public void Matrix_MatrixTimesItsInverseTest()
{
Matrix matrix1 = new Matrix(4);
double[] matrix1Column1 = { 1, 5, 6, 7 };
double[] matrix1Column2 = { 2, 4, 7, 6 };
double[] matrix1Column3 = { 3, 6, 8, 7 };
double[] matrix1Column4 = { 7, 6, 8, 7 };
matrix1.SetColumn(0, matrix1Column1);
matrix1.SetColumn(1, matrix1Column2);
matrix1.SetColumn(2, matrix1Column3);
matrix1.SetColumn(3, matrix1Column4);
Matrix expectedResult = Matrix.IdentityMatrix(4);
Matrix actualResult = matrix1 * matrix1.Invert();
bool equalityResult = (actualResult == expectedResult);
equalityResult.Should().BeTrue();
}
public void Matrix_InvertTest()
{
Matrix matrix1 = new Matrix(3,3);
double[] matrix1Column1 = { 1, 5, 6 };
double[] matrix1Column2 = { 2, 4, 7 };
double[] matrix1Column3 = { 3, 6, 8 };
matrix1.SetColumn(0, matrix1Column1);
matrix1.SetColumn(1, matrix1Column2);
matrix1.SetColumn(2, matrix1Column3);
Matrix expectedResult = new Matrix(3,3);
double[] expectedResultColumn1 = { (double)-2 / 3, (double)-4 / 15, (double)11 / 15 };
double[] expectedResultColumn2 = { (double)1 / 3, (double)-2 / 3, (double)1 / 3 };
double[] expectedResultColumn3 = { (double)0, (double)3 / 5, (double)-2 / 5 };
expectedResult.SetColumn(0, expectedResultColumn1);
expectedResult.SetColumn(1, expectedResultColumn2);
expectedResult.SetColumn(2, expectedResultColumn3);
Matrix actualResult = matrix1.Invert();
bool equalityResult = (actualResult == expectedResult);
equalityResult.Should().BeTrue();
}