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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';


convergence_tolerance1e-6Stopping criterion
crash_iteration_limit50Maximum iterations allowed in crash
crash_methodpnewtonpnewton or none
crash_minimum_dimension1Minimum problem dimension required to perform crash
crash_nbchange_limit1Number of changes to the basis allowed
cumulative_iteration_limit10000Maximum minor iterations allowed
lemke_startautomaticFrequency of lemke starts (automatic, first, always)
major_iteration_limit500Maximum major iterations allowed
minor_iteration_limit1000Maximum minor iterations allowed in each major iteration
nmsyesAllow searching, watchdoging, and non-monotone descent
nms_initial_reference_factor20Controls size of initial reference value
nms_memory_size10Number of reference values kept
nms_mstep_frequency10Frequency at which m steps are performed
nms_searchtypepathpath or line
outputyesTurn output on or off. If output is turned off, selected parts can be turned back on.
output_crash_iterationsyesOutput information on crash iterations
output_crash_iterations_frequency1Frequency at which crash iteration log is printed
output_errorsyesOutput error messages
output_linear_modelnoOutput linear model each major iteration
output_major_iterationsyesOutput information on major iterations
output_major_iterations_frequency1Frequency at which major iteration log is printed
output_minor_iterationsyesOutput information on minor iterations
output_minor_iterations_frequency500Frequency at which minor iteration log is printed
output_optionsnoOutput all options and their values
output_warningsnoOutput warning messages
proximal_perturbation0.0Initial perturbation
restart_limit3Maximum number of restarts (0 – 3)
time_limit3600Maximum number of seconds algorithm is allowed to run