NFSim immediately creates an observable for total in a default compartment when molecule created

[ACowan0105]

May need to clarify issue

[jcschaff]

I suppose that this is not desirable? @vcellmike @danv61 Please explain how vcell behaves now, and what you would like it to do.

[danv61]

@jcschaff This observable was initially created when we were dealing with single compartment models. It allowed us to verify mass conservation, which allowed us to fix some very nasty early bugs. For multi-compartment models the observable we make should be the sum of the totals for all compartments, not just one. We never intended to overcomplicate this, like maintaining the expression when compartments are being added or deleted. Look at it as a debugging tool / feature.