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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/unity.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/unity.c')
-rw-r--r--libm/double/unity.c138
1 files changed, 0 insertions, 138 deletions
diff --git a/libm/double/unity.c b/libm/double/unity.c
deleted file mode 100644
index 9223e0edf..000000000
--- a/libm/double/unity.c
+++ /dev/null
@@ -1,138 +0,0 @@
-/* unity.c
- *
- * Relative error approximations for function arguments near
- * unity.
- *
- * log1p(x) = log(1+x)
- * expm1(x) = exp(x) - 1
- * cosm1(x) = cos(x) - 1
- *
- */
-
-#include <math.h>
-
-#ifdef ANSIPROT
-extern int isnan (double);
-extern int isfinite (double);
-extern double log ( double );
-extern double polevl ( double, void *, int );
-extern double p1evl ( double, void *, int );
-extern double exp ( double );
-extern double cos ( double );
-#else
-double log(), polevl(), p1evl(), exp(), cos();
-int isnan(), isfinite();
-#endif
-extern double INFINITY;
-
-/* log1p(x) = log(1 + x) */
-
-/* Coefficients for log(1+x) = x - x**2/2 + x**3 P(x)/Q(x)
- * 1/sqrt(2) <= x < sqrt(2)
- * Theoretical peak relative error = 2.32e-20
- */
-static double LP[] = {
- 4.5270000862445199635215E-5,
- 4.9854102823193375972212E-1,
- 6.5787325942061044846969E0,
- 2.9911919328553073277375E1,
- 6.0949667980987787057556E1,
- 5.7112963590585538103336E1,
- 2.0039553499201281259648E1,
-};
-static double LQ[] = {
-/* 1.0000000000000000000000E0,*/
- 1.5062909083469192043167E1,
- 8.3047565967967209469434E1,
- 2.2176239823732856465394E2,
- 3.0909872225312059774938E2,
- 2.1642788614495947685003E2,
- 6.0118660497603843919306E1,
-};
-
-#define SQRTH 0.70710678118654752440
-#define SQRT2 1.41421356237309504880
-
-double log1p(x)
-double x;
-{
-double z;
-
-z = 1.0 + x;
-if( (z < SQRTH) || (z > SQRT2) )
- return( log(z) );
-z = x*x;
-z = -0.5 * z + x * ( z * polevl( x, LP, 6 ) / p1evl( x, LQ, 6 ) );
-return (x + z);
-}
-
-
-
-/* expm1(x) = exp(x) - 1 */
-
-/* e^x = 1 + 2x P(x^2)/( Q(x^2) - P(x^2) )
- * -0.5 <= x <= 0.5
- */
-
-static double EP[3] = {
- 1.2617719307481059087798E-4,
- 3.0299440770744196129956E-2,
- 9.9999999999999999991025E-1,
-};
-static double EQ[4] = {
- 3.0019850513866445504159E-6,
- 2.5244834034968410419224E-3,
- 2.2726554820815502876593E-1,
- 2.0000000000000000000897E0,
-};
-
-double expm1(x)
-double x;
-{
-double r, xx;
-
-#ifdef NANS
-if( isnan(x) )
- return(x);
-#endif
-#ifdef INFINITIES
-if( x == INFINITY )
- return(INFINITY);
-if( x == -INFINITY )
- return(-1.0);
-#endif
-if( (x < -0.5) || (x > 0.5) )
- return( exp(x) - 1.0 );
-xx = x * x;
-r = x * polevl( xx, EP, 2 );
-r = r/( polevl( xx, EQ, 3 ) - r );
-return (r + r);
-}
-
-
-
-/* cosm1(x) = cos(x) - 1 */
-
-static double coscof[7] = {
- 4.7377507964246204691685E-14,
--1.1470284843425359765671E-11,
- 2.0876754287081521758361E-9,
--2.7557319214999787979814E-7,
- 2.4801587301570552304991E-5,
--1.3888888888888872993737E-3,
- 4.1666666666666666609054E-2,
-};
-
-extern double PIO4;
-
-double cosm1(x)
-double x;
-{
-double xx;
-
-if( (x < -PIO4) || (x > PIO4) )
- return( cos(x) - 1.0 );
-xx = x * x;
-xx = -0.5*xx + xx * xx * polevl( xx, coscof, 6 );
-return xx;
-}