5.1. Integrator Settings¶

As the name suggests, the integrator settings tell the dynamics simulator how to integrate numerically the equations of motion that govern the orbital mechanics to simulate. The IntegratorSettings are defined using two derived classes, depending on whether the integrator to be used is a fixed step-size integrator or a variable step-size integrator.

class IntegratorSettings¶

This class is used to define the settings for fixed step-size integration. The constructor for this base class is:

IntegratorSettings( integratorType,
                    simulationStartEpoch,
                    fixedStepSize )

where:

integratorType

AvailableIntegrators which defines the fixed step-size integrator type to be used. Currently the only options available are euler and rungeKutta4.
simulationStartEpoch

double that defines the simulation’s start epoch.
fixedStepSize

double that defines the fixed step-size to be used either by the euler or the rungeKutta4 numerical integrator.

class RungeKuttaVariableStepSizeSettings¶

This class is used to define the settings for variable step-size integration. The constructor for this derived class is:

RungeKuttaVariableStepSizeSettings( integratorType,
                                    initialTime,
                                    initialTimeStep,
                                    coefficientSet,
                                    minimumStepSize,
                                    maximumStepSize )

where:

integratorType

AvailableIntegrators which defines the fixed step-size integrator type to be used. The only option available is rungeKuttaVariableStepSize.
initialTime

double that defines the simulation’s initial time. It must be a double variable-type.
initialTimeStep

double that defines the initial step-size to be used either by the rungeKuttaVariableStepSize numerical integrator. It must be a double variable-type.
coefficientSet

RungeKuttaCoefficients::CoefficientSets that defines the coefficient set to be used by the rungeKuttaVariableStepSize numerical integrator. The list of available coefficient sets is given in Integrators.
minimumStepSize

double that defines the minimum step-size that the rungeKuttaVariableStepSize numerical integrator can take.
maximumStepSize

double that defines the maximum step-size that the rungeKuttaVariableStepSize numerical integrator can take.

Note

Aside from the arguments listed in this page, the IntegratorSettings class and derived classes described here offer a number of optional arguments. The reader is advised to examine the Doxygen documentation included in the code for further details.

Warning

Make sure that a compatible integratorType is selected, otherwise a runtime exception will be thrown.