Can you share the file of this sim? ... I'd like to play with it a bit, if you don't mind.

Only last sim, because I did not save previous.
Change extention of file from PDF to VMG.
Edit:

 

Only last sim, because I did not save previous.
Change extention of file from PDF to VMG.

Seems it should be 3 files complete:

 

ViziMag.
Important curve.
Exact sine.
It will symmetrical when even number of magnet pairs will closed in loop.