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| Rev | Author | Line No. | Line |
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| 4349 | Serge | 1 | |
| 2 | /* |
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| 3 | * ==================================================== |
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| 4 | * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
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| 5 | * |
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| 6 | * Developed at SunPro, a Sun Microsystems, Inc. business. |
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| 7 | * Permission to use, copy, modify, and distribute this |
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| 8 | * software is freely granted, provided that this notice |
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| 9 | * is preserved. |
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| 10 | * ==================================================== |
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| 11 | * |
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| 12 | */ |
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| 13 | |||
| 14 | |||
| 15 | * Return the logarithm of the Gamma function of x. |
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| 16 | * |
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| 17 | * Method: call __ieee754_lgamma_r |
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| 18 | */ |
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| 19 | |||
| 20 | |||
| 21 | #include |
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| 22 | #include |
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| 23 | |||
| 24 | |||
| 25 | |||
| 26 | |||
| 27 | double lgamma(double x) |
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| 28 | #else |
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| 29 | double lgamma(x) |
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| 30 | double x; |
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| 31 | #endif |
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| 32 | { |
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| 33 | #ifdef _IEEE_LIBM |
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| 34 | return __ieee754_lgamma_r(x,&(_REENT_SIGNGAM(_REENT))); |
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| 35 | #else |
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| 36 | double y; |
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| 37 | struct exception exc; |
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| 38 | y = __ieee754_lgamma_r(x,&(_REENT_SIGNGAM(_REENT))); |
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| 39 | if(_LIB_VERSION == _IEEE_) return y; |
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| 40 | if(!finite(y)&&finite(x)) { |
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| 41 | #ifndef HUGE_VAL |
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| 42 | #define HUGE_VAL inf |
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| 43 | double inf = 0.0; |
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| 44 | |||
| 45 | |||
| 46 | #endif |
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| 47 | exc.name = "lgamma"; |
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| 48 | exc.err = 0; |
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| 49 | exc.arg1 = x; |
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| 50 | exc.arg2 = x; |
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| 51 | if (_LIB_VERSION == _SVID_) |
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| 52 | exc.retval = HUGE; |
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| 53 | else |
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| 54 | exc.retval = HUGE_VAL; |
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| 55 | if(floor(x)==x&&x<=0.0) { |
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| 56 | /* lgamma(-integer) */ |
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| 57 | exc.type = SING; |
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| 58 | if (_LIB_VERSION == _POSIX_) |
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| 59 | errno = EDOM; |
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| 60 | else if (!matherr(&exc)) { |
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| 61 | errno = EDOM; |
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| 62 | } |
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| 63 | |||
| 64 | |||
| 65 | /* lgamma(finite) overflow */ |
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| 66 | exc.type = OVERFLOW; |
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| 67 | if (_LIB_VERSION == _POSIX_) |
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| 68 | errno = ERANGE; |
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| 69 | else if (!matherr(&exc)) { |
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| 70 | errno = ERANGE; |
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| 71 | } |
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| 72 | } |
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| 73 | if (exc.err != 0) |
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| 74 | errno = exc.err; |
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| 75 | return exc.retval; |
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| 76 | } else |
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| 77 | return y; |
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| 78 | #endif |
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| 79 | } |
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| 80 | |||
| 81 | |||
| 82 |