The function MarkForDeletion marks or unmarks the particle having the index PartIx to be deleted. Setting the parameter DelMark to TRUE marks the corresponding particle, setting DelMark to FALSE unmarks it. Please note that no actual deletion is taking place. You have to call the method DeleteMarkedParticles to actually remove the marked particles.
The function returns the following error codes:
0 ... everything is OK
-1 ... PartIx was out of range