RC3BP: Restricted Circular 3 Body Problem.
@alainm : it seems to me we didn't introduce this option in frame, not important immediately, I open this issue to remember after the holidays ..
this is the drift of the planet after 4 orbits only, not dramatic but
there are cases in which we really want the planet to remain in (x,y)=(1,0)
precisely when we use nonuniform grid (in the future nested grid)
Just to recall: when we have 1 planet alone and the planet is on a circular planar orbit we ask for Referential Type Constant, Omega == The Keplerian Omega of the planet
The aim is to have the planet "fixed" usually at gridcell crossing
however numerical error are such that the planet is drifting
in the old (svn version) we obtained a fixed planet with an option Fixed that:
- did not call the Runge Kunta (which works on fixed frame)
- did not call the rotation of -\OmegaFrame dt