FirstOrderDifferentialEquations (Hipparchus 1.4 API)

All Superinterfaces:

OrdinaryDifferentialEquation
```
@Deprecated
public interface FirstOrderDifferentialEquations
extends OrdinaryDifferentialEquation
```
Deprecated.
as of 1.0, replaced with OrdinaryDifferentialEquation

This interface represents a first order differential equations set.
This interface should be implemented by all real first order differential equation problems before they can be handled by the integrators ODEIntegrator.integrate(org.hipparchus.ode.ExpandableODE, org.hipparchus.ode.ODEState, double) method.

A first order differential equations problem, as seen by an integrator is the time derivative dY/dt of a state vector Y, both being one dimensional arrays. From the integrator point of view, this derivative depends only on the current time t and on the state vector Y.

For real problems, the derivative depends also on parameters that do not belong to the state vector (dynamical model constants for example). These constants are completely outside of the scope of this interface, the classes that implement it are allowed to handle them as they want.

See Also:

ODEIntegrator, FirstOrderConverter, SecondOrderDifferentialEquations

Method Summary

All Methods Instance Methods Abstract Methods Default Methods Deprecated Methods
Modifier and Type	Method	Description
`default double[]`	`computeDerivatives(double t, double[] y)`	Deprecated. Get the current time derivative of the state vector.
`void`	`computeDerivatives(double t, double[] y, double[] yDot)`	Deprecated. Get the current time derivative of the state vector.

Methods inherited from interface org.hipparchus.ode.OrdinaryDifferentialEquation
getDimension, init

- Method Detail
  - computeDerivatives
```
default double[] computeDerivatives(double t,
                                    double[] y)
```
    Deprecated.
    
    Get the current time derivative of the state vector.
    The default implementation calls computeDerivatives(double, double[], double[]).
    
    Specified by:
    
    computeDerivatives in interface OrdinaryDifferentialEquation
    
    Parameters:
    
    t - current value of the independent time variable
    
    y - array containing the current value of the state vector
    
    Returns:
    
    time derivative of the state vector
  - computeDerivatives
```
void computeDerivatives(double t,
                        double[] y,
                        double[] yDot)
                 throws MathIllegalArgumentException,
                        MathIllegalStateException
```
    Deprecated.
    
    Get the current time derivative of the state vector.
    
    Parameters:
    
    t - current value of the independent time variable
    
    y - array containing the current value of the state vector
    
    yDot - placeholder array where to put the time derivative of the state vector
    
    Throws:
    
    MathIllegalStateException - if the number of functions evaluations is exceeded
    
    MathIllegalArgumentException - if arrays dimensions do not match equations settings