What'sBest! 6.0

Improved Integer Solver and Superior Ease-of-Use

The recently released What'sBest! 6.0 includes a number of significant enhancements and new features. Several of the enhancements focus on increasing the performance of the integer solver. This release also includes a number of modifications to improve ease of use and allow the user more control over the solution process.

New Enhanced Integer Solver

The What'sBest! integer solver has been completely revised and updated with state-of-the-art features. The solver's new heuristic procedure often allows the solver to find good integer solutions in a fraction of the time of earlier versions. The new integer solver has been able to find solutions to some problems that were previously unsolvable in a reasonable amount of time.

Increased Technical Control and Flexibility

What'sBest! 6.0 provides the user with extraordinary control of the preprocessing and solution process on integer models. A number of new integer tolerances allow the user to tailor the solution strategy to their particular problem structure. Experimenting with nondefault values for these tolerances can significantly improve runtimes on some integer models. The new list of tolerances include:

• Strong branching
• Warm start LP solver
• Cold start LP solver
• Time before switching on relative optimality tolerance
• Maximum cut application passes
• Relative cuts limit
• Absolute integrality tolerance
• Absolute optimality tolerance
• Different node selection strategies
• Enable/Disable ten different classes of constraint cuts
• Heuristic Level

Linearization of Products of Binary and Continuous Variables

In addition to the ability to linearize common Excel functions such as IF, MAX, MIN, and ABS, What'sBest! 6.0 has expanded its capabilities to automatically linearize products of binary variables and continuous variables. We have seen many models that use such products to model fixed cost scenarios. In earlier versions of What'sBest!, these variable product functions would have been classified as nonlinear and What'sBest! would have resorted to using the slower nonlinear solver. When the linearization option is enabled, What'sBest! automatically adds variables and constraints to convert these products to an equivalent, linear format.

Support for SUMIF() Function

What'sBest! now supports the SUMIF() function. This function can be very useful in simplifying models with certain structure. When you install What'sBest!, a network flow optimization sample model illustrating the use of the SUMIF function is included.

AutoUpdate Capability

What'sBest! will now automatically inform you if a new maintenance release becomes available. If so, you will have the option of downloading the updated software via your Web connection.

Expanded Documentation

To help you get up and running quickly and easily, the What'sBest! documentation now covers even more aspects of using the What'sBest! package. A sample model illustrating the new linearization option is included as well as many other sample models, which can be entirely linearized by the Linearization option.

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