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Diffstat (limited to 'libm/float/fresnlf.c')
-rw-r--r-- | libm/float/fresnlf.c | 173 |
1 files changed, 0 insertions, 173 deletions
diff --git a/libm/float/fresnlf.c b/libm/float/fresnlf.c deleted file mode 100644 index d6ae773b1..000000000 --- a/libm/float/fresnlf.c +++ /dev/null @@ -1,173 +0,0 @@ -/* fresnlf.c - * - * Fresnel integral - * - * - * - * SYNOPSIS: - * - * float x, S, C; - * void fresnlf(); - * - * fresnlf( x, _&S, _&C ); - * - * - * DESCRIPTION: - * - * Evaluates the Fresnel integrals - * - * x - * - - * | | - * C(x) = | cos(pi/2 t**2) dt, - * | | - * - - * 0 - * - * x - * - - * | | - * S(x) = | sin(pi/2 t**2) dt. - * | | - * - - * 0 - * - * - * The integrals are evaluated by power series for small x. - * For x >= 1 auxiliary functions f(x) and g(x) are employed - * such that - * - * C(x) = 0.5 + f(x) sin( pi/2 x**2 ) - g(x) cos( pi/2 x**2 ) - * S(x) = 0.5 - f(x) cos( pi/2 x**2 ) - g(x) sin( pi/2 x**2 ) - * - * - * - * ACCURACY: - * - * Relative error. - * - * Arithmetic function domain # trials peak rms - * IEEE S(x) 0, 10 30000 1.1e-6 1.9e-7 - * IEEE C(x) 0, 10 30000 1.1e-6 2.0e-7 - */ - -/* -Cephes Math Library Release 2.1: January, 1989 -Copyright 1984, 1987, 1989 by Stephen L. Moshier -Direct inquiries to 30 Frost Street, Cambridge, MA 02140 -*/ - -#include <math.h> - -/* S(x) for small x */ -static float sn[7] = { - 1.647629463788700E-009, --1.522754752581096E-007, - 8.424748808502400E-006, --3.120693124703272E-004, - 7.244727626597022E-003, --9.228055941124598E-002, - 5.235987735681432E-001 -}; - -/* C(x) for small x */ -static float cn[7] = { - 1.416802502367354E-008, --1.157231412229871E-006, - 5.387223446683264E-005, --1.604381798862293E-003, - 2.818489036795073E-002, --2.467398198317899E-001, - 9.999999760004487E-001 -}; - - -/* Auxiliary function f(x) */ -static float fn[8] = { --1.903009855649792E+012, - 1.355942388050252E+011, --4.158143148511033E+009, - 7.343848463587323E+007, --8.732356681548485E+005, - 8.560515466275470E+003, --1.032877601091159E+002, - 2.999401847870011E+000 -}; - -/* Auxiliary function g(x) */ -static float gn[8] = { --1.860843997624650E+011, - 1.278350673393208E+010, --3.779387713202229E+008, - 6.492611570598858E+006, --7.787789623358162E+004, - 8.602931494734327E+002, --1.493439396592284E+001, - 9.999841934744914E-001 -}; - - -extern float PIF, PIO2F; - -#define fabsf(x) ( (x) < 0 ? -(x) : (x) ) - -#ifdef ANSIC -float polevlf( float, float *, int ); -float cosf(float), sinf(float); -#else -float polevlf(), cosf(), sinf(); -#endif - -void fresnlf( float xxa, float *ssa, float *cca ) -{ -float f, g, cc, ss, c, s, t, u, x, x2; - -x = xxa; -x = fabsf(x); -x2 = x * x; -if( x2 < 2.5625 ) - { - t = x2 * x2; - ss = x * x2 * polevlf( t, sn, 6); - cc = x * polevlf( t, cn, 6); - goto done; - } - -if( x > 36974.0 ) - { - cc = 0.5; - ss = 0.5; - goto done; - } - - -/* Asymptotic power series auxiliary functions - * for large argument - */ - x2 = x * x; - t = PIF * x2; - u = 1.0/(t * t); - t = 1.0/t; - f = 1.0 - u * polevlf( u, fn, 7); - g = t * polevlf( u, gn, 7); - - t = PIO2F * x2; - c = cosf(t); - s = sinf(t); - t = PIF * x; - cc = 0.5 + (f * s - g * c)/t; - ss = 0.5 - (f * c + g * s)/t; - -done: -if( xxa < 0.0 ) - { - cc = -cc; - ss = -ss; - } - -*cca = cc; -*ssa = ss; -#if !ANSIC -return 0; -#endif -} |