/// <summary> /// Solves a set of coupled, conservative second order ordinary differential equation initial value problems using the given settings. /// </summary> /// <param name="rhs">The right hand side function.</param> /// <param name="x0">The initial value of the independent variable.</param> /// <param name="y0">The initial values of the functions.</param> /// <param name="yPrime0">The intial values of the functions' derivatives.</param> /// <param name="x1">The final value of the independent variable.</param> /// <param name="settings">The settings to use when solving the problem.</param> /// <returns>The solution, including the final value of the functions and their derivatives.</returns> /// <exception cref="ArgumentNullException"><paramref name="rhs"/>, <paramref name="y0"/>, <paramref name="yPrime0"/>, /// or <paramref name="settings"/> is <see langword="null"/>.</exception> /// <exception cref="DimensionMismatchException"><paramref name="y0"/> and <paramref name="yPrime0"/> do not have the same /// dimension.</exception> /// <exception cref="NonconvergenceException">The ODE could not be integrated to the required precision before exhausting /// the maximum allowed number of <paramref name="rhs"/>evaluations.</exception> /// <remarks> /// <para>For information on conservative ODEs, see <see cref="FunctionMath.IntegrateConservativeOde(Func{double, double, double}, double, double, double, double, OdeEvaluationSettings)"/>.</para> /// </remarks> public static MultiOdeResult IntegrateConservativeOde(Func <double, IList <double>, IList <double> > rhs, double x0, IList <double> y0, IList <double> yPrime0, double x1, MultiOdeEvaluationSettings settings) { if (rhs == null) { throw new ArgumentNullException(nameof(rhs)); } if (y0 == null) { throw new ArgumentNullException(nameof(y0)); } if (yPrime0 == null) { throw new ArgumentNullException(nameof(yPrime0)); } if (settings == null) { throw new ArgumentNullException(nameof(settings)); } if (y0.Count != yPrime0.Count) { throw new DimensionMismatchException(); } FunctionMath.SetOdeDefaults(settings); MultiStoermerEngine engine = new MultiStoermerEngine(rhs, x0, y0, yPrime0, settings); BulrischStoerStrategy strategy = new BulrischStoerStrategy(engine); strategy.IntegrateTo(x1); return(engine.GetResult()); }
/// <summary> /// Solves a set of coupled ordinary differential equation initial value problems. /// </summary> /// <param name="rhs">The right hand side function, which returns the value of the derivative given /// the values of the independent variable and the function.</param> /// <param name="x0">The initial value of the independent variable.</param> /// <param name="y0">The initial value of the function.</param> /// <param name="x1">The final value of the independent variable.</param> /// <param name="settings">The settings to use when solving the problem.</param> /// <returns>The solution, including the final value of the function and its derivative.</returns> /// <exception cref="ArgumentNullException"><paramref name="rhs"/>, <paramref name="y0"/>, or <paramref name="settings"/> /// is <see langword="null"/>.</exception> /// <exception cref="NonconvergenceException">The ODE could not be integrated to the required precision before exhausting /// the maximum allowed number of <paramref name="rhs"/>evaluations.</exception> /// <remarks> /// <para>This method integrates a set of coupled ordinary differential equations. The dependent variable y is a vector /// with any number of components, and the right-hand-side is a vector-valued function that gives the derivative /// of each component. Each component's derivative may depend itself and any other components, as well as on the independent variable. /// The independent variable x still takes only a single real value.</para> /// </remarks> public static MultiOdeResult IntegrateOde(Func <double, IReadOnlyList <double>, IReadOnlyList <double> > rhs, double x0, IReadOnlyList <double> y0, double x1, MultiOdeSettings settings) { if (rhs == null) { throw new ArgumentNullException(nameof(rhs)); } if (y0 == null) { throw new ArgumentNullException(nameof(y0)); } if (settings == null) { throw new ArgumentNullException(nameof(settings)); } FunctionMath.SetOdeDefaults(settings); MultiBulrischStoerEngine engine = new MultiBulrischStoerEngine(rhs, x0, y0, settings); BulrischStoerStrategy strategy = new BulrischStoerStrategy(engine); strategy.IntegrateTo(x1); return(engine.GetResult()); }