GPIntegrator

How to call it

For using the GPIntegrator class, the developer has only to create such an object with these two possibilities:

• With no initialization:

GPIntegrator gpInteg = new GPIntegrator();

In that case, all the possible integrators will be displayed (i.e. Runge Kutta 4, Runge Kutta 6 and Dormand Price 853)

• Or, if we want to limit the display to some of these integrators (in the example below, only Runge Kutta 4 and Dormand Price 853) and choose the one initially displayes (here the Dormand Price 853 one):

final IntegratorTypeEnum[] types = { IntegratorTypeEnum.RK4, IntegratorTypeEnum.DOP };
GPIntegrator gpInteg = new GPIntegrator(types, IntegratorTypeEnum.DOP);

• There are also several setter methods to override default values. For example, if we want to display by default 5 seconds for the Runge Kutta time steps, we will have to call to the specific method as:

gpInteg.setRKParameters(5.);

Display

For the first cases, the display will be:

as, for the second one …

Note an interesting functionnality for the Dormand Price 853 data with a user help for initializing steps and tolerances depending of some kind of orbits.

How to use it

To get a [PATRIUS] FirstOrderIntegrator object, we will just have to … TBW ...

How it is stored

Here is the XML format for the Dormand Price 853 integrator data:

  <String name="Type:">Dormand-Prince (8th order)</String>
  <Real name="Minimum_timestep:_" unit="s">1.0E0</Real>
  <Real name="Maximum_timestep:_" unit="s">3.0E2</Real>
  <String name="Tolerances_definition:_">Complete</String>
  <Boolean name="Bypass_error_on_min_timestep">true</Boolean>
  <String name="Templates_for_tolerances_definition">---</String>
  <Tolerances name="Tolerance1">
    <Real name="X" unit="m">7.0E-6</Real>
    <Real name="Xr" unit="%">0.0E0</Real>
  </Tolerances>
  <Tolerances name="Tolerance2">
    <Real name="Y" unit="m">7.0E-6</Real>
    <Real name="Yr" unit="%">0.0E0</Real>
  </Tolerances>
  <Tolerances name="Tolerance3">
    <Real name="Z" unit="m">7.0E-6</Real>
    <Real name="Zr" unit="%">0.0E0</Real>
  </Tolerances>
  <Tolerances name="Tolerance4">
    <Real name="Vx" unit="m/s">3.0E-10</Real>
    <Real name="Vxr" unit="%">0.0E0</Real>
  </Tolerances>
  <Tolerances name="Tolerance5">
    <Real name="Vy" unit="m/s">3.0E-10</Real>
    <Real name="Vyr" unit="%">0.0E0</Real>
  </Tolerances>
  <Tolerances name="Tolerance6">
    <Real name="Vz" unit="m/s">3.0E-10</Real>
    <Real name="Vzr" unit="%">0.0E0</Real>
  </Tolerances>
  <Real name="Mass" unit="kg">1.0E-3</Real>
  <Real name="Massr" unit="%">1.0E-2</Real>