### Question:
PolyUtils { public static DoubleMatrix normalize(DoubleMatrix t) { return t.sub(t.get(t.length / 2)).div(10.0); }  static double normalize2(double data, final int min, final int max); static double normalize2(double data, final double min, final double max); static DoubleMatrix normalize(DoubleMatrix t); static int degreeFromCoefficients(int numOfCoefficients); static int numberOfCoefficients(final int degree); static double[] polyFitNormalized(DoubleMatrix t, DoubleMatrix y, final int degree); static double[] polyFit2D(final DoubleMatrix x, final DoubleMatrix y, final DoubleMatrix z, final int degree); static double[] polyFit(DoubleMatrix t, DoubleMatrix y, final int degree); static double polyVal1D(double x, double[] coeffs); static double[][] polyval(final double[] x, final double[] y, final double coeff[], int degree); static DoubleMatrix polyval(final DoubleMatrix x, final DoubleMatrix y, final DoubleMatrix coeff, int degree); static double polyval(final double x, final double y, final DoubleMatrix coeff, int degree); static double polyval(final double x, final double y, final double[] coeff); static double polyval(final double x, final double y, final double[] coeff, int degree);  }### Answer:
@Test public void testNormalize() throws Exception { double[] array_EXPECTED = {1, 2}; double[] normArray_EXPECTED = {-0.1, 0}; Assert.assertEquals(new DoubleMatrix(normArray_EXPECTED), PolyUtils.normalize(new DoubleMatrix(array_EXPECTED))); }