Logical expressions

The application allows formulas to be defined, in virtual meters, widgets or alerts. These are used to specify calculations that will be made dynamically from stored data from physical meters.

Conditions

IF(logical_expression, true_result, false_result)

Allows you to determine a result based on a condition. If logical_expression is true, then instruction1 is returned, otherwise instruction2 is returned.

For the condition, we can use the following operators:

• = to test for equality
• != to test for inequality
• >=, >, <=, < to test superiority, strict superiority, inferiority and strict inferiority respectively.
• AND can be used between 2 conditions to test whether they are true simultaneously (AND operator)
• OR can be used between 2 conditions to test if at least one of them is true (OR operator)

Constants can be used: true (true), false (false), and null (to force a missing value).

Exemples

IF(meter > 10, 1, 0)
Returns 1 if the counter is greater than 10, otherwise returns 0.

Replacing missing values

DEFAULT_ZERO(expression)

Replaces missing values (null) in the expression with 0.

Exemple

DEFAULT_ZERO(meter1)
Returns meter1 with the value zero in place of missing values (depending on meter time step).