From a quick look, it seems a modelling problem. It's basically asking "what is the best function with this properties". Where the meaning of 'best' is far from clear. Essentially, a function that does what I want with the data I have. It's not a technology problem.
It could be argued that this specific question needs to be closed with both the too broad and unclear what you are asking reasons, but a better point to discuss here is whether modelling questions are ok on MO.
People have discussed this topic at math.stackexchange, and proposed to open a new SE site (the proposal wasn't successful and has now been deleted).
I see three possible answers:
This kind of questions is off-topic here. Until there is no mathmodelling.stackexchange.com, they live in the "stack exchange limbo" where there is no SE site available for them.
This kind of question is officially on topic here. We don't want yet another math-related SE site, and the borders between the two disciplines are blurry anyway. Let's modify the site policies.
This kind of questions is a better fit for http://scicomp.stackexchange.com, because they are more linked to computational/applied side of mathematics than to the pure discipline. We can migrate them manually. If compsci.SE (which is still in beta) closes,
It is ultimately a political decision, "what do we want this site to be". All choices have their pros and cons. My understanding is that the common consensus among the Mathoverflow moderators and high-rep users is more towards 3.