/**
  * Invokes the specified operator with the arguments.
  * <p/>
  * This method cannot be used for Confirming error return codes.  Any non-numeric Evaluation
  * result causes the current junit Test to fail.
  */
 public static double Invoke(Function f, ValueEval[] args, int srcCellRow, int srcCellCol)
 {
     try
     {
         return invokeInternal(f, args, srcCellRow, srcCellCol);
     }
     catch (NumericEvalEx e)
     {
         throw new AssertionException("Evaluation of function (" + f.GetType().Name
                 + ") failed: " + e.Message);
     }
 }