# Flow Control

## Overview

**Flow Control Nodes** are used to define the order in which logic is evaluated, allows a program to consider multiple conditions, and perform different actions based on those variable conditions.

**Nodes** in the **Flow Control** category fall into several subcategories.

## Relational Expression Nodes

*Relational expression* **Nodes** compare two values and yield a value based on the relationship of those inputs. These include the following:

* [**IsEqual**](https://docs.incari.com/incari-studio/2.0/toolbox/flow-control/is-equal) - Compares whether two values are *equal* in value, or *not equal*, depending on `Mode`. This is the equivalent of the `==` and `!=` operators in computer programming.
* [**IsGreaterEqual**](https://docs.incari.com/incari-studio/2.0/toolbox/flow-control/is-greater-equal) - Compares whether one value is *greater* than another, or if they are equal, depending on `Mode`. This is the equivalent of the `>` and `>=` operators in computer programming.
* [**IsLessEqual**](https://docs.incari.com/incari-studio/2.0/toolbox/flow-control/is-less-equal) - Compares whether one value is *less* than another, or if they are equal, depending on `Mode`. This is the equivalent of the `<` and `<=` operators in computer programming.

## Pulse Flow Nodes

**Pulse Flow Nodes** are mainly used to change the *control flow* of logic, which means executing different logic branches based on various *conditions*. To achieve truly dynamic programs, they are used in synergy with *relational expression* and *logical operator* **Nodes**.

* [**Branch**](https://docs.incari.com/incari-studio/2.0/toolbox/flow-control/branch) - Takes one of two paths based on its input **Boolean** value. Similar to an `if` statement in computer programming.
* [**Switch**](https://docs.incari.com/incari-studio/2.0/toolbox/flow-control/switch) - Takes one of several paths if the input value is equal to a path's corresponding, pre-defined value. If not, then the `Default` path is taken. Similar to a `switch` statement in computer programming.
* [**Toggle**](https://docs.incari.com/incari-studio/2.0/toolbox/flow-control/toggle) - Holds a **Boolean** *state*, which alternates between its opposite state every time the input **Pulse** is triggered.
* [**Select Data**](https://docs.incari.com/incari-studio/2.0/toolbox/flow-control/select-data) - Takes two or more pairs of **Pulse** and **Data** inputs and outputs the value corresponding to the input **Pulse** that the **Node** was executed by. This is a useful way to converge **Pulse Flow** into a single path.

Additionally, Incari has the [**Sequential Node**](https://docs.incari.com/incari-studio/2.0/toolbox/flow-control/sequential), which triggers all output **Pulses** sequentially and is used primarily as a means of grouping and organizing blocks of logic with a similar or combined purpose into a more visually readable way.

## See Also

* [**Boolean**](https://docs.incari.com/incari-studio/2.0/toolbox/math/boolean)

## External Links

* [*Control Flow*](https://www.computerhope.com/jargon/c/contflow.htm) on Computer Hope.
* [*Conditional Statement*](https://www.computerhope.com/jargon/c/contstat.htm) on Computer Hope.
* [*Logical Operation*](https://www.computerhope.com/jargon/l/logioper.htm) on Computer Hope.
* [*State*](https://www.techopedia.com/definition/696/state-computer-science) on Technopedia.