TGAMMA(3) BSD Library Functions Manual TGAMMA(3)

NAME
     ttggaammmmaa, llggaammmmaa, ggaammmmaa - gamma and log of gamma

SYNOPSIS
     ##iinncclluuddee <>

     double
     ttggaammmmaa(double x);

     long double
     ttggaammmmaall(long double x);

     float
     ttggaammmmaaff(float x);

     double
     llggaammmmaa(double x);

     long double
     llggaammmmaall(long double x);

     float
     llggaammmmaaff(float x);

     double
     ggaammmmaa(double x);

DESCRIPTION
     ttggaammmmaa() calculates the gamma function of x.  llggaammmmaa() calculates the
     natural logorithm of the absolute value of the gamma function of x.
     ggaammmmaa() is the same function as tgamma. Its use is deprecated.

SSPPEECCIIAALL VVAALLUUEESS
     ttggaammmmaa(+-0) returns +-infinity and raises the "divide-by-zero" floating-
     point exception.

     ttggaammmmaa(x) returns a NaN and raises the "invalid" floating-point exception
     if x is a negative integer.

     ttggaammmmaa(-infinity) returns a NaN and raises the "invalid" floating-point
     exception.

     ttggaammmmaa(+infinity) returns +infinity.

     ttggaammmmaa(x) generates a domain error if x is a negative integer or if the
     result cannnot be respresented when x is 0.

     A range error may occur if the magnitude of x is too large or too small.

     ggaammmmaa() has the same behavior as ttggaammmmaa().

     llggaammmmaa(1) returns +0.

     llggaammmmaa(2) returns +0.

     llggaammmmaa(x) returns +infinity and raises the "divide-by-zero" floating-
     point exception if x is a negative integer or 0.

     llggaammmmaa(+-infinity) returns +infinity.

     llggaammmmaa(x) generates a range error if x is too large.

     A range error may occur if x is a negative integer or 0.

NNOOTTEE
     llggaammmmaa(x) and its variants have the (non-threadsafe) side-effect of set-
     ting the global variable signgam to +-1, equal to the sign of ttggaammmmaa(x).

SEE ALSO
     math(3)

STANDARDS     The ttggaammmmaa() , and llggaammmmaa() functions conform to ISO/IEC 9899:1999(E).

                                  Oct 9, 2006