Using Simulink

Data Typing Rules

Observing the following rules can help you to create models that are typesafe and, therefore, execute without error:

• Signal data types generally do not affect parameter data types, and vice versa.

• A significant exception to this rule is the Constant block, whose output data type is determined by the data type of its parameter.

• If the output of a block is a function of an input and a parameter, and the input and parameter differ in type, Simulink converts the parameter to the input type before computing the output.

• See Typecasting Parameters for more information.

• In general, a block outputs the data type that appears at its inputs.

• Significant exceptions include Constant blocks and Data Type Conversion blocks, whose output data types are determined by block parameters.

• Virtual blocks accept signals of any type on their inputs.

• Examples of virtual blocks include Mux and Demux blocks and unconditionally executed subsystems.

• The elements of a signal array connected to a port of a nonvirtual block must be of the same data type.
• The signals connected to the input data ports of a nonvirtual block cannot differ in type.
• Control ports (for example, Enable and Trigger ports) accept any data type.
• Solver blocks accept only double signals.
• Connecting a non-double signal to a block disables zero-crossing detection for that block.

Data Type Propagation

Enabling Strict Boolean Type Checking

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