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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/spence.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/spence.c')
-rw-r--r--libm/double/spence.c205
1 files changed, 0 insertions, 205 deletions
diff --git a/libm/double/spence.c b/libm/double/spence.c
deleted file mode 100644
index e2a56176b..000000000
--- a/libm/double/spence.c
+++ /dev/null
@@ -1,205 +0,0 @@
-/* spence.c
- *
- * Dilogarithm
- *
- *
- *
- * SYNOPSIS:
- *
- * double x, y, spence();
- *
- * y = spence( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Computes the integral
- *
- * x
- * -
- * | | log t
- * spence(x) = - | ----- dt
- * | | t - 1
- * -
- * 1
- *
- * for x >= 0. A rational approximation gives the integral in
- * the interval (0.5, 1.5). Transformation formulas for 1/x
- * and 1-x are employed outside the basic expansion range.
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * IEEE 0,4 30000 3.9e-15 5.4e-16
- * DEC 0,4 3000 2.5e-16 4.5e-17
- *
- *
- */
-
-/* spence.c */
-
-
-/*
-Cephes Math Library Release 2.8: June, 2000
-Copyright 1985, 1987, 1989, 2000 by Stephen L. Moshier
-*/
-
-#include <math.h>
-
-#ifdef UNK
-static double A[8] = {
- 4.65128586073990045278E-5,
- 7.31589045238094711071E-3,
- 1.33847639578309018650E-1,
- 8.79691311754530315341E-1,
- 2.71149851196553469920E0,
- 4.25697156008121755724E0,
- 3.29771340985225106936E0,
- 1.00000000000000000126E0,
-};
-static double B[8] = {
- 6.90990488912553276999E-4,
- 2.54043763932544379113E-2,
- 2.82974860602568089943E-1,
- 1.41172597751831069617E0,
- 3.63800533345137075418E0,
- 5.03278880143316990390E0,
- 3.54771340985225096217E0,
- 9.99999999999999998740E-1,
-};
-#endif
-#ifdef DEC
-static unsigned short A[32] = {
-0034503,0013315,0034120,0157771,
-0036357,0135043,0016766,0150637,
-0037411,0007533,0005212,0161475,
-0040141,0031563,0023217,0120331,
-0040455,0104461,0007002,0155522,
-0040610,0034434,0065721,0120465,
-0040523,0006674,0105671,0054427,
-0040200,0000000,0000000,0000000,
-};
-static unsigned short B[32] = {
-0035465,0021626,0032367,0144157,
-0036720,0016326,0134431,0000406,
-0037620,0161024,0133701,0120766,
-0040264,0131557,0152055,0064512,
-0040550,0152424,0051166,0034272,
-0040641,0006233,0014672,0111572,
-0040543,0006674,0105671,0054425,
-0040200,0000000,0000000,0000000,
-};
-#endif
-#ifdef IBMPC
-static unsigned short A[32] = {
-0x1bff,0xa70a,0x62d9,0x3f08,
-0xda34,0x63be,0xf744,0x3f7d,
-0x5c68,0x6151,0x21eb,0x3fc1,
-0xf41b,0x64d1,0x266e,0x3fec,
-0x5b6a,0x21c0,0xb126,0x4005,
-0x3427,0x8d7a,0x0723,0x4011,
-0x2b23,0x9177,0x61b7,0x400a,
-0x0000,0x0000,0x0000,0x3ff0,
-};
-static unsigned short B[32] = {
-0xf90e,0xc69e,0xa472,0x3f46,
-0x2021,0xd723,0x039a,0x3f9a,
-0x343f,0x96f8,0x1c42,0x3fd2,
-0xad29,0xfa85,0x966d,0x3ff6,
-0xc717,0x8a4e,0x1aa2,0x400d,
-0x526f,0x6337,0x2193,0x4014,
-0x2b23,0x9177,0x61b7,0x400c,
-0x0000,0x0000,0x0000,0x3ff0,
-};
-#endif
-#ifdef MIEEE
-static unsigned short A[32] = {
-0x3f08,0x62d9,0xa70a,0x1bff,
-0x3f7d,0xf744,0x63be,0xda34,
-0x3fc1,0x21eb,0x6151,0x5c68,
-0x3fec,0x266e,0x64d1,0xf41b,
-0x4005,0xb126,0x21c0,0x5b6a,
-0x4011,0x0723,0x8d7a,0x3427,
-0x400a,0x61b7,0x9177,0x2b23,
-0x3ff0,0x0000,0x0000,0x0000,
-};
-static unsigned short B[32] = {
-0x3f46,0xa472,0xc69e,0xf90e,
-0x3f9a,0x039a,0xd723,0x2021,
-0x3fd2,0x1c42,0x96f8,0x343f,
-0x3ff6,0x966d,0xfa85,0xad29,
-0x400d,0x1aa2,0x8a4e,0xc717,
-0x4014,0x2193,0x6337,0x526f,
-0x400c,0x61b7,0x9177,0x2b23,
-0x3ff0,0x0000,0x0000,0x0000,
-};
-#endif
-
-#ifdef ANSIPROT
-extern double fabs ( double );
-extern double log ( double );
-extern double polevl ( double, void *, int );
-#else
-double fabs(), log(), polevl();
-#endif
-extern double PI, MACHEP;
-
-double spence(x)
-double x;
-{
-double w, y, z;
-int flag;
-
-if( x < 0.0 )
- {
- mtherr( "spence", DOMAIN );
- return(0.0);
- }
-
-if( x == 1.0 )
- return( 0.0 );
-
-if( x == 0.0 )
- return( PI*PI/6.0 );
-
-flag = 0;
-
-if( x > 2.0 )
- {
- x = 1.0/x;
- flag |= 2;
- }
-
-if( x > 1.5 )
- {
- w = (1.0/x) - 1.0;
- flag |= 2;
- }
-
-else if( x < 0.5 )
- {
- w = -x;
- flag |= 1;
- }
-
-else
- w = x - 1.0;
-
-
-y = -w * polevl( w, A, 7) / polevl( w, B, 7 );
-
-if( flag & 1 )
- y = (PI * PI)/6.0 - log(x) * log(1.0-x) - y;
-
-if( flag & 2 )
- {
- z = log(x);
- y = -0.5 * z * z - y;
- }
-
-return( y );
-}