...
The Formula Editor allows you to associate a formula with a text field, date field, number field, and so on. Formulas allow you to define relationships between columns in your report. While formulas serve an important role, they can be difficult to create. The Formula Editor makes the process of creating a formula easy and efficient; it also validates the formula thereby minimizing errors. Follow the instructions below to create a formula:
...
Note: The formula syntax used in LibFormula is based on the OpenFormula standard. The full document is downloadable Download the complete documentation from Oasis: OASIS OpenFormula Specifcation