Description

   lgamma() returns the logarithm of the absolute value of gamma
   of x, or ln(|G(x)|), where G is the gamma function. The sign of
   gamma of x is returned in the external integer variable signgam
   as +1 or -1. The x parameter cannot be 0 or a negative integer.

   gamma() returns the natural log of the gamma function and so is
   functionally equivalent to lgamma(). Because of this, gamma()  is
   marked TO BE WITHDRAWN in the X/Open Portability Guide, Revision
   4 (XPG4).


                          Entry-Point Names

   Generic
   Function   Data Type   OpenVMS                Tru64 UNIX
   Name       Required

   lgamma     S_FLOAT     math$lgamma_s          lgammaf
              T_FLOAT     math$lgamma_t          lgamma
              X_FLOAT     math$lgamma_x          lgammal
              F_FLOAT     math$lgamma_f
              G_FLOAT     math$lgamma_g