### Question:
LUDecompositionCommonsResult implements LUDecompositionResult { @Override public DoubleMatrix getL() { return _l; } LUDecompositionCommonsResult(LUDecomposition lu); @Override double getDeterminant(); @Override DoubleMatrix getL(); @Override DoubleMatrix getP(); @Override int[] getPivot(); @Override DoubleMatrix getU(); @Override DoubleArray solve(DoubleArray b); @Override double[] solve(double[] b); @Override DoubleMatrix solve(DoubleMatrix b);  }### Answer:
@Test public void testGetL() { double[][] expectedRaw = new double[][] { {1.0000000000000000, 0.0000000000000000, 0.0000000000000000, 0.0000000000000000}, {0.0900000000000000, 1.0000000000000000, 0.0000000000000000, 0.0000000000000000}, {0.1000000000000000, 0.2053262858304534, 1.0000000000000000, 0.0000000000000000}, {0.0800000000000000, 0.1886562309412482, 0.6500406024227509, 1.0000000000000000}}; assertThat(FuzzyEquals.ArrayFuzzyEquals(RESULT.getL().toArray(), expectedRaw)).isTrue(); }