Using TrendSpec to Produce Ad Hoc Trends
Geo SCADA Expert has a specification language that allows you to create ‘custom’ Ad Hoc Trends. This language is called TrendSpec and you can use it where ‘target’ displays for hyperlinks are defined:
- Mimic scripts
- Favorites List
- Hyperlink URLs.
TrendSpec works by allowing you to define the properties of an Ad Hoc Trend within the text of a hyperlink. There are many properties you can specify, including color settings, text settings and trace settings, which are stored within the hyperlink. When the hyperlink is selected, Geo SCADA Expert reads the TrendSpec definition in the hyperlink and applies the settings to the Ad Hoc Trend that is generated. This results in a ‘custom’ Ad Hoc Trend.
By using TrendSpec in conjunction with Geo SCADA Expert’s scripting features, you can create Ad Hoc Trends that:
- Use specified colors, text attributes, and so on
- Display multiple traces
- Allow users to choose which traces are shown.
- Can be the ‘targets’ of hyperlinks on Mimics
- Can be added to users’ Favorites Lists
To use TrendSpec, you create a TrendSpec definition, which contains the property settings that are to be used. You can create a TrendSpec definition as part of a script by using a suitable text editing application, or you can enter the definition directly into a Mimic’s Script Editor or the URL of a hyperlink. Many of the properties you can include in the definition are equivalent to the properties that you can specify on a Pre-Configured Trend.
When creating a TrendSpec Definition, you can write an entirely new definition to suit your requirements. Alternatively, you can Base a TrendSpec Definition on the Definition of Another Ad Hoc Trend.
In the following topics, we explain the syntax required for TrendSpec definitions and describe some of the ways you can use TrendSpec:
- The Basic TrendSpec Structure, including:
- The Mandatory Section Identifiers
- The Mandatory Values.
- The Optional Values that you can include in a TrendSpec definition.
- How to use TrendSpec to define:
- How to Base a TrendSpec Definition on the Definition of Another Ad Hoc Trend.
Also included is a section on Troubleshooting - TrendSpec.
For a series of examples that demonstrate how TrendSpec can be used to produce ‘custom’ ad hoc Trends, see Example Configuration.