Use expressions in PI DataLink functions

Use expressions in PI DataLink functions to incorporate mathematical operations and calculations based on PI System data items. Functions that accept either a data item or an expression have Data item and Expression options at the top of the task pane.

1. Open the function task pane.

2. Select the Expression option at the top of the function task pane.

   The Data item(s) field becomes an Expression(s) field. The availability of other fields might change.

3. Enter the expression directly in the Expression(s) field, or enter a reference to a cell that contains a complete expression.

   You must use a cell reference in the following cases:

   • To enter multiple expressions for a function

     In the Expression(s) field, enter a range of cells that contain complete expressions.

   • To enter an expression that includes an Excel function or Excel calculation operator, such as the ampersand used to reference another cell

     Enter these expressions in a cell as an Excel formula.

     Tip: Expressions entered with cell references are easier to view and edit. Make future worksheet maintenance easier by using cell references to enter expressions.