Algorithm (BAlgorithm)

This component analyzes data by managing the execution of blocks in the Wire Sheet, which produces a result via the result block. You can view the result of processing an algorithm in various ways including, but not limited to: a control point with an Analytic Proxy Ext, a Bound Label widget with an Analytic Binding, a chart with an Analytic Binding or a table with an Analytic Binding. Algorithms are implemented with logic blocks linked together using a Wire Sheet. They may combine both historical and real-time data to produce results, which may be a trend or a single value.

Figure 61. Example of an Algorithm properties

To view an algorithm’s Property Sheet, open the Algorithm Manager (double-click Config > Services > AnalyticService > Algorithms), right-click the algorithm, and click Views > Property Sheet.

This view contains the properties described in the table below. Each added block contains additional properties.

In addition to the standard properties (Status, Fault Cause, and Facets), these properties are unique to this component.

Property	Value	Description
Enabled	`true` (default) or `false`	Determines if the algorithm processes all requests. `true` processes all requests. `false` prevents the algorithm from processing all requests.
Result	additional properties	Is a frozen property of the algorithm and must be the final block linked in the Wire Sheet to output the result of the algorithm being processed.
Facets	units, precision, min, max, etc.	Configure how to display historical and calculated values, such as units or precision. A unit is a standard facet that applies to both data input and data output. You use it for viewing a point’s value or algorithm’s result. If a units facet is assigned, it need not match the units facet of a Data Source or Data Definition; however, it must be correct for the raw value being processed and must be convertible to the corresponding unit specified in the Data Definition or Data Source.
Makes Trends	`true` (default) or `false`	Controls the processing of trend requests. `false` outputs a constant value for both value and trend requests. `true` outputs a trend with constant values for trend requests.
Aggregation	drop-down list( defaults to `First`)	Configures the default aggregation function passed through the algorithm when the Data Source block’s `Use Request Aggregation` property is set to `true` and the `Aggregation` property is not explicitly configured in the request. If aggregation is not enabled in the binding/settings window, the aggregation value defined in the Data Definition applies to all chart bindings, reports and tables. `And` returns the logical “and” of Boolean values. `Avg` returns the statistical mean, which is determined by calculating the sum of all values and dividing by the number of values. `Count` returns the total number or quantity of values in a combination. If you request this value on a binding in a PX view, the system counts the number of values based on the properties defined by the data source block and the algorithm’s Property Sheet. `First` returns the first value in the combination. `Last` returns the last value in the combination. `Max` returns the highest value in the combination. `Median` returns the value in the middle of a sorted combination—the number that separates the higher half from the lower half. `Min` returns the lowest value in the combination. `Mode` returns the statistically most frequently occurring number in the combination. `Or` returns the logical “or” of Boolean values. `Range` returns the statistical difference between the largest and smallest values in the combination. `Sum` adds together all values in the combination resulting in a single value. `Load Factor` returns the average value divided by peak value. `Std Dev` returns the standard deviation of the values in the combination.
Rollup	check box (if optional, and) drop-down list or ORD parameter (when configured in the data definition, defaults to `First`, when configured elsewhere, defaults to the value as defined in the Data Definition); rollup=option	Configures the default rollup function passed through the algorithm when the Data Source block `Use Request Rollup` property is set to `true` and the rollup property is not explicitly configured in the request. If rollup is not enabled in the binding/settings window, the rollup value configured in the Data Definition applies to all chart bindings, reports and tables. `And` returns the logical “and” of Boolean values. `Avg` returns the statistical mean, which is determined by calculating the sum of all values and dividing by the number of values. `Count` returns the total number or quantity of values in a combination. If you request this value on a binding in a PX view, the system counts the number of values based on the properties defined by the data source block and the algorithm’s Property Sheet. `First` returns the first value in the combination. `Last` returns the last value in the combination. `Max` returns the highest value in the combination. `Median` returns the value in the middle of a sorted combination—the number that separates the higher half from the lower half. `Min` returns the lowest value in the combination. `Mode` returns the statistically most frequently occurring number in the combination. `Or` returns the logical “or” of Boolean values. `Range` returns the statistical difference between the largest and smallest values in the combination. `Sum` adds together all values in the combination resulting in a single value. `Std Dev` calculates the standard deviation of the values in the combination. `Load Factor` calculates the average divided by peak (Max) value.
Min Interval	drop-down with time intervals (defaults to `None`)	Defines the minimum wait time between processing items in the queue. The default value of zero (0) does not enforce a minimum wait time. Triggered Poller components do not use a `Rate` property. You should use the `Min Interval` property to balance CPU load by slowing down the execution of items in the queue.
Max Interval	drop-down with time intervals (defaults to `None`)	Defines the maximum wait time between processing items in the queue. The default value of zero (0) does not enforce a maximum wait time.

What follows in the Property Sheet are containers for the various logic blocks. Logic block properties vary depending on the type of block. Each block is documented in the Logic blocks chapter.

Algorithm (BAlgorithm)

Figure 61. Example of an Algorithm properties

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