AIMMS execution options


Many aspects of the way in which AIMMS behaves during a session can be customized through the AIMMS execution options. Such options can be set either globally through the options dialog box, or from within the model using the OPTION statement. As every project has its own requirements regarding AIMMS’ behavior, option settings are stored per project in the project file.

Option types

AIMMS offers options for several aspects of its behavior. Globally, the AIMMS execution options can be categorized as follows.

  • Project options: how does AIMMS behave during startup, and how does AIMMS appear during a project.

  • Execution options: how does the AIMMS execution engine with respect to numeric tolerances, reporting, case management and various other execution aspects.

  • General solver options: how does AIMMS behave during the matrix generation process, and which information is listed.

  • Specific solver options: how are the specific solvers configured that are used in the project.

Option dialog box

Through the Settings-Project Options menu you can open the global AIMMS Options dialog box illustrated in Fig. 65.

The AIMMS **Options** dialog box

Fig. 65 The AIMMS Options dialog box

In this dialog box, an option tree lists all available AIMMS execution and solver options in a hierarchical fashion.

Modifying options

After selecting an option category from the left-hand side of the Options dialog box, you can modify the values of the options in that category on the right-hand side of the dialog box. As illustrated in Fig. 65, AIMMS lists the currently selected value for every option (in the first edit field) along with the allowable range of all possible option values (in the second field). Option values can be either integer numbers, floating point numbers or strings, and, depending on the option, you can modify its value through

  • a simple edit field,

  • radio buttons,

  • a drop-down list, or

  • a wizard in the case where the value of an option is model-related.

Committing options

With the Apply button, you can commit the changes you have made to the value of a particular option and continue changing other options; the OK button will commit the changes and close the option dialog box. With the Default button at the right-hand side of the dialog box, you can always reset the option to its default value. It is only active when the option has a nondefault value.

Option description

When you have selected an option, and need to know more about its precise meaning before changing its value, you can press the Help button at the right-hand side of the options dialog box. As illustrated in Fig. 66,

Option help

Fig. 66 Option help

this will open a help window containing a more detailed description of the selected option.

Options with nondefault value

To help you quickly identify all the options which you have modified for a particular project, all modified options are summarized at the end of the options tree in a special section, Options with nondefault value. You can modify these options either in this section, or in their original locations. If you set a modified option back to its default value, it will be removed from the nondefault section. When you select an option from the Options with nondefault value section, the locate Location in Tree button will become available. Pressing this button will select the originating option category in the option tree.

Copying solver options

When you add a new version of some solver to the solver configuration (see Solver configuration for a description of how to add a new solver), the options of this new solver will appear in the Specific Solvers category. To copy solver options from the old solver version (e.g. Cplex 11.1 to CPLEX 12.6), select the source solver in the option tree and select the Copy Option command from the right-mouse popup menu. This will open the Copy Options dialog box as shown in Fig. 67.

The **Copy Options** dialog box

Fig. 67 The Copy Options dialog box

By default this dialog will only show options that differ between both solvers plus options that are only available in one of the two solvers. Once you press the Ok button, all options that remain in this list (and are available in both solvers) are copied from the source to the destination solver.

Searching for options

When you know (part of) the name of an option, but do not know where it is located in the option tree, you can use the search facility in the lower left- hand part of the option dialog box to help you find it. When you enter (part of) an option name, AIMMS will jump to the first option in the tree whose name contains the entered string.

Setting options within the model

In addition to modifying option values in the options dialog box, you can also set options from within your model using the OPTION statement. The OPTION statement is discussed in The OPTION and PROPERTY Statements. While changes to option values in the options dialog box are stored in the project file and reused at the beginning of the next project session, run time option settings are lost when you close the project. Setting options during run time can be convenient, however, if different parts of your model need different option settings.