Esope source files

   1 : C GAMMAF    SOURCE    CHAT      05/01/13    00:15:29     5004           
   2 :       FUNCTION GAMMAF (X)
   3 :       IMPLICIT INTEGER(I-N)
   4 :       IMPLICIT REAL*8 (A-H,O-Z)
   5 :       ZERO = 0.0D0
   6 :       HALF = 0.5D0
   7 :       ONE  = 1.0D0
   8 :       TWO  = 2.0D0
   9 :       FOUR = 4.0D0
  10 :       PI   = FOUR*DATAN(ONE)
  11 :       GAMMAF = ONE
  12 :       IF (X.EQ.-HALF) GAMMAF = -TWO*DSQRT(PI)
  13 :       IF (X.EQ. HALF) GAMMAF =  DSQRT(PI)
  14 :       IF (X.EQ. ONE ) GAMMAF =  ONE
  15 :       IF (X.EQ. TWO ) GAMMAF =  ONE
  16 :       IF (X.EQ. 1.5D0) GAMMAF =  DSQRT(PI)/2.D0
  17 :       IF (X.EQ. 2.5D0) GAMMAF =  1.5D0*DSQRT(PI)/2.D0
  18 :       IF (X.EQ. 3.5D0) GAMMAF =  2.5D0*1.5D0*DSQRT(PI)/2.D0
  19 :       IF (X.EQ. 3.D0 ) GAMMAF =  2.D0
  20 :       IF (X.EQ. 4.D0 ) GAMMAF = 6.D0
  21 :       IF (X.EQ. 5.D0 ) GAMMAF = 24.D0
  22 :       IF (X.EQ. 6.D0 ) GAMMAF = 120.D0
  23 :       RETURN
  24 :       END
  25 :  
  26 :