FirstOrderConverter implements FirstOrderDifferentialEquations { public int getDimension() { return 2 * dimension; } FirstOrderConverter(final SecondOrderDifferentialEquations equations); int getDimension(); void computeDerivatives(final double t, final double[] y, final double[] yDot);  }
@Test public void testDoubleDimension() { for (int i = 1; i < 10; ++i) { SecondOrderDifferentialEquations eqn2 = new Equations(i, 0.2); FirstOrderConverter eqn1 = new FirstOrderConverter(eqn2); Assert.assertTrue(eqn1.getDimension() == (2 * eqn2.getDimension())); } }