*     G01FTF Example Program Text
*     Mark 21 Release. NAG Copyright 2004.
*     .. Parameters ..
      INTEGER          NIN, NOUT
      PARAMETER        (NIN=5,NOUT=6)
*     .. Local Scalars ..
      DOUBLE PRECISION X, Y
      INTEGER          IFAIL
*     .. External Functions ..
      DOUBLE PRECISION G01FTF
      EXTERNAL         G01FTF
*     .. Executable Statements ..
      WRITE (NOUT,*) 'G01FTF Example Program Results'
*     Skip heading in data file
      READ (NIN,*)
      WRITE (NOUT,*)
      WRITE (NOUT,*) '  X          Y        IFAIL'
      WRITE (NOUT,*)
   20 READ (NIN,*,END=40) X
*
*     Compute the value of the inverse of the Landau distribution function
*
      IFAIL = 1
*
      Y = G01FTF(X,IFAIL)
*
      IF (IFAIL.GE.0) THEN
         WRITE (NOUT,99999) X, Y, IFAIL
         GO TO 20
      ELSE
         WRITE (NOUT,99998) ' ** G01FTF returned with IFAIL = ', IFAIL
      END IF
   40 CONTINUE
*
99999 FORMAT (1X,F4.1,3X,1P,E12.4,I6)
99998 FORMAT (1X,A,I5)
      END