Program mkgrid
C
C   This program creates an 85x85 point grid in a 10x10 domain for the vortex
C   convection problem.  All outer boundaries have spacing halved for 
C   four cells to allow for use of the double fringe boundary condition.
C
      PARAMETER (N=85)
      REAL Z
      DIMENSION X(N)
C
C
C   Generate the 1D (x and y) distribution.
C
      DO I = 1,N
        IF (I .EQ. 1) THEN
          X(I) = 0.0
          GO TO 100
        ELSE IF (I .LE. 5 .OR. I .GT. N-4) THEN
          FAC = 1./(.2*(N-5))
        ELSE
          FAC = 1./(.1*(N-5))
        ENDIF 
          X(I)   = X(I-1) + FAC
100     CONTINUE
      ENDDO
C
C   Generate the z distribution.
C
      Z   = 1.
C
C   Write out the grid.
C
      OPEN(UNIT=1,FILE='grid.in',STATUS='UNKNOWN',FORM='FORMATTED')
      WRITE(1,*) N,N,1
      WRITE(1,*) (((X(J),J=1,N),K=1,N),L=1,1),
     &         (((X(K),J=1,N),K=1,N),L=1,1),
     &         (((Z,J=1,N),K=1,N),L=1,1)
      CLOSE(1)
C
C
      STOP
      END