You must use the FCOPEN function in combination with other OLAP DML statements as outlined in "Forecasting Programs".
The name of the forecasting context.
An INTEGER expression that is the handle to a different forecasting context that was previously-created using the FCOPEN function. Oracle OLAP initializes the new forecasting context with the same options as the forecasting context specified by this parameter. (See the FCSET command for descriptions of the options that specify the characteristics of a forecasting context.)
For an example of a forecasting program, see Example 9-118, "A Forecasting Program".