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C
C     ..................................................................
C
C        SUBROUTINE KOLM2
C
C        PURPOSE
C
C           TESTS THE DIFFERENCE BETWEEN TWO SAMPLE DISTRIBUTION
C           FUNCTIONS USING THE KOLMOGOROV-SMIRNOV TEST
C
C        USAGE
C           CALL KOLM2(X,Y,N,M,Z,PROB)
C
C        DESCRIPTION OF PARAMETERS
C           X    - INPUT VECTOR OF N INDEPENDENT OBSERVATIONS.  ON
C                  RETURN FROM KOLM2, X HAS BEEN SORTED INTO A
C                  MONOTONIC NON-DECREASING SEQUENCE.
C           Y    - INPUT VECTOR OF M INDEPENDENT OBSERVATIONS.  ON
C                  RETURN FROM KOLM2, Y HAS BEEN SORTED INTO A
C                  MONOTONIC NON-DECREASING SEQUENCE.
C           N    - NUMBER OF OBSERVATIONS IN X
C           M    - NUMBER OF OBSERVATIONS IN Y
C           Z    - OUTPUT VARIABLE CONTAINING THE GREATEST VALUE WITH
C                  RESPECT TO THE SPECTRUM OF X AND Y OF
C                  SQRT((M*N)/(M+N))*ABS(FN(X)-GM(Y)) WHERE
C                  FN(X) IS THE EMPIRICAL DISTRIBUTION FUNCTION OF THE
C                  SET (X) AND GM(Y) IS THE EMPIRICAL DISTRIBUTION
C                  FUNCTION OF THE SET (Y).
C           PROB - OUTPUT VARIABLE CONTAINING THE PROBABILITY OF
C                  THE STATISTIC BEING GREATER THAN OR EQUAL TO Z IF
C                  THE HYPOTHESIS THAT X AND Y ARE FROM THE SAME PDF IS
C                  TRUE.  E.G., PROB= 0.05 IMPLIES THAT ONE CAN REJECT
C                  THE NULL HYPOTHESIS THAT THE SETS X AND Y ARE FROM
C                  THE SAME DENSITY WITH 5 PER CENT PROBABILITY OF BEING
C                  INCORRECT.  PROB = 1. - SMIRN(Z).
C
C        REMARKS
C           N AND M SHOULD BE GREATER THAN OR EQUAL TO 100.  (SEE THE
C           MATHEMATICAL DESCRIPTION FOR THIS SUBROUTINE AND FOR THE
C           SUBROUTINE SMIRN, CONCERNING ASYMPTOTIC FORMULAE).
C
C           DOUBLE PRECISION USAGE---IT IS DOUBTFUL THAT THE USER WILL
C           WISH TO PERFORM THIS TEST USING DOUBLE PRECISION ACCURACY.
C           IF ONE WISHES TO COMMUNICATE WITH KOLM2 IN A DOUBLE
C           PRECISION PROGRAM, HE SHOULD CALL THE FORTRAN SUPPLIED
C           PROGRAM SNGL(X) PRIOR TO CALLING KOLM2, AND CALL THE
C           FORTRAN SUPPLIED PROGRAM DBLE(X) AFTER EXITING FROM KOLM2.
C           (NOTE THAT SUBROUTINE SMIRN DOES HAVE DOUBLE PRECISION
C           CAPABILITY AS SUPPLIED BY THIS PACKAGE.)
C
C
C        SUBROUTINES AND FUNCTION SUBPROGRAMS REQUIRED
C           SMIRN
C
C        METHOD
C           FOR REFERENCE, SEE (1) W. FELLER--ON THE KOLMOGOROV-SMIRNOV
C           LIMIT THEOREMS FOR EMPIRICAL DISTRIBUTIONS--
C           ANNALS OF MATH. STAT., 19, 1948.  177-189,
C           (2) N. SMIRNOV--TABLE FOR ESTIMATING THE GOODNESS OF FIT
C           OF EMPIRICAL DISTRIBUTIONS--ANNALS OF MATH. STAT., 19,
C           1948.  279-281.
C           (3) R. VON MISES--MATHEMATICAL THEORY OF PROBABILITY AND
C           STATISTICS--ACADEMIC PRESS, NEW YORK, 1964.  490-493,
C           (4) B.V. GNEDENKO--THE THEORY OF PROBABILITY--CHELSEA
C           PUBLISHING COMPANY, NEW YORK, 1962.  384-401.
C
C     ..................................................................
C
      SUBROUTINE KOLM2(X,Y,N,M,Z,PROB)
      DIMENSION X(1),Y(1)
C
C        SORT X INTO ASCENDING SEQUENCE
C
      DO 5 I=2,N
      IF(X(I)-X(I-1))1,5,5
    1 TEMP=X(I)
      IM=I-1
      DO 3 J=1,IM
      L=I-J
      IF(TEMP-X(L))2,4,4
    2 X(L+1)=X(L)
    3 CONTINUE
      X(1)=TEMP
      GO TO 5
    4 X(L+1)=TEMP
    5 CONTINUE
C
C        SORT Y INTO ASCENDING SEQUENCE
C
      DO 10 I=2,M
      IF(Y(I)-Y(I-1))6,10,10
    6 TEMP=Y(I)
      IM=I-1
      DO 8  J=1,IM
      L=I-J
      IF(TEMP-Y(L))7,9,9
    7 Y(L+1)=Y(L)
    8 CONTINUE
      Y(1)=TEMP
      GO TO 10
    9 Y(L+1)=TEMP
   10 CONTINUE
C
C        CALCULATE D = ABS(FN-GM) OVER THE SPECTRUM OF X AND Y
C
      XN=FLOAT(N)
      XN1=1./XN
      XM=FLOAT(M)
      XM1=1./XM
      D=0.0
      I=0
      J=0
      K=0
      L=0
   11 IF(X(I+1)-Y(J+1))12,13,18
   12 K=1
      GO TO 14
   13 K=0
   14 I=I+1
      IF(I-N)15,21,21
   15 IF(X(I+1)-X(I))14,14,16
   16 IF(K)17,18,17
C
C        CHOOSE THE MAXIMUM DIFFERENCE, D
C
   17 D=AMAX1(D,ABS(FLOAT(I)*XN1-FLOAT(J)*XM1))
      IF(L)22,11,22
   18 J=J+1
      IF(J-M)19,20,20
   19 IF(Y(J+1)-Y(J))18,18,17
   20 L=1
      GO TO 17
   21 L=1
      GO TO 16
C
C        CALCULATE THE STATISTIC Z
C
   22 Z=D*SQRT((XN*XM)/(XN+XM))
C
C        CALCULATE THE PROBABILITY ASSOCIATED WITH Z
C
      CALL SMIRN(Z,PROB)
      PROB=1.0-PROB
      RETURN
      END