This is a Python related question. If you assign a new variable to the Python object f_prev, by equality:
You need to redefine objects using f_prev.
If you use
f_prev.t=t
f_prev.u=u_prev
You do not Need to define the variational forms
This is a Python related question. If you assign a new variable to the Python object f_prev, by equality:
You need to redefine objects using f_prev.
If you use
f_prev.t=t
f_prev.u=u_prev
You do not Need to define the variational forms