# Rodas4 vs Rodas4P vs Rodas4P2 solvers

**URL:** <https://discourse.julialang.org/t/rodas4-vs-rodas4p-vs-rodas4p2-solvers/101261>\
**Category:** Modelling & Simulations\
**Tags:** question, modelingtoolkit, differentialequation\
**Created:** [July 6, 2023, 2:13pm UTC](https://discourse.julialang.org/t/rodas4-vs-rodas4p-vs-rodas4p2-solvers/101261 "2023-07-06T14:13:43Z")\
**Posts on this page:** 1\
**Showing post:** 4

<div class="post-metadata">

**Author:** ![Oscar\_Smith](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/oscar_smith/32/25343_2.png) [@Oscar\_Smith](https://discourse.julialang.org/u/Oscar_Smith)\
**Post date:** [July 6, 2023, 3:01pm UTC](https://discourse.julialang.org/t/rodas4-vs-rodas4p-vs-rodas4p2-solvers/101261/4 "2023-07-06T15:01:08Z")

</div>

If you’re using a step input, you should probably be using `tstops` or a `ContinuousCallback` to tell the solver where the discontinuity is (see [Handling Instability When Solving ODE Problems](https://discourse.julialang.org/t/handling-instability-when-solving-ode-problems/9019)).

---

_[View the full topic](https://discourse.julialang.org/t/rodas4-vs-rodas4p-vs-rodas4p2-solvers/101261)._