개요

• 솔라나라에 설명된 어플리케이션에 대해 맨 페이지를 찾아 출력한다.
• MAN 페이지에 대한 설명은 윈디하나의 솔라나라: MAN 페이지을 참고하자.
• svcadm(1M)을 검색하려면 섹션에서 1M 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.

lgamma(3m)

Mathematical Library Functions                                      lgamma(3M)



NAME
       lgamma,  lgammaf,  lgammal, lgamma_r, lgammaf_r, lgammal_r, gamma, gam‐
       maf, gammal, gamma_r, gammaf_r, gammal_r - log gamma function

SYNOPSIS
       c99 [ flag... ] file... -lm [ library... ]
       #include <math.h>

       extern int signgam;

       double lgamma(double x);


       float lgammaf(float x);


       long double lgammal(long double x);


       double gamma(double x);


       float gammaf(float x);


       long double gammal(long double x);


       double lgamma_r(double x, int *signgamp);


       float lgammaf_r(float x, int *signgamp);


       long double lgammal_r(long double x, int *signgamp);


       double gamma_r(double x, int *signgamp);


       float gammaf_r(float x, int *signgamp);


       long double gammal_r(long double x, int *signgamp);

DESCRIPTION
       These functions return


       ln||~(x)|.sp

       where


       |~(x) = integral from 0 to +Infinity of pow(t,x-1)*exp(-t) dt.sp

       for x > 0 and


       |~(x) = n/(|~(1-x)sin(nx)).sp

       for x < 1.


       These functions use the external integer signgam to return the sign  of
       |~(x)  while  lgamma_r()  and  gamma_r()  use  the user-allocated space
       addressed by signgamp.

RETURN VALUES
       Upon successful completion,  these  functions  return  the  logarithmic
       gamma of x.


       If x is a non-positive integer, a pole error occurs and these functions
       return +HUGE_VAL, +HUGE_VALF, and +HUGE_VALL, respectively.


       If x is NaN, a NaN is returned.


       If x is 1 or 2, +0 shall be returned.


       If x is ±Inf, +Inf is returned.

ERRORS
       These functions will fail if:

       Pole Error    The x argument is a negative integer or 0.

                     If the integer expression (math_errhandling & MATH_ERREX‐
                     CEPT) is non-zero, then the divide-by-zero floating-point
                     exception is raised.


USAGE
       An application wanting to check for exceptions should  call  feclearex‐
       cept(FE_ALL_EXCEPT)  before  calling  these  functions.  On  return, if
       fetestexcept(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is
       non-zero,  an  exception  has been raised. An application should either
       examine the return value or check the floating point exception flags to
       detect exceptions.


       In    the    case    of   lgamma(),   do   not   use   the   expression
       signgam*exp(lgamma(x)) to compute


       `g := |~(x)'.sp

       Instead compute lgamma() first:


       lg = lgamma(x); g = signgam*exp(lg);


       only after lgamma() has returned can  signgam  be  correct.  Note  that
       |~(x)  must overflow when x is large enough, underflow when −x is large
       enough, and generate a division by 0 exception at the singularities x a
       nonpositive integer.

ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i)


       ATTRIBUTE  TYPEATTRIBUTE  VALUE _ Interface StabilityCommitted _ Avail‐
       abilitysystem/library/math _ MT-LevelSee below.  _ StandardSee below.



       The lgamma(), lgammaf(), lgammal(),  gamma(),  gammaf(),  and  gammal()
       functions  are  Unsafe  in  multithreaded applications. The lgamma_r(),
       lgammaf_r(), lgammal_r(), gamma_r(), gammaf_r(), and  gammal_r()  func‐
       tions are MT-Safe and should be used instead.


       For lgamma(), lgammaf(), lgammal(), and gamma(), see standards(7).

SEE ALSO
       math.h(3HEAD), exp(3M), feclearexcept(3M), fetestexcept(3M), isnan(3M),
       attributes(7), standards(7)



Solaris 11.4                     27 Sept 2016                       lgamma(3M)