public void EliminateIdentityEquation()
{
// Arrange
var identityMatrix = new double[, ] {
{ 1, 0, 0 }, { 0, 1, 0 }, { 0, 0, 1 }
};
var coefficients = new double[] { 1, 2, 3 };
// Act
var solution = LU.Eliminate(identityMatrix, coefficients);
// Assert
Assert.AreEqual(coefficients, solution);
}
public void FailOnEliminateEquationWithNonSquareMatrix()
{
// Arrange
var nonSquareMatrix = new double[, ] {
{ 1, 0, 0 }, { 0, 1, 0 }, { 0, 0, 1 }, { 0, 0, 0 }
};
var coefficients = new double[] { 1, 2, 3, 4 };
// Act
void Act(double[,] source, double[] c) => LU.Eliminate(source, c);
// Assert
Assert.Throws <ArgumentException>(() => Act(nonSquareMatrix, coefficients));
}
public void EliminateEquation_Case4X4()
{
// Arrange
var source = new double[, ] {
{ 1.0, 2.0, -3.0, -1.0 }, { 0.0, -3.0, 2.0, 6.0 }, { 0.0, 5.0, -6.0, -2.0 }, { 0.0, -1.0, 8.0, 1.0 }
};
var coefficients = new double[] { 0.0, -8.0, 0.0, -8.0 };
var expectedSolution = new double[] { -1.0, -2.0, -1.0, -2.0 };
// Act
var solution = LU.Eliminate(source, coefficients);
// Assert
Assert.IsTrue(VectorMembersAreEqual(expectedSolution, solution));
}
public void EliminateEquation_Case3X3()
{
// Arrange
var source = new double[, ] {
{ 2, 1, -1 }, { -3, -1, 2 }, { -2, 1, 2 }
};
var coefficients = new double[] { 8, -11, -3 };
var expectedSolution = new double[] { 2, 3, -1 };
// Act
var solution = LU.Eliminate(source, coefficients);
// Assert
Assert.IsTrue(VectorMembersAreEqual(expectedSolution, solution));
}
