Access this dialog box from the Expression Definition dialog box, or when creating a user-defined measure in the Measure Definition dialog box. When you select one of the following functions, it appears as part of your definition in expression area.

The default variable x for the functions is time, t. You can select another variable, such as a measure, from the x = list at the top of the dialog box. You can also enter a constant value or an expression in the text box. You can select a function by double-clicking or by single-clicking and closing the dialog box. The function appears in the expression area with the selected variable or entered expression.