SUBROUTINE LORFM (XL,YL,SIDEX,SIDEY,NITER,COL,MCPAX,MCPAY)
C
C     COPYRIGHT (C) 1985-1992 BY ART MATRIX.  ALL RIGHTS RESERVED.
C
C***********************************************************************
C***********************************************************************
C
      IMPLICIT REAL*8 (A-H,O-Z)
C
         REAL*8 M1, M2, M3, M4
C
      INTEGER*4 COL(0:MCPAX,0:MCPAY)
C
      DIMENSION X(3),T(3),M1(3),M2(3),M3(3),M4(3)
C
C***********************************************************************
C***********************************************************************
C
      CALL DRVID ('FM      ',104,2,12,1)
C
C***********************************************************************
C***********************************************************************
C
      DO 7 J = 0,MCPAY
      DO 7 I = 0,MCPAX
7     COL(I,J) = 0
C
      CPUX = MCPAX/SIDEX
      CPUY = MCPAY/SIDEY
C
      A  =  10
      C  =  8./3.
      B  =  28
C     H  = .0001
      H  = .001
C
C      X(1) = 0.1
C      X(2) = 0.1
C      X(3) = 0.1
       X(1) = 0.00001
       X(2) = 0.00001
       X(3) = 0.00001
C
C***********************************************************************
C***********************************************************************
C
      DO 1000 I = 1,NITER
C
         CALL LORFUN (X,M1,A,B,C,H)
C
         T(1) = X(1) + M1(1)/2
         T(2) = X(2) + M1(2)/2
         T(3) = X(3) + M1(3)/2
         CALL LORFUN (T,M2,A,B,C,H)
C
         T(1) = X(1) + M2(1)/2
         T(2) = X(2) + M2(2)/2
         T(3) = X(3) + M2(3)/2
         CALL LORFUN (T,M3,A,B,C,H)
C
         T(1) = X(1) + M3(1)
         T(2) = X(2) + M3(2)
         T(3) = X(3) + M3(3)
         CALL LORFUN (T,M4,A,B,C,H)
C
         X(1) = X(1) + (M1(1) + 2*M2(1) + 2*M3(1) + M4(1))/6
         X(2) = X(2) + (M1(2) + 2*M2(2) + 2*M3(2) + M4(2))/6
         X(3) = X(3) + (M1(3) + 2*M2(3) + 2*M3(3) + M4(3))/6
C
         IX = (X(1) - XL)*CPUX
         IY = (X(3) - YL)*CPUY
C
         IF (IX .LT. 0 .OR. IX .GT. MCPAX     .OR.
     *       IY .LT. 0 .OR. IY .GT. MCPAY )   GOTO 1000
C
         COL(IX,IY) = I
C
1000   CONTINUE
C
C***********************************************************************
C***********************************************************************
C
      RETURN
      END