/// <summary>
/// Creates, populates and exports a plot that shows the
/// * produced amounts
/// * satisfied demands by source (current production or from inventory)
/// * remaining inventory at the end of a period.
/// </summary>
/// <param name="solvedClspModel">It is assumed that <see cref="CapacitatedLotsizingModel.Model"/> is solved and the Solution values are written to the Variables.</param>
public static void CreateAndExportLotSizingPlot(CapacitatedLotsizingModel solvedClspModel)
{
var plotModel = CreatePlottingCanvas();
AddProducedAmountToPlot(solvedClspModel, plotModel);
AddDemandSatisfactionToPlot(solvedClspModel, plotModel);
AddRemainStorageToPlot(solvedClspModel, plotModel);
ExportPlot(plotModel);
}
private static void AddProducedAmountToPlot(CapacitatedLotsizingModel clspModel, PlotModel oxyPlot)
{
var currentProduction = clspModel.PeriodInformation.Select(pi => new ColumnItem(clspModel.x[pi].Value)).ToList();
var productionSeries = new ColumnSeries()
{
Title = "Current Production",
FillColor = OxyColor.FromRgb(byte.Parse("165"), byte.Parse("185"), byte.Parse("79"))
};
productionSeries.Items.AddRange(currentProduction);
oxyPlot.Series.Add(productionSeries);
}
private static void AddRemainStorageToPlot(CapacitatedLotsizingModel clspModel, PlotModel oxyPlot)
{
var dataPoints = clspModel.PeriodInformation.Select(pi => new ColumnItem(clspModel.s[pi].Value)).ToList();
var series = new ColumnSeries()
{
Title = "Remaining Inventory",
FillColor = OxyColor.FromRgb(byte.Parse("82"), byte.Parse("35"), byte.Parse("152"))
};
series.Items.AddRange(dataPoints);
oxyPlot.Series.Add(series);
}
/// <summary>
/// The main method
/// </summary>
/// <param name="args">
/// no arguments required
/// </param>
static void Main(string[] args)
{
// create time steps with their "name", demand, setup cost,
// production cost per unit, inventory cost per unit
var csv = new CsvReader(File.OpenText("timesteps.csv"));
csv.Configuration.Delimiter = ";";
csv.Configuration.CultureInfo = new CultureInfo("en-US");
var periodInformation = csv.GetRecords <PeriodInformation>();
// use default settings
var config = new Configuration
{
NameHandling = NameHandlingStyle.Manual,
ComputeRemovedVariables = true
};
using (var scope = new ModelScope(config))
{
// create a model, based on given data and the model scope
var clspModel = new CapacitatedLotsizingModel(periodInformation);
var solverCfg = new GurobiSolverConfiguration()
{
ModelOutputFile = new FileInfo("clsp.lp"),
};
// Get a solver instance, change your solver
var solver = new GurobiSolver(solverCfg);
// solve the model
var solution = solver.Solve(clspModel.Model);
// print objective and variable decisions
Console.WriteLine($"{solution.ObjectiveValues.Single()}");
clspModel.y.Variables.ForEach(x => Console.WriteLine($"{x.ToString().PadRight(36)}: {x.Value}"));
clspModel.x.Variables.ForEach(y => Console.WriteLine($"{y.ToString().PadRight(36)}: {y.Value}"));
clspModel.s.Variables.ForEach(s => Console.WriteLine($"{s.ToString().PadRight(36)}: {s.Value}"));
clspModel.Model.VariableStatistics.WriteCSV(AppDomain.CurrentDomain.BaseDirectory);
PlottingUtils.CreateAndExportLotSizingPlot(clspModel);
}
Console.ReadLine();
}
private static void AddDemandSatisfactionToPlot(CapacitatedLotsizingModel clspModel, PlotModel oxyPlot)
{
var usedStorage = new List <ColumnItem>();
var usedProduction = new List <ColumnItem>();
foreach (var currentPeriod in clspModel.PeriodInformation)
{
var endStorage = clspModel.s[currentPeriod].Value;
var producedAmount = clspModel.x[currentPeriod].Value;
// basically represents the flow conservation constraint
var initialStorage = -producedAmount + endStorage + currentPeriod.Demand;
// split bar item in 2 sections.
var demandFromStorage = Math.Min(initialStorage, currentPeriod.Demand);
var demandFromProduction = Math.Min(currentPeriod.Demand - demandFromStorage, producedAmount);
usedStorage.Add(new ColumnItem(demandFromStorage));
usedProduction.Add(new ColumnItem(demandFromProduction));
}
var storageSeries = new ColumnSeries()
{
Title = "Demand from Inventory",
IsStacked = true,
StackGroup = "DemandSatisfaction",
FillColor = OxyColor.FromRgb(byte.Parse("132"), byte.Parse("122"), byte.Parse("178"))
};
storageSeries.Items.AddRange(usedStorage);
var productionSeries = new ColumnSeries()
{
Title = "Demand from Production",
IsStacked = true,
StackGroup = "DemandSatisfaction",
FillColor = OxyColor.FromRgb(byte.Parse("245"), byte.Parse("174"), byte.Parse("78"))
};
productionSeries.Items.AddRange(usedProduction);
oxyPlot.Series.Add(storageSeries);
oxyPlot.Series.Add(productionSeries);
}