Formula

The context menu of the Plot Window as well as the Data Browser Config View allows the addition of formulas.

Formula Configuration

When adding a formula, or later selecting it in the Config View, the Formula Configuration Dialog opens.

Formula Config

  1. The Inputs section lists all the PVs in the current configuration as possible inputs, and allows the assignment of shorter Variable names for use in the formula. Click on a Variable name to edit.
  2. Edit the formula, either by typing directly in the Formula text field, or by using the Functions and Basic Calculations.
  3. The Parsed Formula info on the bottom will show basic error messages.

Basic Calculations

... follow the behavior of most pocket calculators.

Functions

Formula Behavior at Runtime

The formula is evaluated based on the data shown in the plot, because this allows seamless operation on archived as well as life samples from different sources.

Formula in Plot

On the downside, the data quality of computed samples is always considered "interpolated" and limited to the time stamp granularity of what's visible in the plot. When trying to export data from both the archive and a formula, a corresponding warning points this out.