Calls to user-defined or third-party functions are allowed. The functions may be written in Visual Basic or they may be in XLL or COM Automation DLL libraries that have been opened in Microsoft Excel. To be compatible with Extreme Speed, user-defined functions must be “pure”. A pure function is one that computes its value solely on the basis of values passed to it as arguments. Range arguments in user-defined functions are only compatible with Extreme Speed when they are handled as Variant types. User-defined functions whose arguments are static (their values do not change during a simulation) are not called by Extreme Speed unless the Volatile property of the function has been set.
User-defined macros cannot be run during a simulation in Extreme speed, only before or after.
For details on these issues and more information about using user-defined functions and macros with Extreme speed, see the Oracle Crystal Ball Reference and Examples Guide.