ampl/mp v20131015

20131015

on GitHub

Gecode

• Multiple solution support: options countsolution and solutionstub, problem suffix nsol.

• Add the suffix icl to specify integer consistency level for constraints:

  subj to c1: alldiff ({i in 1..n} q[i]) suffix icl icl_dom;
  

  The suffix and possible values for it are defined in gecode.ampl.
  Requires AMPL version 20130906 or later.

• Add support for restart search and the following options to control the search:

  • restart: restart sequence type
  • restart_base: base for geometric restart sequence
  • restart_scale: scale factor for restart sequence

• New solve results to distinguish between the cases when a solver reaches different limits:

  400     time limit
  401     node limit
  402     fail limit
  403     solution limit
  

IlogCP

• The ilogcp solver is split into two: ilogcp for the IBM ILOG CP Optimizer and ilocplex for the CPLEX Optimizer.

• Multiple solution support: options countsolution and solutionstub, problem suffix nsol.

• The element constraint. Example:

   s.t. satisfyMaxLoad{t in Trips}:
     load[t] <= element({c in TruckConfigs} MaxTruckConfigLoad[c],
                        truckConfigs[t]);
  

• The in_relation constraint. Example:

   s.t. restrictConfigOfContainer{o in Orders}:
     in_relation(configOfContainer[o],
       {c in AllowedContainerConfigs[ProductTypes[o]]} c);
  

• Multiobjective optimization.

  minimize totalCost:
     sum{t in Trips}
       (if load[t] > 0 then
         element({c in TruckConfigs} TruckCost[c],
                 truckConfigs[t])) +
     sum{t in 0..NumTrips - 2} reconfigCost[t];
  minimize tripCount: count{t in 0..NumTrips - 1} (load[t] > 0);
  

• New solve result to distinguish between the cases when a user interrupts the solution process and a solver reaches a limit:

  400     limit
  

• Add the solutionlimit option.

JaCoP

• Multiple solution support: options countsolution and solutionstub, problem suffix nsol.

• New solve result to distinguish between the cases when a user interrupts the solution process and a solver reaches a limit:

  400     limit
  

• Add the solutionlimit option.

AMPLGSL

• Update GSL to version 1.16

See also New features of the AMPL CP interfaces for the presentation of some of the new features and truckfleet.ampl for the truck fleet model used in some of the examples above.