1 #include <float.h>
2 #include "__invtrigl.h"
3
4 #if LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
5 static const long double
6 pS0 = 1.66666666666666666631e-01L,
7 pS1 = -4.16313987993683104320e-01L,
8 pS2 = 3.69068046323246813704e-01L,
9 pS3 = -1.36213932016738603108e-01L,
10 pS4 = 1.78324189708471965733e-02L,
11 pS5 = -2.19216428382605211588e-04L,
12 pS6 = -7.10526623669075243183e-06L,
13 qS1 = -2.94788392796209867269e+00L,
14 qS2 = 3.27309890266528636716e+00L,
15 qS3 = -1.68285799854822427013e+00L,
16 qS4 = 3.90699412641738801874e-01L,
17 qS5 = -3.14365703596053263322e-02L;
18
19 const long double pio2_hi = 1.57079632679489661926L;
20 const long double pio2_lo = -2.50827880633416601173e-20L;
21
22 /* used in asinl() and acosl() */
23 /* R(x^2) is a rational approximation of (asin(x)-x)/x^3 with Remez algorithm */
__invtrigl_R(long double z)24 long double __invtrigl_R(long double z)
25 {
26 long double p, q;
27 p = z*(pS0+z*(pS1+z*(pS2+z*(pS3+z*(pS4+z*(pS5+z*pS6))))));
28 q = 1.0+z*(qS1+z*(qS2+z*(qS3+z*(qS4+z*qS5))));
29 return p/q;
30 }
31 #elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
32 static const long double
33 pS0 = 1.66666666666666666666666666666700314e-01L,
34 pS1 = -7.32816946414566252574527475428622708e-01L,
35 pS2 = 1.34215708714992334609030036562143589e+00L,
36 pS3 = -1.32483151677116409805070261790752040e+00L,
37 pS4 = 7.61206183613632558824485341162121989e-01L,
38 pS5 = -2.56165783329023486777386833928147375e-01L,
39 pS6 = 4.80718586374448793411019434585413855e-02L,
40 pS7 = -4.42523267167024279410230886239774718e-03L,
41 pS8 = 1.44551535183911458253205638280410064e-04L,
42 pS9 = -2.10558957916600254061591040482706179e-07L,
43 qS1 = -4.84690167848739751544716485245697428e+00L,
44 qS2 = 9.96619113536172610135016921140206980e+00L,
45 qS3 = -1.13177895428973036660836798461641458e+01L,
46 qS4 = 7.74004374389488266169304117714658761e+00L,
47 qS5 = -3.25871986053534084709023539900339905e+00L,
48 qS6 = 8.27830318881232209752469022352928864e-01L,
49 qS7 = -1.18768052702942805423330715206348004e-01L,
50 qS8 = 8.32600764660522313269101537926539470e-03L,
51 qS9 = -1.99407384882605586705979504567947007e-04L;
52
53 const long double pio2_hi = 1.57079632679489661923132169163975140L;
54 const long double pio2_lo = 4.33590506506189051239852201302167613e-35L;
55
__invtrigl_R(long double z)56 long double __invtrigl_R(long double z)
57 {
58 long double p, q;
59 p = z*(pS0+z*(pS1+z*(pS2+z*(pS3+z*(pS4+z*(pS5+z*(pS6+z*(pS7+z*(pS8+z*pS9)))))))));
60 q = 1.0+z*(qS1+z*(qS2+z*(qS3+z*(qS4+z*(qS5+z*(qS6+z*(qS7+z*(qS8+z*qS9))))))));
61 return p/q;
62 }
63 #endif
64