Can we use a derived field to perform calculations?
You can use your derived field when you build a calculated field. Do you have an example of what you are trying to do and the fields you wish to use in your calculation?
LocalGrossAmount = PrintBillingInvoiceLinesRel.ExtentedAmount * 100
Extended Amount is a derived field here. Can we use this?
I would say to try this in Configuration Console
Select Configuration > Create. Click Compute in the Tailor Business Logic > Add A New Field column.
Enter your bus class.
Enter LocalGrossAmount in the field name.
Integer - extended type
calculation: PrintBillingInvoiceLinesRel.ExtentedAmount * 100