text: public SharedFormulaGroup(SharedFormulaRecord sfr, CellReference firstCell){if (!sfr.IsInRange(firstCell.Row, firstCell.Col)){throw new ArgumentException("First formula cell " + firstCell.FormatAsString()+ " is not shared formula range " + sfr.Range.ToString() + ".");}_sfr = sfr;_firstCell = firstCell;int width = sfr.LastColumn - sfr.FirstColumn + 1;int height = sfr.LastRow - sfr.FirstRow + 1;_frAggs = new FormulaRecordAggregate[width * height];_numberOfFormulas = 0;}