private static SolverResult Solve(Config config, SolverConfig solverConfig, Instance instance)
{
var solver = new SolverFactory().Create(config.SolverName);
Console.WriteLine($"Starting solver: {solver.GetType().Name}");
var solverResult = solver.Solve(solverConfig, instance);
Console.WriteLine($"Solver finished.");
if (solverResult.Status == Status.Heuristic || solverResult.Status == Status.Optimal)
{
Console.WriteLine($"Solution found, checking its feasibility.");
var feasibilityChecker = new FeasibilityChecker();
var feasibilityCheckStatus = feasibilityChecker.Check(
instance,
solverResult.StartTimes,
solverConfig,
solverResult.Objective);
if (feasibilityCheckStatus != FeasibilityChecker.FeasibilityStatus.Feasible)
{
throw new Exception($"Solution not feasible: {feasibilityCheckStatus}");
}
Console.WriteLine($"Solution feasible.");
}
else
{
Console.WriteLine($"No solution found.");
}
return(solverResult);
}
private static int Run(CmdOptions opts)
{
var prescriptionPath = ExperimentPrescriptionPath(opts);
if (!File.Exists(prescriptionPath))
{
Console.WriteLine($"Experiment prescription file {prescriptionPath} does not exist.");
return(1);
}
var prescription = JsonConvert.DeserializeObject <Prescription>(
File.ReadAllText(prescriptionPath),
new JsonSerializerSettings()
{
DefaultValueHandling = DefaultValueHandling.Populate
});
if (!Directory.Exists(Program.DatasetsPath(opts)))
{
Console.WriteLine($"Datasets directory {Program.DatasetsPath(opts)} does not exist.");
return(1);
}
foreach (var datasetName in prescription.DatasetNames)
{
var datasetPath = DatasetPath(opts, datasetName);
if (!Directory.Exists(datasetPath))
{
Console.WriteLine($"Dataset directory {datasetPath} does not exist.");
return(1);
}
}
if (opts.FromScratch)
{
foreach (var datasetName in prescription.DatasetNames)
{
foreach (var solverPrescription in prescription.Solvers)
{
var solverResultsPath = ResultsExperimentDatasetSolverPath(
opts,
datasetName,
solverPrescription.Id);
if (Directory.Exists(solverResultsPath))
{
Directory.Delete(solverResultsPath, true);
}
}
}
}
// TODO:
if (opts.NumThreads != 1)
{
Console.WriteLine($"Parallel instance solving is not currently supported due to:");
Console.WriteLine($"- optimal switching cost is computed in parallel and there is no option to disable this");
return(1);
}
var objectLock = new object();
foreach (var datasetName in prescription.DatasetNames)
{
var instancePaths = Directory.EnumerateFiles(DatasetPath(opts, datasetName)).ToList();
foreach (var solverPrescription in prescription.Solvers)
{
var prescriptionSolverConfig = PrescriptionSolverConfig.Merge(
prescription.GlobalConfig,
solverPrescription.Config);
Parallel.ForEach(
instancePaths,
new ParallelOptions {
MaxDegreeOfParallelism = opts.NumThreads
},
(instancePath) => {
try
{
Console.WriteLine($"Solving {instancePath} using {solverPrescription.Id}");
var resultPath = ResultPath(
opts, datasetName, solverPrescription.Id, Path.GetFileName(instancePath));
if (opts.FromScratch == false && File.Exists(resultPath))
{
Console.WriteLine($"{instancePath} using {solverPrescription.Id} already solved");
return;
}
var instance = new InputReader().ReadFromPath(instancePath);
SolverConfig solverConfig;
lock (objectLock)
{
solverConfig =
prescriptionSolverConfig.ToSolverConfig(solverPrescription.SpecializedSolverConfig);
}
if (solverPrescription.InitStartTimesFrom != null)
{
var initStartTimesResultPath = ResultPath(
opts,
datasetName,
solverPrescription.InitStartTimesFrom,
Path.GetFileName(instancePath));
var initStartTimesResult = JsonConvert.DeserializeObject <Result>(
File.ReadAllText(initStartTimesResultPath));
if (initStartTimesResult.Status == Status.Optimal ||
initStartTimesResult.Status == Status.Heuristic)
{
solverConfig.InitStartTimes = initStartTimesResult.StartTimes;
}
}
if (solverPrescription.SubstractExtendedInstanceGenerationFromTimeLimit &&
solverConfig.TimeLimit.HasValue &&
instance.TimeForExtendedInstance.HasValue)
{
solverConfig.TimeLimit = new TimeSpan(Math.Max(
0,
solverConfig.TimeLimit.Value.Ticks - instance.TimeForExtendedInstance.Value.Ticks));
}
var solver = new SolverFactory().Create(solverPrescription.SolverName);
var solverResult = solver.Solve(solverConfig, instance);
if (solverResult.Status == Status.Optimal || solverResult.Status == Status.Heuristic)
{
var feasibilityChecker = new FeasibilityChecker();
var feasibilityStatus = feasibilityChecker.Check(instance, solverResult.StartTimes, solverConfig, solverResult.Objective);
if (feasibilityStatus != FeasibilityChecker.FeasibilityStatus.Feasible)
{
throw new Exception($"Feasibility check failed: {feasibilityStatus}, {instancePath}, {solverPrescription.Id}");
}
}
lock (objectLock)
{
if (!Directory.Exists(Path.GetDirectoryName(resultPath)))
{
Directory.CreateDirectory(Path.GetDirectoryName(resultPath));
}
}
File.WriteAllText(
resultPath,
JsonConvert.SerializeObject(Result.FromSolverResult(solverResult)));
}
catch (Exception)
{
Console.WriteLine($"Error while solving {instancePath} using {solverPrescription.Id}");
throw;
}
});
}
}
return(0);
}
