Implementation of rollback

[oarcelus]

Hi, I am using unifmu to wrap a solver for PDEs built in python. The python package implements with SUNDIALs IDA solver to solve the equations.

From the description of the tutorials provided in unifmu, it is prety clear how to implement the fmu in basic terms (for co-simulation in my case). I defined the I/O parameters and their types, but I have a doubt on how to implement a rollback mechanism. If I want to connect two FMU's for interoperability, how can I make sure that if a given slave rejects advancing the timestep (because the step is to large or any other reason...) that I can fallback on my previous state? How could I do this with unifmu?

[clagms]

Sounds like you need to implement the set and get state functions on the FMU.

Have you seen this?

unifmu/cli/tests/python_tests/fmu_tests.py

Line 219 in 5c1144a

initial_state = fmu.getFMUstate()

Sorry short answer.