Unit Editor dialog box

Use the Unit Editor dialog box to create and delete Unit definitions for your model.

To open this dialog box, use one of the following methods:

Default Units

This displays a list of the Unit definitions that are built into Stella. These are commonly used units that are included for your convenience. The Unit Name appears first, followed by the Unit Equation, and Unit Aliases in parentheses. You can't change the default units, but you can extend them by adding new aliases as described in To Create New Units from Scratch.

My Units

This displays a list of the Unit definitions you've created. These are applied to every model you work with. To edit one of these, double-click to open the editing controls. To delete, click on the at the right.

Model Specific Units

This displays a list of the Unit definitions contained only in the model. You can create these specifically. They may also appear in models you get from other people; unit definitions in this category may have been in the My Units category of the model author. To edit one of these, double-click to open the editing controls. To delete, click on the at the right.

You can move a Unit definition from My Units to Model Specific Units by highlighting it and clicking on the >> button. You can move one back by clicking on the << button.

Note: If you remove a Unit definition from My Units, it won't be used in new models you create. If, however, it's used in a model other than the one currently opened, it will still be used, but will be kept in the Model Specific Units list. This is true for all models, including any concurrently opened in another Stella window.

For more information, see To Delete Units You've Created.

Unit Name

Type a unique name for the new unit of measure. The name can't be used by any other Unit definition in any category. The name must begin with a letter and contain only letters, numbers, and $. You can include spaces or underbars in the name interchangeably, with one or more of either being treated the same as a single space in comparing unit names (that is, a____b and a_b are considered the same when comparing units).

Unit Equation

Type the equation for the unit. If you leave the box blank, you must enter an alias. You can make a new unit equivalent to an existing unit by entering the existing unit name.

For more information about creating equations, see Creating Equations for Units.

Unit Alias

Enter a comma separated list of equivalent names for the Unit you're defining. This list can be empty if you've specified an equation, but one of an equation or an alias is required. If you simply want to use a name for a unit of measure, enter it directly in the Units entry for the model variable; you don't need to define it first.

Add to My Units Button

Click this button to add the new unit of measure to the "My Units" list. The entries you've made will be validated when you do this.

Add to Model Specific Units Button

Click this button to add the new unit of measure to the "Model Specific Units" list. The entries you've made will be validated when you do this.