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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/float/k1f.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/float/k1f.c')
-rw-r--r--libm/float/k1f.c174
1 files changed, 0 insertions, 174 deletions
diff --git a/libm/float/k1f.c b/libm/float/k1f.c
deleted file mode 100644
index d5b9bdfce..000000000
--- a/libm/float/k1f.c
+++ /dev/null
@@ -1,174 +0,0 @@
-/* k1f.c
- *
- * Modified Bessel function, third kind, order one
- *
- *
- *
- * SYNOPSIS:
- *
- * float x, y, k1f();
- *
- * y = k1f( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Computes the modified Bessel function of the third kind
- * of order one of the argument.
- *
- * The range is partitioned into the two intervals [0,2] and
- * (2, infinity). Chebyshev polynomial expansions are employed
- * in each interval.
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * IEEE 0, 30 30000 4.6e-7 7.6e-8
- *
- * ERROR MESSAGES:
- *
- * message condition value returned
- * k1 domain x <= 0 MAXNUM
- *
- */
- /* k1ef.c
- *
- * Modified Bessel function, third kind, order one,
- * exponentially scaled
- *
- *
- *
- * SYNOPSIS:
- *
- * float x, y, k1ef();
- *
- * y = k1ef( x );
- *
- *
- *
- * DESCRIPTION:
- *
- * Returns exponentially scaled modified Bessel function
- * of the third kind of order one of the argument:
- *
- * k1e(x) = exp(x) * k1(x).
- *
- *
- *
- * ACCURACY:
- *
- * Relative error:
- * arithmetic domain # trials peak rms
- * IEEE 0, 30 30000 4.9e-7 6.7e-8
- * See k1().
- *
- */
-
-/*
-Cephes Math Library Release 2.2: June, 1992
-Copyright 1984, 1987, 1992 by Stephen L. Moshier
-Direct inquiries to 30 Frost Street, Cambridge, MA 02140
-*/
-
-#include <math.h>
-
-/* Chebyshev coefficients for x(K1(x) - log(x/2) I1(x))
- * in the interval [0,2].
- *
- * lim(x->0){ x(K1(x) - log(x/2) I1(x)) } = 1.
- */
-
-#define MINNUMF 6.0e-39
-static float A[] =
-{
--2.21338763073472585583E-8f,
--2.43340614156596823496E-6f,
--1.73028895751305206302E-4f,
--6.97572385963986435018E-3f,
--1.22611180822657148235E-1f,
--3.53155960776544875667E-1f,
- 1.52530022733894777053E0f
-};
-
-
-
-
-/* Chebyshev coefficients for exp(x) sqrt(x) K1(x)
- * in the interval [2,infinity].
- *
- * lim(x->inf){ exp(x) sqrt(x) K1(x) } = sqrt(pi/2).
- */
-
-static float B[] =
-{
- 2.01504975519703286596E-9f,
--1.03457624656780970260E-8f,
- 5.74108412545004946722E-8f,
--3.50196060308781257119E-7f,
- 2.40648494783721712015E-6f,
--1.93619797416608296024E-5f,
- 1.95215518471351631108E-4f,
--2.85781685962277938680E-3f,
- 1.03923736576817238437E-1f,
- 2.72062619048444266945E0f
-};
-
-
-
-extern float MAXNUMF;
-#ifdef ANSIC
-float chbevlf(float, float *, int);
-float expf(float), i1f(float), logf(float), sqrtf(float);
-#else
-float chbevlf(), expf(), i1f(), logf(), sqrtf();
-#endif
-
-float k1f(float xx)
-{
-float x, y;
-
-x = xx;
-if( x <= MINNUMF )
- {
- mtherr( "k1f", DOMAIN );
- return( MAXNUMF );
- }
-
-if( x <= 2.0f )
- {
- y = x * x - 2.0f;
- y = logf( 0.5f * x ) * i1f(x) + chbevlf( y, A, 7 ) / x;
- return( y );
- }
-
-return( expf(-x) * chbevlf( 8.0f/x - 2.0f, B, 10 ) / sqrtf(x) );
-
-}
-
-
-
-float k1ef( float xx )
-{
-float x, y;
-
-x = xx;
-if( x <= 0.0f )
- {
- mtherr( "k1ef", DOMAIN );
- return( MAXNUMF );
- }
-
-if( x <= 2.0f )
- {
- y = x * x - 2.0f;
- y = logf( 0.5f * x ) * i1f(x) + chbevlf( y, A, 7 ) / x;
- return( y * expf(x) );
- }
-
-return( chbevlf( 8.0f/x - 2.0f, B, 10 ) / sqrtf(x) );
-
-}