diff options
author | PikalaxALT <pikalaxalt@gmail.com> | 2017-12-15 09:38:53 -0500 |
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committer | PikalaxALT <pikalaxalt@gmail.com> | 2017-12-15 09:39:34 -0500 |
commit | f95a4a932476be2ba99e2fd081e8d2bc6ea12813 (patch) | |
tree | 75f67192cb2d7b7b575c94edda318e475239b63c /newlib/libm/mathfp/sf_asine.c | |
parent | f60aca96985e68c7d8a52eb7bc955fb80e132f73 (diff) |
Import newlib and create makefile
Diffstat (limited to 'newlib/libm/mathfp/sf_asine.c')
-rw-r--r-- | newlib/libm/mathfp/sf_asine.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/newlib/libm/mathfp/sf_asine.c b/newlib/libm/mathfp/sf_asine.c new file mode 100644 index 0000000..12ba289 --- /dev/null +++ b/newlib/libm/mathfp/sf_asine.c @@ -0,0 +1,105 @@ + +/* @(#)z_asinef.c 1.0 98/08/13 */ +/****************************************************************** + * The following routines are coded directly from the algorithms + * and coefficients given in "Software Manual for the Elementary + * Functions" by William J. Cody, Jr. and William Waite, Prentice + * Hall, 1980. + ******************************************************************/ +/****************************************************************** + * Arcsine + * + * Input: + * x - floating point value + * acosine - indicates acos calculation + * + * Output: + * Arcsine of x. + * + * Description: + * This routine calculates arcsine / arccosine. + * + *****************************************************************/ + +#include "fdlibm.h" +#include "zmath.h" + +static const float p[] = { 0.933935835, -0.504400557 }; +static const float q[] = { 0.560363004e+1, -0.554846723e+1 }; +static const float a[] = { 0.0, 0.785398163 }; +static const float b[] = { 1.570796326, 0.785398163 }; + +float +_DEFUN (asinef, (float, int), + float x _AND + int acosine) +{ + int flag, i; + int branch = 0; + float g, res, R, P, Q, y; + + /* Check for special values. */ + i = numtestf (x); + if (i == NAN || i == INF) + { + errno = EDOM; + if (i == NAN) + return (x); + else + return (z_infinity_f.f); + } + + y = fabsf (x); + flag = acosine; + + if (y > 0.5) + { + i = 1 - flag; + + /* Check for range error. */ + if (y > 1.0) + { + errno = ERANGE; + return (z_notanum_f.f); + } + + g = (1 - y) / 2.0; + y = -2 * sqrt (g); + branch = 1; + } + else + { + i = flag; + if (y < z_rooteps_f) + res = y; + else + g = y * y; + } + + if (y >= z_rooteps_f || branch == 1) + { + /* Calculate the Taylor series. */ + P = (p[1] * g + p[0]) * g; + Q = (g + q[1]) * g + q[0]; + R = P / Q; + + res = y + y * R; + } + + /* Calculate asine or acose. */ + if (flag == 0) + { + res = (a[i] + res) + a[i]; + if (x < 0.0) + res = -res; + } + else + { + if (x < 0.0) + res = (b[i] + res) + b[i]; + else + res = (a[i] - res) + a[i]; + } + + return (res); +} |