      SUBROUTINE LGNCDF(X,CDF)
C
C     PURPOSE--THIS SUBROUTINE COMPUTES THE CUMULATIVE DISTRIBUTION
C              FUNCTION VALUE FOR THE LOGNORMAL
C              DISTRIBUTION.
C              THE LOGNORMAL DISTRIBUTION USED
C              HEREIN HAS MEAN = SQRT(E) = 1.64872127
C              AND STANDARD DEVIATION = SQRT(E*(E-1)) = 2.16119742.
C              THIS DISTRIBUTION IS DEFINED FOR ALL POSITIVE X
C              AND HAS THE PROBABILITY DENSITY FUNCTION
C              F(X) = (1/(X*SQRT(2*PI))) * EXP(-ALOG(X)*ALOG(X)/2)
C              THE LOGNORMAL DISTRIBUTION USED HEREIN
C              IS THE DISTRIBUTION OF THE VARIATE X = EXP(Z) WHERE
C              THE VARIATE Z IS NORMALLY DISTRIBUTED
C              WITH MEAN = 0 AND STANDARD DEVIATION = 1.
C     INPUT  ARGUMENTS--X      = THE SINGLE PRECISION VALUE 
C                                AT WHICH THE CUMULATIVE DISTRIBUTION 
C                                FUNCTION IS TO BE EVALUATED.
C                                X SHOULD BE POSITIVE.
C     OUTPUT ARGUMENTS--CDF    = THE SINGLE PRECISION CUMULATIVE
C                                DISTRIBUTION FUNCTION VALUE.
C     OUTPUT--THE SINGLE PRECISION CUMULATIVE DISTRIBUTION
C             FUNCTION VALUE CDF FOR THE LOGNORMAL
C             DISTRIBUTION WITH MEAN = SQRT(E) = 1.64872127 
C             AND STANDARD DEVIATION = SQRT(E*(E-1)) = 2.16119742.
C     PRINTING--NONE UNLESS AN INPUT ARGUMENT ERROR CONDITION EXISTS. 
C     RESTRICTIONS--X SHOULD BE POSITIVE.
C     OTHER DATAPAC   SUBROUTINES NEEDED--NORCDF. 
C     FORTRAN LIBRARY SUBROUTINES NEEDED--ALOG.
C     MODE OF INTERNAL OPERATIONS--SINGLE PRECISION.
C     LANGUAGE--ANSI FORTRAN. 
C     REFERENCES--JOHNSON AND KOTZ, CONTINUOUS UNIVARIATE
C                 DISTRIBUTIONS--1, 1970, PAGES 112-136.
C               --CRAMER, MATHEMATICAL METHODS OF STATISTICS,
C                 1946, PAGES 219-220.
C     WRITTEN BY--JAMES J. FILLIBEN
C                 STATISTICAL ENGINEERING LABORATORY (205.03)
C                 NATIONAL BUREAU OF STANDARDS
C                 WASHINGTON, D. C. 20234
C                 PHONE:  301-921-2315
C     ORIGINAL VERSION--NOVEMBER  1975. 
C
C---------------------------------------------------------------------
C
      IPR=6
C
C     CHECK THE INPUT ARGUMENTS FOR ERRORS
C
      IF(X.LE.0.0)GOTO50
      GOTO90
   50 WRITE(IPR,4)
      WRITE(IPR,46)X
      CDF=0.0
      RETURN
   90 CONTINUE
    4 FORMAT(1H ,100H***** NON-FATAL DIAGNOSTIC--THE FIRST  INPUT ARGUME
     1NT TO THE LGNCDF SUBROUTINE IS NON-POSITIVE *****)
   46 FORMAT(1H , 35H***** THE VALUE OF THE ARGUMENT IS ,E15.8,6H *****)
C
C-----START POINT-----------------------------------------------------
C
      ARG=ALOG(X)
      CALL NORCDF(ARG,CDF)
C
      RETURN
      END 
