gcSpreadSheet1.Sheets[0].SetValue(0, 0, 1);
gcSpreadSheet1.Sheets[0].SetValue(0, 1, 2);
gcSpreadSheet1.Sheets[0].SetValue(0, 2, 3);
gcSpreadSheet1.Sheets[0].SetCustomName("customName1", 0, 0, new CalcDoubleExpression(12));
gcSpreadSheet1.Sheets[0].SetCustomName("customName2", 0, 0, "Average(20,45)");
gcSpreadSheet1.Sheets[0].SetCustomName("customName3", 0, 0, 1, 3);
gcSpreadSheet1.Sheets[0].SetFormula(1, 0, "customName1");
gcSpreadSheet1.Sheets[0].SetFormula(1, 1, "customName2");
gcSpreadSheet1.Sheets[0].SetFormula(1, 2, "sum(customName3)");