private static double[,] createConstraintMatrix(int numberOfVariables,
LinearConstraint[] constraintArray, out double[] b, out int equalities)
{
// First of all, separate the equality constraints from the inequalities.
constraintArray.StableSort((c1, c2) => c1.ShouldBe.CompareTo(c2.ShouldBe));
int numberOfConstraints = constraintArray.Length;
double[,] A = new double[numberOfConstraints, numberOfVariables];
b = new double[numberOfConstraints];
equalities = 0;
for (int i = 0; i < constraintArray.Length; i++)
{
LinearConstraint constraint = constraintArray[i];
if (constraint.NumberOfVariables > numberOfVariables)
throw new ArgumentException("The number of variables in the constraint exceeds the number of variables for the problem.");
for (int j = 0; j < constraint.VariablesAtIndices.Length; j++)
{
int k = constraint.VariablesAtIndices[j];
if (k >= numberOfVariables)
throw new ArgumentException("The constraint refers to a variable index which is not present on the objective function.");
if (constraint.ShouldBe == ConstraintType.GreaterThanOrEqualTo ||
constraint.ShouldBe == ConstraintType.EqualTo)
{
A[i, k] = constraint.CombinedAs[j];
b[i] = constraint.Value;
}
else if (constraint.ShouldBe == ConstraintType.LesserThanOrEqualTo)
{
A[i, k] = -constraint.CombinedAs[j];
b[i] = -constraint.Value;
}
else
throw new ArgumentException("The provided constraint type is not supported.");
}
if (constraint.ShouldBe == ConstraintType.EqualTo)
equalities++;
}
return A;
}
