REAL Q(10,20)
...
Q(3,5) = 1.0
CALL FIXQ(Q)
...

------------------------------

void fixq_( float a[20][10] )
{
   ...
   a[5][3] = a[5][3] + 1.;
   ...
}

extern void
     qref_( int[][10], int *);
...
 int m[20][10] = ... ;
 int sum;
...
 qref_( m, &sum );
...

------------------------------

SUBROUTINE QREF(A,TOTAL)
  INTEGER A(10,20), TOTAL
  DO I = 1,10
    DO J = 1,20
      TOTAL = TOTAL + A(I,J)
    END DO
  END DO
  ...