public void doWork()
{
matrix.Fill((j, i) => array[i, j]);
SquareQRDecomposition qr = matrix.QRDecomposition();
SquareLUDecomposition lu = matrix.LUDecomposition();
ColumnVector qrresult = qr.Solve(vector);
ColumnVector luresult = lu.Solve(vector);
ColumnVector c6 = matrix.Column(6);
RowVector r2 = matrix.Row(2);
SquareMatrix inv = matrix.Inverse();
ColumnVector result = new ColumnVector(inv.Dimension);
for (int i = 0; i < matrix.Dimension; ++i)
{
for (int j = 0; j < matrix.Dimension; ++j)
{
result[i] += matrix[i, j] * qrresult[j];
}
}
}