Universal calculation engine

The universal calculation engine (UCE) performs logical and mathematical operations on data from interval streams. It returns either a vector representing a new stream of interval data, or a scalar, depending on the calculation.  The UCE is also the means through which all internal IEE and external applications request interval stream data through an XML API.

UCE uses a formula to perform calculations on readings data from one or more channels. The formula results that are calculated by the UCE are used in multiple areas throughout IEE, including:

  • Formula Channels. In aggregations, netting, losses, Time of Use (TOU), and billing determinants.

  • Validation, Estimation, and Editing. In user-defined validation rules, and algorithm-based estimation.

  • Graphs and Reports. In on-the-fly analysis and all background calculations.

  • Exports. In billing determinants and all background calculations.

Regardless of which area the formula is used, the mechanism for specifying the formula is the same.

All of the functions in the UCE begin with the @ symbol.

When the UCE performs an the operation by calculating based on a the formula to produce the requested data, the channel is called a formula channel (as opposed to a metered channel). A metered channel has real data associated with it. The channel retrieves actual data by accessing the database. A formula channel has no real data associated with it. The UCE uses a formula string to create the data for the channel. For example, formula channels can provide aggregated values across metered channels by using the formula: A:1 + B:1. This formula adds all of the interval values in channel A:1 to all of the interval values in B:1 and produces a new stream of data that is returned by the UCE.

The UCE interface for creating entering virtual channel formulas is the Formula Builder. The Formula Builder consists of two modes,Using the formula builder to configure a basic formula and Using the formula builder to configure an advanced formula. Your IEE logon credentials determine whether you have basic or advanced UCE capabilities. To change the level, see your system administrator.

The following features are available in both modes:

  • A syntax check occurs before the formula is saved.

  • The Basic tab checks whether the referenced channels exist Existence of all referenced channels are verified before the formula is saved.

  • When setting up a new service point, reference can be made to all channels at the same service point that have been established, but that have not yet been saved.  

  • Unit of Measure (UOM) type checks occur to verify that all UOMs used in the formula are the same or are the appropriate UOMs in unit conversion formulas.  If this check fails, you are notified and can decide to continue and save the formula, or cancel the operation.

The Formula Builder tool creates both basic and advanced UCE formulas to analyze and process interval and register data. You can access the Formula Builder from a number of IEE windows that incorporate formula calculations in their operations. The Formula Builder is a dialog that allows formulas to be constructed and configured, and then entered into the formula field on the access window.

You can choose between two methods of constructing formulas. The Formula Builder dialog has two tabs:

  • Basic applies one of four aggregation types to two or more Service Points. Aggregation options are ISUM, IAVG, IMAX, and IMIN.

  • Advanced allows formulas to be constructed on a "whiteboard," either by typing them in directly, or through the use of the Expression Builder tool. The scrollable white board supports cut-and-paste from within IEE or from external applications such as Microsoft Excel.

You must have a good working knowledge of Boolean logic and principles of interval data calculations to use Formula Builder.