IsValid
About the function
A time series reference specified by @t(‘TheReference’) may give no result. The reason for this may be one of the following:
- TheReference does not exist.
- There is no connection to a physical time series from the current context and there is no calculation associated with this time series attribute.
In these cases the system displays a warning message in the Nimbus Object Structure log. The warning message informs it could not resolve TheReference for a given object.
You may use either IsValid or Valid to handle these cases.
Syntax
- IsValid(t)
- IsValid(s,s)
- IsValid(T)
Description
| Type | Description |
|---|---|
| t | Source time series that is normally the result of a @t('TheReference'). |
The function returns 1 or 0 representing true or false.
Description
| Type | Description |
|---|---|
| s | Expected type of target, i.e. the entity found from the search/navigation defined in the second argument. Valid target codes are 't', 'd', 's', 'T', 'D' or 'S'. The codes represents time series, numeric, string, time series array, numeric array and string array respectively. |
| s | TheReference - The search/navigation string which defines where to go to find the target entity. |
This variant checks if there is a target of specified type available from the calculation context. If the target of the expected type is found, then the function returns 1 (representing true), otherwise the function returns 0. The function does not produce any log events when lookup fails.
Description
| Type | Description |
|---|---|
| T | An array of time series that is normally the result of a @T('TheReference'). |
The function returns 1 or 0 representing true or false. It returns true if there are time series in the array and some of these are connected to physical time series or have associated calculation expression.
Examples
In this example the Watercourse objects named Lyse and Sauda have an ownership relation has_HydroPlant where the HydroPlant object
type have a time series attributes Income and Production. The Income attribute have an associated expression.
The HydroPlant objects below Lyse do not have any physical time series attached to the Production attribute, but those below Sauda have.
Case 1
- The expression on a Watercourse attribute is like this
- ## = @IsValid(@T('has_HydroPlant.Income'))
| Time | Sauda | Lyse |
|---|---|---|
| 2020-12-31T23:00:00Z | 1.00 | 1.00 |
The result shows that the calculation returns 1 (true) for both Lyse and Sauda.
Case 2
- The expression on a Watercourse attribute is like this
- ## = @IsValid(@T('has_HydroPlant.Production'))
| Time | Sauda | Lyse |
|---|---|---|
| 2020-12-31T23:00:00Z | 1.00 | 0.00 |
The result shows that the calculation returns 1 (true) for Sauda and 0 for Lyse because there is no series connected to Production.