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  C $Id: elcent.f,v 1.1 1991/02/21 15:43:04 gdsjaar Exp $
  C $Log: elcent.f,v $
  C Revision 1.1  1991/02/21 15:43:04  gdsjaar
  C Initial revision
  C
        SUBROUTINE ELCENT (ELCEN, IX, COORD, NDIM, NUMEL, NELNOD, NUMNP)
        DIMENSION ELCEN(NUMEL, *), IX(NELNOD, *), COORD(NUMNP, *)
  C
        IF (NDIM .EQ. 2) THEN
            DO 10 I=1, NUMEL
                ELCEN(I,1) = (COORD(IX(1,I),1) + COORD(IX(2,I),1) +
       *                      COORD(IX(3,I),1) + COORD(IX(4,I),1))/4.0
                ELCEN(I,2) = (COORD(IX(1,I),2) + COORD(IX(2,I),2) +
       *                      COORD(IX(3,I),2) + COORD(IX(4,I),2))/4.0
     10     CONTINUE
        ELSE
            DO 20 I=1, NUMEL
                ELCEN(I,1) = (COORD(IX(1,I),1) + COORD(IX(2,I),1) +
       *                      COORD(IX(3,I),1) + COORD(IX(4,I),1) +
       *                      COORD(IX(5,I),1) + COORD(IX(6,I),1) +
       *                      COORD(IX(7,I),1) + COORD(IX(8,I),1))/8.0
  C
                ELCEN(I,2) = (COORD(IX(1,I),2) + COORD(IX(2,I),2) +
       *                      COORD(IX(3,I),2) + COORD(IX(4,I),2) +
       *                      COORD(IX(5,I),2) + COORD(IX(6,I),2) +
       *                      COORD(IX(7,I),2) + COORD(IX(8,I),2))/8.0
  C
                ELCEN(I,3) = (COORD(IX(1,I),3) + COORD(IX(2,I),3) +
       *                      COORD(IX(3,I),3) + COORD(IX(4,I),3) +
       *                      COORD(IX(5,I),3) + COORD(IX(6,I),3) +
       *                      COORD(IX(7,I),3) + COORD(IX(8,I),3))/8.0
     20     CONTINUE
        END IF
        RETURN
        END
  