Defining Module Inputs and Module Outputs

To allow model variable values to be used as values in a module, you have to define module variables as either module inputs or module outputs.

• A module input is a variable in the module (a stock, a flow, or a converter) that contains information that the module needs in order to run. Although you can explicitly define a variable as a module input, you aren't required to; when you assign a variable as a module input (by using the Assign Input To command), that variable is automatically made a module input.
• A module output is a variable in the module that contains information generated by the module and that can supply a value to other connected variables or modules. Variables directly connected into a module (via a connector from the variable to the module) can be assigned to a module input in the connected module without explicitly defining them as outputs. These variables are providing data into the connected module. On the other hand, variables that are providing data out of the module (into the model that contains the module, or into another module) must be explicitly defined as outputs.

Note: You can also define a variable to be neither a module input nor a module output by selecting the Neither option.

To Define a Variable as a Module Input or Module Output

1. Navigate into the module you want to define a variable as a module input or output for.
2. Right-click the variable that you want to define, choose Module, and then choose Accept Input, Provide Output, or Neither.

Note: Changing a variable’s input/output definition disconnects any existing assignments made between that variable and another variable.

See Also