Stateflow User's Guide

Using Subcharts to Extend Charts

Subcharts are charts within charts. They provide a convenience for compacting your diagrams. This section shows you how to create and work with subcharts in the following topics:

• What Is a Subchart? -- Describes a subchart and its hierarchical position in a chart.
• Creating a Subchart -- Shows you how to create a subchart by converting a state, box, or graphical function into a subchart.
• Manipulating Subcharts as Objects -- Tells you how to move, copy, cut, paste, relabel, and resize subcharts.
• Opening a Subchart -- Tells you how to open a subchart to view and change its contents.
• Editing a Subchart -- Describes the way in which you edit the contents of subcharts.
• Navigating Subcharts -- Describes a set of buttons for navigating a chart's subchart hierarchy.

What Is a Subchart?

Stateflow allows you to create charts within charts. A chart that is embedded in another chart is called a subchart. The subchart can contain anything a top-level chart can, including other subcharts. In fact, you can nest subcharts to any level.

A subcharted state is a superstate of the states and charts that it contains. It appears as a block with its name in the block center. However, you can define actions and default transitions for subcharts just as you can for superstates. You can also create transitions to and from subcharts just as you can create transitions to and from superstates. Further, you can create transitions between states residing outside a subchart and any state within a subchart. The term supertransition refers to a transition that crosses subchart boundaries in this way. See Using Supertransitions to Extend Transitions for more information.

Subcharts enable you to reduce a complex chart to a set of simpler, hierarchically organized diagrams. This makes the chart easier to understand and maintain. Nor do you have to worry about changing the semantics of the chart in any way. Stateflow ignores subchart boundaries when simulating and generating code from Stateflow models.

Subcharts define a containment hierarchy within a top-level chart. A subchart or top-level chart is said to be the parent of the charts it contains at the first level and an ancestor of all the subcharts contained by its children and their descendants at lower levels.

Changing History Junction Properties

Creating a Subchart

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