * R(x), z = x + 1, interval 0 < x < 0.5 */
-
-#include <math.h>
-
-#ifdef UNK
-static double P[] = {
- 1.18801130533544501356E2,
- 3.94726656571334401102E3,
- 3.43989375926195455866E4,
- 1.08102874834699867335E5,
- 1.10855947270161294369E5
-};
-static double Q[] = {
-/* 1.00000000000000000000E0,*/
- 1.86145380837903397292E2,
- 4.15352677227719831579E3,
- 2.97683430363289370382E4,
- 8.29725251988426222434E4,
- 7.83869920495893927727E4
-};
-#endif
-
-#ifdef DEC
-static unsigned short P[] = {
-0041755,0115055,0144002,0146444,
-0043166,0132103,0155150,0150302,
-0044006,0057360,0003021,0162753,
-0044323,0021557,0175225,0056253,
-0044330,0101771,0040046,0006636
-};
-static unsigned short Q[] = {
-/*0040200,0000000,0000000,0000000,*/
-0042072,0022467,0126670,0041232,
-0043201,0146066,0152142,0034015,
-0043750,0110257,0121165,0026100,
-0044242,0007103,0034667,0033173,
-0044231,0014576,0175573,0017472
-};
-#endif
-
-#ifdef IBMPC
-static unsigned short P[] = {
-0x59a4,0xb900,0xb345,0x405d,
-0x1a18,0x7b4d,0xd688,0x40ae,
-0x3cbd,0x00c2,0xcbde,0x40e0,
-0xab95,0xff52,0x646d,0x40fa,
-0xc1b4,0x2804,0x107f,0x40fb
-};
-static unsigned short Q[] = {
-/*0x0000,0x0000,0x0000,0x3ff0,*/
-0x0853,0xf5b7,0x44a6,0x4067,
-0x4702,0xda8c,0x3986,0x40b0,
-0xa588,0xf44e,0x1215,0x40dd,
-0xe6cf,0x6736,0x41c8,0x40f4,
-0x63e7,0xdf6f,0x232f,0x40f3
-};
-#endif
-
-#ifdef MIEEE
-static unsigned short P[] = {
-0x405d,0xb345,0xb900,0x59a4,
-0x40ae,0xd688,0x7b4d,0x1a18,
-0x40e0,0xcbde,0x00c2,0x3cbd,
-0x40fa,0x646d,0xff52,0xab95,
-0x40fb,0x107f,0x2804,0xc1b4
-};
-static unsigned short Q[] = {
-0x4067,0x44a6,0xf5b7,0x0853,
-0x40b0,0x3986,0xda8c,0x4702,
-0x40dd,0x1215,0xf44e,0xa588,
-0x40f4,0x41c8,0x6736,0xe6cf,
-0x40f3,0x232f,0xdf6f,0x63e7,
-};
-#endif
-
-#ifdef ANSIPROT
-extern double polevl ( double, void *, int );
-extern double p1evl ( double, void *, int );
-extern double log ( double );
-extern double sqrt ( double );
-#else
-double log(), sqrt(), polevl(), p1evl();
-#endif
-extern double LOGE2, INFINITY, NAN;
-
-double acosh(x)
-double x;
-{
-double a, z;
-
-if( x < 1.0 )
- {
- mtherr( "acosh", DOMAIN );
- return(NAN);
- }
-
-if( x > 1.0e8 )
- {
-#ifdef INFINITIES
- if( x == INFINITY )
- return( INFINITY );
-#endif
- return( log(x) + LOGE2 );
- }
-
-z = x - 1.0;
-
-if( z < 0.5 )
- {
- a = sqrt(z) * (polevl(z, P, 4) / p1evl(z, Q, 5) );
- return( a );
- }
-
-a = sqrt( z*(x+1.0) );
-return( log(x + a) );
-}