Variability Modeling > Making decisions for a product model > Product models > Creating a product model from a previous version of a product line model
  
Creating a product model from a previous version of a product line model
You can create a Product Model from a previous version of a Product Line Model (a protected model) in the following ways:
• Using an existing decision set.
Modeler creates the Product Model from the protected Product Line Model using a Decision Set in that protected Product Line Model.
• Using a new decision set.
Modeler creates the Product Model from the protected Product Line Model using a Decision Set that is defined in a private sandbox of that Product Line Model.
• After making changes to the model.
Modeler creates the Product Model from a private sandbox of the protected Product Line Model using a Decision Set defined in that private sandbox. Note that you cannot change a protected Product Line Model, so the changes have to be made in a private sandbox of that protected Product Line Model.
To create a product model from a previous version of a product line model - using an existing decision set:
1. From Modeler or the Variant Selector, open the previous version of the Product Line Model from which you want to create a Product Model. See Opening a model in the variant selector.
2. Create the Product Model from the required Decision Set using the Create Product Model command or button. See Creating a product model.
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You can create a Product Model using a Decision Set only when there are no inconsistencies in that Decision Set and at least one Decision has been made. See:
Modeler creates the Product Model from the previous version of the Product Line Model.
To create a product model from a previous version of a product line model - using a new decision set:
1. Through the Model Explorer, create a private sandbox from the previous version of the Product Line Model from which you want to create a Product Model. See Creating a branch of a model (repository-based CM).
2. From Modeler, open the private sandbox you created.
3. Create a Decision Set, through which the Product Model will be created. See Creating a decision set.
4. Through the Decision Set Editor or the Variant Selector, choose the Variants to include and exclude for the Decision set. See Choosing variants to include and exclude through the decision set editor and Choosing variants to include and exclude through the variant selector.
5. Create the Product Model from the required Decision Set using the Create Product Model command or button. See Creating a product model.
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You can create a Product Model using a Decision Set only when there are no inconsistencies in that Decision Set and at least one Decision has been made. See:
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The private sandbox is used only to create and define Decision Sets.
To create a product model from a previous version of a product line model - after making changes to the model:
1. Through the Model Explorer, create a private sandbox from the previous version of the Product Line Model from which you want to create a Product Model. See Creating a branch of a model (repository-based CM).
2. From Modeler, open the private sandbox you created.
3. Make the required changes to the Product Line Model in the private sandbox.
4. Create a Decision Set, through which the Product Model will be created. See Creating a decision set.
5. Through the Decision Set Editor or the Variant Selector, choose the Variants to include and exclude for the Decision set. See Choosing variants to include and exclude through the decision set editor and Choosing variants to include and exclude through the variant selector.
6. Create the Product Model from the required Decision Set using the Create Product Model command or button. See Creating a product model.
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You can create a Product Model using a Decision Set only when there are no inconsistencies in that Decision Set and at least one Decision has been made for a Variant. See:
Modeler creates the Product Model from the private sandbox using the Decision Set in the private sandbox.