There was some desire, when allowing a new 'rate of change' construct in http://sourceforge.net/p/sbml/sbml-specifications/212/, to not make things too complicated: 'time' was the only element allowed to differentiate against, and a single 'ci' element was the only allowed argument.
For constant arguments, arguments that appear as the target of a RateRule, and arguments that are Species and appear in Reactions, the rate of change is simple to compute (and indeed, probably is already computed by a simulator).
However, for arguments that are targets of AssignmentRules, or which are calculated by using an AlgebraicRule, the rate of change is a much more complicated thing, and in fact might be arbitrarily complicated if people decide to put rates of change in the AssignmentRules itself. Do we:
1) Disallow targets of AssignmentRules and AlgebraicRules from being the argument of the new 'rate of change' function?
2) Allow it, but warn against it?
3) Allow it?
4) Allow it, and also relax the restriction that the argument of the new 'rate' can only be a 'ci' element?
Log in to post a comment.