class CholeskyDecomposition {

    public RealMatrix getL() {
        if (cachedL == null) {
            cachedL = getLT().transpose();
        }
        return cachedL;
    }

    public  CholeskyDecomposition(final RealMatrix matrix);
    public  CholeskyDecomposition(final RealMatrix matrix,
                                     final double relativeSymmetryThreshold,
                                     final double absolutePositivityThreshold);

}