Changes to the User API in Version 2.8

There are some minor changes to the user interface in order to allow the use of the new features. If you have code written for an older version, you will have to make some very minor modifications before compiling with version 2.8.

• user_start_heurs() now includes as an optional return value a user-calculated estimate of the optimal upper bound. This estimate is used to control diving. See the description of the new diving rules for more information. Since this return value is optional, you need only add the extra argument to your function definition to upgrade to the 2.8 interface. No changes to your code are required.

• user_check_cut() now includes as an optional return value a user-defined assessment of the current quality of the cut. Since this return value is optional, you need only add the extra argument to your function definition to upgrade to the 2.8 interface. No changes to your code are required.

• user_select_candidates() now passes in the value of the current level in the tree in case the user wants to use this information to make branching decisions. Again, the new argument just needs to be added to the function definition. No changes to your code are required.