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Controls and Math Operations

Controls and Rules enable to perform some Actions on tag values, based on met Conditions. These tools allow you to build math driven automation tasks.

Controls

A Rackio Control is defined by a Rackio Condition and a Rackio Action.

from rackio.controls import Control

Rules

A Rackio Rule works the same way as a Rackio Control but it can handle multiple actions with a single condition.

from rackio.controls import Rule

So in order to define a Control or a Rule, we must define some conditions and actions ahead.

Conditions

You can set some conditions based on the tag values and between tag values, typical comparison expressions like >=, == or even use logical expressions like and and or.

Comparison Operators

from rackio.controls import Condition

# Conditions definitions

condition1 = Condition("T1",">=", "T2")
condition2 = Condition("T1","<", "T2")

Where T1 and T2, are tags already defined in Rackio. Evaluating these conditions will return True or False.

Logical Operators

from rackio.controls import OrCondition, AndCondition

# Conditions definitions

condition1 = Condition("T1",">=", "T2")
condition2 = Condition("T1","<", "T2")

condition3 = OrCondition([condition1, condition2])
condition4 = AndCondition([condition1, condition2])

Actions

Actions are the final step once a condition from a control or rule is met, you can choose between ValueAction or a MathAction. the first one takes a defined value and assigns to a defined tag, and the last one, can perform a mathematical expression on a tag value, this mathematical expression can contain other tags names and some math functions like exp or sin.

from rackio.controls import ValueAction, MathAction

action1 = ValueAction("T3", 40)
action2 = MathAction("T3", "T1 + T2")

Putting all together

Finally once you have defined conditions and actions, you can define your controls or rules.

from rackio.controls import Control, Rule

control1 = Control("C1", condition1, action1)
rule1 = Rule("R1", condition2, [action1, action2])

You have to define your controls and rules with a string name, so you can query then the control manager for any control or rule based on this defined name.

Control Manager

In order for Rackio to execute these controls and rules, they must be registered in the ControlManager.

from rackio import Rackio

app = Rackio()

app.append_control(control1)
app.append_rule(rule1)

Once you execute your app, the ControlWorker will handle all defined controls and rules in set time interval of 0.1 seconds.

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