Computational graph can represent expressions as graphs. For example, `a+b`

can be represented like the above figure. When we consider an expression with self-feedback, how can it be represented as a graph? For example, `dv(t)/dt=v(t)+i(t)`

can be solved as `v(t)=v(t-1)f(t)+i(t)`

. It is possible to construct a graph with right-hand side. But, we also have to store the final result to a state variable `v`

. How to handle this issue?

Thank you.