Real-time input and plotting with ModelingToolkit

Specific Domains Modelling & Simulations
8

This was working fine for a while, but after reformulating my model I’m now hitting return codes of Unstable. To be clear, I’ve got a loop like

my_value = 10
read_my_value(t) = my_value
@register_symbolic read_my_value(t)
while true
    step!(integrator, dt, true)
    my_value += 1   # super-simplified; in reality it's a GUI slider
end

I read the PSA and this part:

Double check if you’re doing anything that violates assumptions of being an ODE. As an ODE, the right-hand side f function should always give you the same result: u' = f(u,p,t) needs to be uniquely defined. These issues are just fundamental to the mathematics: if you do these things in f , then f no longer defines an ODE so of course it cannot be solved!

makes me worry that maybe step! can go before the current time t and get upset that f(t-1) no longer returns the value it did before.