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Diffstat (limited to 'newlib/libm/math/w_gamma.c')
| -rw-r--r-- | newlib/libm/math/w_gamma.c | 193 |
1 files changed, 0 insertions, 193 deletions
diff --git a/newlib/libm/math/w_gamma.c b/newlib/libm/math/w_gamma.c deleted file mode 100644 index 358a493df..000000000 --- a/newlib/libm/math/w_gamma.c +++ /dev/null @@ -1,193 +0,0 @@ - -/* @(#)w_gamma.c 5.1 93/09/24 */ -/* - * ==================================================== - * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. - * - * Developed at SunPro, a Sun Microsystems, Inc. business. - * Permission to use, copy, modify, and distribute this - * software is freely granted, provided that this notice - * is preserved. - * ==================================================== - * - */ - -/* -FUNCTION - <<gamma>>, <<gammaf>>, <<lgamma>>, <<lgammaf>>, <<gamma_r>>, - <<gammaf_r>>, <<lgamma_r>>, <<lgammaf_r>>---logarithmic gamma - function -INDEX -gamma -INDEX -gammaf -INDEX -lgamma -INDEX -lgammaf -INDEX -gamma_r -INDEX -gammaf_r -INDEX -lgamma_r -INDEX -lgammaf_r - -ANSI_SYNOPSIS -#include <math.h> -double gamma(double <[x]>); -float gammaf(float <[x]>); -double lgamma(double <[x]>); -float lgammaf(float <[x]>); -double gamma_r(double <[x]>, int *<[signgamp]>); -float gammaf_r(float <[x]>, int *<[signgamp]>); -double lgamma_r(double <[x]>, int *<[signgamp]>); -float lgammaf_r(float <[x]>, int *<[signgamp]>); - -TRAD_SYNOPSIS -#include <math.h> -double gamma(<[x]>) -double <[x]>; -float gammaf(<[x]>) -float <[x]>; -double lgamma(<[x]>) -double <[x]>; -float lgammaf(<[x]>) -float <[x]>; -double gamma_r(<[x]>, <[signgamp]>) -double <[x]>; -int <[signgamp]>; -float gammaf_r(<[x]>, <[signgamp]>) -float <[x]>; -int <[signgamp]>; -double lgamma_r(<[x]>, <[signgamp]>) -double <[x]>; -int <[signgamp]>; -float lgammaf_r(<[x]>, <[signgamp]>) -float <[x]>; -int <[signgamp]>; - -DESCRIPTION -<<gamma>> calculates -@tex -$\mit ln\bigl(\Gamma(x)\bigr)$, -@end tex -the natural logarithm of the gamma function of <[x]>. The gamma function -(<<exp(gamma(<[x]>))>>) is a generalization of factorial, and retains -the property that -@ifinfo -<<exp(gamma(N))>> is equivalent to <<N*exp(gamma(N-1))>>. -@end ifinfo -@tex -$\mit \Gamma(N)\equiv N\times\Gamma(N-1)$. -@end tex -Accordingly, the results of the gamma function itself grow very -quickly. <<gamma>> is defined as -@tex -$\mit ln\bigl(\Gamma(x)\bigr)$ rather than simply $\mit \Gamma(x)$ -@end tex -@ifinfo -the natural log of the gamma function, rather than the gamma function -itself, -@end ifinfo -to extend the useful range of results representable. - -The sign of the result is returned in the global variable <<signgam>>, -which is declared in math.h. - -<<gammaf>> performs the same calculation as <<gamma>>, but uses and -returns <<float>> values. - -<<lgamma>> and <<lgammaf>> are alternate names for <<gamma>> and -<<gammaf>>. The use of <<lgamma>> instead of <<gamma>> is a reminder -that these functions compute the log of the gamma function, rather -than the gamma function itself. - -The functions <<gamma_r>>, <<gammaf_r>>, <<lgamma_r>>, and -<<lgammaf_r>> are just like <<gamma>>, <<gammaf>>, <<lgamma>>, and -<<lgammaf>>, respectively, but take an additional argument. This -additional argument is a pointer to an integer. This additional -argument is used to return the sign of the result, and the global -variable <<signgam>> is not used. These functions may be used for -reentrant calls (but they will still set the global variable <<errno>> -if an error occurs). - -RETURNS -Normally, the computed result is returned. - -When <[x]> is a nonpositive integer, <<gamma>> returns <<HUGE_VAL>> -and <<errno>> is set to <<EDOM>>. If the result overflows, <<gamma>> -returns <<HUGE_VAL>> and <<errno>> is set to <<ERANGE>>. - -You can modify this error treatment using <<matherr>>. - -PORTABILITY -Neither <<gamma>> nor <<gammaf>> is ANSI C. */ - -/* double gamma(double x) - * Return the logarithm of the Gamma function of x. - * - * Method: call gamma_r - */ - -#include "fdlibm.h" -#include <reent.h> -#include <errno.h> - -#ifndef _DOUBLE_IS_32BITS - -#ifdef __STDC__ - double gamma(double x) -#else - double gamma(x) - double x; -#endif -{ -#ifdef _IEEE_LIBM - return __ieee754_gamma_r(x,&(_REENT_SIGNGAM(_REENT))); -#else - double y; - struct exception exc; - y = __ieee754_gamma_r(x,&(_REENT_SIGNGAM(_REENT))); - if(_LIB_VERSION == _IEEE_) return y; - if(!finite(y)&&finite(x)) { -#ifndef HUGE_VAL -#define HUGE_VAL inf - double inf = 0.0; - - SET_HIGH_WORD(inf,0x7ff00000); /* set inf to infinite */ -#endif - exc.name = "gamma"; - exc.err = 0; - exc.arg1 = exc.arg2 = x; - if (_LIB_VERSION == _SVID_) - exc.retval = HUGE; - else - exc.retval = HUGE_VAL; - if(floor(x)==x&&x<=0.0) { - /* gamma(-integer) or gamma(0) */ - exc.type = SING; - if (_LIB_VERSION == _POSIX_) - errno = EDOM; - else if (!matherr(&exc)) { - errno = EDOM; - } - } else { - /* gamma(finite) overflow */ - exc.type = OVERFLOW; - if (_LIB_VERSION == _POSIX_) - errno = ERANGE; - else if (!matherr(&exc)) { - errno = ERANGE; - } - } - if (exc.err != 0) - errno = exc.err; - return exc.retval; - } else - return y; -#endif -} - -#endif /* defined(_DOUBLE_IS_32BITS) */ |