public AreaEval Offset(int relFirstRowIx, int relLastRowIx,int relFirstColIx, int relLastColIx){if (_refEval == null){return _areaEval.Offset(relFirstRowIx, relLastRowIx, relFirstColIx, relLastColIx);}return _refEval.Offset(relFirstRowIx, relLastRowIx, relFirstColIx, relLastColIx);}