public void MatrixComputationsEigenvaluesTest()
{
// first matrix
Matrix matrix = new Matrix(new[, ] {
{ 5, 4, 1.3 }, { 4, 8.7, 2 }, { 1.3, 2, 0 }
});
Double[] expected = new Double[3] {
11.7417, 2.44301, -0.484678
};
Double[] result = MatrixComputations.Eigenvalues(matrix);
Array.Sort(expected);
Array.Sort(result);
result.Length.ShouldBe(expected.Length);
for (Int32 index = 0; index < result.Length; index++)
{
result[index].ShouldBe(expected[index], 0.001);
}
// second matrix
matrix = new Matrix(new[, ] {
{ 5, 8, 7.6, 2 }, { 8, 42, 0, 1 }, { 7.6, 0, 3, 5 }, { 2, 1, 5, 22.4 }
});
expected = new Double[4] {
43.8386, 24.094, 8.97766, -4.51021
};
result = MatrixComputations.Eigenvalues(matrix);
Array.Sort(expected);
Array.Sort(result);
result.Length.ShouldBe(expected.Length);
for (Int32 index = 0; index < result.Length; index++)
{
result[index].ShouldBe(expected[index], 0.001);
}
// identity matrix
matrix = MatrixFactory.CreateIdentity(4);
expected = new Double[4] {
1, 1, 1, 1
};
result = MatrixComputations.Eigenvalues(matrix);
Array.Sort(expected);
Array.Sort(result);
result.Length.ShouldBe(expected.Length);
for (Int32 index = 0; index < result.Length; index++)
{
result[index].ShouldBe(expected[index], 0.001);
}
// exceptions
Should.Throw <ArgumentNullException>(() => MatrixComputations.Eigenvalues(null));
}
