Changing a CP parameter value

Explains how to change a constraint programming option in the IDE.

Changing CP Optimizer parameters is useful to experiment with different values. The convenient way is to create a settings file in the IBM ILOG CPLEX Optimization Studio IDE and a different run configuration for each value, or set of values, you want to test. However, if you decide eventually that a particular setting is always needed for the model concerned, you can even set the parameter within the model by writing an execute IBM ILOG Script block. For an example, see Changing CP parameters in the Language User’s Manual.

For example, you can change the verbosity of the log displayed in the Engine Log tab of the Output window.

To set a CP parameter in the IDE:

  1. Create a settings file for the steelmill project by choosing File > New > Settings from the main menu.

    In the popup window, type steelmill.ops as the name of the settings file and click Finish.

  2. Drag and drop the steelmill.ops settings file into the Basic Configuration run configuration.

    See also Adding a settings file in Getting Started with the IDE.

  3. In the settings file displayed in the IDE editor, click Constraint Programming > Search control > Log control.
  4. Select Quiet from the Log verbosity drop-down list (see Figure 1).
    Figure 1. Setting the Engine Log verbosity
    Setting Engine log verbosity
  5. Execute the Basic Configuration for the project.

The Engine Log tab is empty. This is the result of the Quiet setting.

You can now close the route and steelmill projects in the IBM ILOG CPLEX Optimization Studio IDE.