19 articles
Measures & Calculations
The Measure HierarchyEvery Infohub model is a pyramid — a few measures that read data, and many more that summarise it.Retrieved MeasuresThe measures that actually read your plant — how retrieval works, and why most of them should be at the Tag interval.Aggregated MeasuresHow aggregation chains are built, why they must be contiguous, and what happens when the period underneath is incomplete.Choosing the Right Aggregation TypeSum, Average, Counter, or Last — the decision that causes more rework than any other in Infohub.Measure Reference: Intervals, Retrieval, and Aggregation TypesThe complete set of aggregation types, interval types, and retrieval types.Manual Entry MeasuresCapturing the numbers no system holds — targets, lab results, downtime reasons — and why they need protecting.Projected Measures and Entry DefaultsFuture periods on a measure, Set to Previous Value and its siblings, and how projections and defaults interact with backfill.Calculated MeasuresWhen to compute rather than aggregate, how dependencies drive recalculation, and the mistakes that cause stuck values.Tag TransformsReshaping a tag's stream before anything aggregates it — shifting it in time, taking a window around each point, or latching it to a trigger.Calculation Expression ReferenceInfohub calculations are compiled C#. This is everything an expression has in scope.Tag-Level CalculationsCustom-expression tags in depth — the per-point execution model, windowed filtering, TagProxy in functions, and why null handling decides everything.Built-in Function ReferenceAll 41 built-in calculation functions across 7 libraries, with the exact call syntax an expression needs.Enumeration ReferenceEvery fixed choice list in Infohub — 67 of them — with the options each one offers.The Zero GuardEvery division in an Infohub calculation needs protecting, and the pattern is always the same.Custom FunctionsReusable C# your calculations can call — what to put in a function library, and the caching behaviour to know about.Interval Types and Time SchemesInfohub does not assume a day starts at midnight. A time scheme is where you tell it when your periods begin.Shifts, Financial Years, and Custom PeriodsShift schemes, rotating patterns, financial calendars, and what to do when your periods do not follow a rule.Format StringsInfohub format strings are .NET format strings — including the three-section trick that turns a number into Pass or Fail.Units of MeasureInfohub stores the unit as free text and converts nothing — so consistency is entirely a matter of discipline.