ampl: option solver ilogcp; # change the solver ampl: option ilogcp_options 'option1=value1 option2=value2'; # specify options ampl: solve; # solve the problem
Solver options obtained with
$ ilogcp -=.
IBM ILOG CPLEX CP Optimizer Options for AMPL -------------------------------------------- To set these options, assign a string specifying their values to the AMPL option "ilogcp_options". For example: ampl: option ilogcp_options 'optimalitytolerance=1e-6 searchtype=restart'; Options: alldiffinferencelevel Inference level for "alldiff" constraints. Possible values: default low basic medium extended The default value is "default", which allows the inference strength of all "alldiff" constraints to be controlled via "defaultinferencelevel". branchlimit Limit on the number of branches made before terminating a search. Default = no limit. choicepointlimit Limit on the number of choice points created before terminating a search. Default = no limit. cppresolve 0 or 1 (default 1): Whether to activate presolve on the CP optimizer. debugexpr 0 or 1 (default 0): Whether to print debugging information for expression trees. defaultinferencelevel Inference level for constraints that have inference level set to "default". Possible values: low basic medium extended The default value is "basic". distributeinferencelevel Inference level for aggregated "numberof" ("IloDistribute") constraints. Possible values: default low basic medium extended The default value is "default", which allows the inference strength of all aggregated "numberof" constraints to be controlled via "defaultinferencelevel". dumpfile Specifies the name of a file where to dump the model before solving it. This file name must have extension ".cpo". Default = "" (don't dump the model). dynamicprobing Use probing during search. Possible values: auto off on The default value is "auto". dynamicprobingstrength Effort dedicated to dynamic probing as a factor of the total search effort. Default = 0.03. elementinferencelevel Inference level for "element" ("IloElement") constraints. Possible values: default low basic medium extended The default value is "default", which allows the inference strength of all "element" constraints to be controlled via "defaultinferencelevel". exportfile Specifies the name of a file where to export the model before solving it. This file name must have extension ".cpo". Default = "" (don't export the model). faillimit Limit on the number of failures allowed before terminating a search. Default = no limit. failuredirectedsearchemphasis Specifies the number of workers that use failure-directed search once it has started. The value does not have to be integer. For example, value 1.5 means that first worker spends 100% of the time by failure-directed search, second worker 50% and remaining workers 0%. Default = auto (depends on actual performance of the failure-directed search). logperiod Specifies how often the information in the search log is displayed. logverbosity Verbosity of the search log. Possible values: quiet terse normal verbose The default value is "quiet". mipdisplay Frequency of displaying branch-and-bound information (for optimizing integer variables): 0 (default) - never 1 - each integer feasible solution 2 - every "mipinterval" nodes 3 - every "mipinterval" nodes plus information on LP relaxations (as controlled by "display") 4 - same as 2, plus LP relaxation info. 5 - same as 2, plus LP subproblem info. mipinterval Frequency of node logging for mipdisplay 2 or 3. Default = 0. multipointnumberofsearchpoints Number of solutions for the multi-point search algorithm. Default = 30. obj:multi (multiobj) 0*/1: Whether to use multi-objective optimization. If set to 1 multi-objective optimization is performed using lexicographic method with the first objective treated as the most important, then the second objective and so on. obj:no (objno) Objective to optimize: 0 - None 1 - First (default, if available) 2 - Second (if available), etc. optimalitytolerance Absolute tolerance on the objective value. Default = 0. optimizer Specifies which optimizer to use. Possible values: auto - CP Optimizer if the problem has nonlinear objective/constraints or logical constraints, CPLEX otherwise cp - CP Optimizer cplex - CPLEX Optimizer The default value is "auto". outlev Synonym for "logverbosity". randomseed Seed for the random number generator. Default = 0. relativeoptimalitytolerance Relative tolerance on the objective value. Default = 1e-4. restartfaillimit Number of failures allowed before restarting search. Default = 100. restartgrowthfactor Increase of the number of allowed failures before restarting search. Default = 1.05. searchtype Type of search used for solving a problem. Possible values: auto depthfirst restart multipoint iterativediving The default value is "auto". sol:count (countsolutions) 0*/1: Whether to count the number of solutions and return it in the ".nsol" problem suffix. sol:stub (solstub, solutionstub) Stub for solution files. If "solutionstub" is specified, found solutions are written to files ("solutionstub & '1' & '.sol'") ... ("solutionstub & Current.nsol & '.sol'"), where "Current.nsol" holds the number of returned solutions. That is, file names are obtained by appending 1, 2, ... "Current.nsol" to "solutionstub". solutionlimit Limit on the number of feasible solutions found before terminating a search. Leaving the solution limit unspecified will make the optimizer search for an optimal solution if there is an objective function or for a feasible solution otherwise. tech:debug (debug) 0*/1: whether to assist testing & debugging, e.g., by outputting auxiliary information. tech:optionfile (optionfile, option:file) Name of solver option file. (surrounded by 'single' or "double" quotes if the name contains blanks). Lines that start with # are ignored. Otherwise, each nonempty line should contain "name=value". tech:timing (timing) 0*/1: Whether to display timings for the run. tech:version (version) Single-word phrase: report version details before solving the problem. tech:wantsol (wantsol) In a stand-alone invocation (no "-AMPL" on the command line), what solution information to write. Sum of 1 - Write ".sol" file 2 - Primal variables to stdout 4 - Dual variables to stdout 8 - Suppress solution message. temporalrelaxation 0 or 1 (default 1): Whether to use temporal relaxation. timelimit Limit on the CPU time spent solving before terminating a search. Default = no limit. timemode Specifies how the time is measured in CP Optimizer. Possible values: cputime elapsedtime The default value is "cputime". usenumberof 0 or 1 (default 1): Whether to aggregate "numberof" expressions by use of "IloDistribute" constraints. warninglevel Specifies the highest warning level to be displayed, all warnings higher than this level are masked. CP Optimizer warning levels run from 1 to 4, so setting this option to 0 turns off all warnings. Warnings issued may indicate potential errors or inefficiencies in your model. Default = 2. workers Number of workers to run in parallel to solve a problem. In addition to numeric values this option accepts the value "auto" since CP Optimizer version 12.3. Default = "auto".