/// <summary>
/// Executa o algoritmo do simplex habitual sobre os dados de entrada.
/// </summary>
/// <param name="data">Os dados de entrada.</param>
/// <returns>O resultado da execução.</returns>
/// <exception cref="ArgumentNullException">
/// Se os dados de entrada forem passados com um apontador nulo.
/// </exception>
public SimplexOutput <CoeffType> Run(SimplexInput <CoeffType, CoeffType> data)
{
if (data == null)
{
throw new ArgumentNullException("data");
}
else
{
var hasSolution = true;
var enteringVariable = this.GetNextEnteringVariable(data);
var state = enteringVariable != -1;
while (state)
{
var leavingVariable = this.GetNextLeavingVariable(
enteringVariable,
data.ConstraintsMatrix,
data.ConstraintsVector);
if (leavingVariable == -1)
{
hasSolution = false;
state = false;
}
else
{
this.ProcessReduction(
enteringVariable,
leavingVariable,
data.ConstraintsMatrix,
data.ConstraintsVector);
data.Cost = this.ProcessObjectiveFunction(
enteringVariable,
leavingVariable,
data.BasicVariables,
data.NonBasicVariables,
data.Cost,
data.ObjectiveFunction,
data.ConstraintsMatrix,
data.ConstraintsVector);
enteringVariable = this.GetNextEnteringVariable(data);
state = enteringVariable != -1;
}
}
if (hasSolution)
{
return(this.BuildSolution(
data.BasicVariables,
data.NonBasicVariables,
data.ConstraintsVector,
data.Cost));
}
else
{
return(new SimplexOutput <CoeffType>(null, default(CoeffType), false));
}
}
}
/// <summary>
/// Obtém a próxima variável de entrada.
/// </summary>
/// <param name="data">Os dados de entrada.</param>
/// <returns>A variável caso exista e -1 caso contrário.</returns>
private int GetNextEnteringVariable(SimplexInput <CoeffType, CoeffType> data)
{
var result = -1;
var value = this.coeffsField.AdditiveUnity;
var length = data.ObjectiveFunction.Length;
for (int i = 0; i < length; ++i)
{
var current = data.ObjectiveFunction[i];
if (this.coeffsComparer.Compare(current, this.coeffsField.AdditiveUnity) < 0)
{
if (this.coeffsComparer.Compare(current, value) < 0)
{
result = i;
value = current;
}
}
}
return(result);
}
/// <summary>
/// Obtém a próxima variável de entrada.
/// </summary>
/// <param name="data">Os dados de entrada.</param>
/// <returns>A variável caso exista e -1 caso contrário.</returns>
private int GetNextEnteringVariable(SimplexInput <CoeffType, SimplexMaximumNumberField <CoeffType> > data)
{
var result = -1;
var value = new SimplexMaximumNumberField <CoeffType>(
this.coeffsField.AdditiveUnity,
this.coeffsField.AdditiveUnity);
var length = data.ObjectiveFunction.Length;
for (int i = 0; i < length; ++i)
{
var current = data.ObjectiveFunction[i];
if (this.coeffsComparer.Compare(current.BigPart, this.coeffsField.AdditiveUnity) <= 0)
{
if (this.ComapareBigNumbers(current, value) < 0)
{
result = i;
value = current;
}
}
}
return(result);
}
