Through the calculation menu you are given a clear overview of the same wide variety of possible calculations you have access to in the classic spreadsheet.
In Sheetlet you can easily retrieve the specific calculation you need. Once found, just drag the calculation and drop it underneath the grid you wish to subject to calculation.
Calculations are presented as calculation grids. If your calculation does not depend on the above grid as a provider or should include more than one provider, just click the calculation grid to edit, slide and scroll to find the relevant provider and tab to add it. It will then be included in the calculation grid you have created.