PRODUCTS
PATH Directives for AMPL
To set these directives, assign a string specifying their values to the AMPL option path_options. For example:
ampl: option path_options 'restart_limit=1 logfile=log.tmp crash_method=none';
Options:
| Option | Default | Explanation |
|---|---|---|
| convergence_tolerance | 1e-6 | Stopping criterion |
| crash_iteration_limit | 50 | Maximum iterations allowed in crash |
| crash_method | pnewton | pnewton or none |
| crash_minimum_dimension | 1 | Minimum problem dimension required to perform crash |
| crash_nbchange_limit | 1 | Number of changes to the basis allowed |
| cumulative_iteration_limit | 10000 | Maximum minor iterations allowed |
| lemke_start | automatic | Frequency of lemke starts (automatic, first, always) |
| major_iteration_limit | 500 | Maximum major iterations allowed |
| minor_iteration_limit | 1000 | Maximum minor iterations allowed in each major iteration |
| nms | yes | Allow searching, watchdoging, and non-monotone descent |
| nms_initial_reference_factor | 20 | Controls size of initial reference value |
| nms_memory_size | 10 | Number of reference values kept |
| nms_mstep_frequency | 10 | Frequency at which m steps are performed |
| nms_searchtype | path | path or line |
| output | yes | Turn output on or off. If output is turned off, selected parts can be turned back on. |
| output_crash_iterations | yes | Output information on crash iterations |
| output_crash_iterations_frequency | 1 | Frequency at which crash iteration log is printed |
| output_errors | yes | Output error messages |
| output_linear_model | no | Output linear model each major iteration |
| output_major_iterations | yes | Output information on major iterations |
| output_major_iterations_frequency | 1 | Frequency at which major iteration log is printed |
| output_minor_iterations | yes | Output information on minor iterations |
| output_minor_iterations_frequency | 500 | Frequency at which minor iteration log is printed |
| output_options | no | Output all options and their values |
| output_warnings | no | Output warning messages |
| proximal_perturbation | 0.0 | Initial perturbation |
| restart_limit | 3 | Maximum number of restarts (0 – 3) |
| time_limit | 3600 | Maximum number of seconds algorithm is allowed to run |
