Grid sub.f90 - definition of the grid

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!Sample program for solving Smith-Hutton Test using different schemes 
!of covective terms approximation -  Grid's computing modul
!Copyright (C) 2005  Michail Kirichkov

!This program is free software; you can redistribute it and/or
!modify it under the terms of the GNU General Public License
!as published by the Free Software Foundation; either version 2
!of the License, or (at your option) any later version.

!This program is distributed in the hope that it will be useful,
!but WITHOUT ANY WARRANTY; without even the implied warranty of
!MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
!GNU General Public License for more details.

!You should have received a copy of the GNU General Public License
!along with this program; if not, write to the Free Software
!Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

!**********************************************************************
Subroutine Grid_rectangular

include 'icomm_1.f90'  
 
       x=0.
       y=0.

 SLx = 2.
 SLy = 1.

 Xbeg = -1.
 Ybeg =  0.

! SLx = 1.
! SLy = 1.

! Xbeg = 0.
! Ybeg = 0.

NXmax = 121
NYmax = 61

NXmaxP =  NXmax + 1
NYmaxP =  NYmax + 1
   
!-------------------------------------------------------------------------------------------

	DO 2 I=1, NXmax
	DO 2 J=1, NYmax
	
	X(I,J) = Xbeg + (SLx /(NXmax-1))* (i-1)
	 
  2     continue 	

 	DO 3 J=1, NYmax
	DO 3 I=1, NXmax
	
	Y(I,J) = Ybeg + (SLy /(NYmax-1))* (j-1) 

  3     continue 	

!-------------------------------------------------------------------------------------------

	open (22,file='GRID.dat') 
	
	WRITE(22,*)'VARIABLES = "X", "Y" ' 

      WRITE (22,*)' ZONE I=' ,NXmax, ', J=', NYmax, ', F=POINT'

	DO 1 J=1, NYmax
	DO 1 I=1, NXmax

	 WRITE (22,*) X(I,J), Y(I,J)  

  1     continue 	


	open (21,file='GRID.txt') 
	
	write(21,*) NYmax,NXmax

	DO 4 J=1, NYmax
	DO 4 I=1, NXmax

	 WRITE (21,*) X(I,J), Y(I,J)  

  4     continue 	

	close(21)
	 
Return
End