# dfac.f

          DOUBLE PRECISION FUNCTION DFAC (N)
    C***BEGIN PROLOGUE  DFAC
    C***PURPOSE  Compute the factorial function.
    C***LIBRARY   SLATEC (FNLIB)
    C***CATEGORY  C1
    C***TYPE      DOUBLE PRECISION (FAC-S, DFAC-D)
    C***KEYWORDS  FACTORIAL, FNLIB, SPECIAL FUNCTIONS
    C***AUTHOR  Fullerton, W., (LANL)
    C***DESCRIPTION
    C
    C DFAC(N) calculates the double precision factorial for integer
    C argument N.
    C
    C***REFERENCES  (NONE)
    C***ROUTINES CALLED  D9LGMC, DGAMLM, XERMSG
    C***REVISION HISTORY  (YYMMDD)
    C   770601  DATE WRITTEN
    C   890531  Changed all specific intrinsics to generic.  (WRB)
    C   890531  REVISION DATE from Version 3.2
    C   891214  Prologue converted to Version 4.0 format.  (BAB)
    C   900315  CALLs to XERROR changed to CALLs to XERMSG.  (THJ)
    C***END PROLOGUE  DFAC