# How to remake a SteadyStateProblem efficiently

**URL:** <https://discourse.julialang.org/t/how-to-remake-a-steadystateproblem-efficiently/130376>\
**Category:** Modelling & Simulations\
**Created:** [July 1, 2025, 3:43pm UTC](https://discourse.julialang.org/t/how-to-remake-a-steadystateproblem-efficiently/130376 "2025-07-01T15:43:27Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Bart\_van\_de\_Lint](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/bart_van_de_lint/32/212161_2.png) [@Bart\_van\_de\_Lint](https://discourse.julialang.org/u/Bart_van_de_Lint)\
**Post date:** [July 1, 2025, 3:43pm UTC](https://discourse.julialang.org/t/how-to-remake-a-steadystateproblem-efficiently/130376/1 "2025-07-01T15:43:27Z")

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I am trying to efficiently reinitialize a SteadyStateProblem, built from a ModelingToolkit `System`.

```julia
steady_prob = SteadyStateProblem(prob)
steady_prob = remake(steady_prob; u0=new_u0)

```

But this doesn’t actually change the u0 of the problem. What would be the correct way to update the state? It has to be efficient, so either using `setsym` or preferably by providing u0 directly.

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**Author:** ![Sushrut\_Deshpande](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sushrut_deshpande/32/52754_2.png) [@Sushrut\_Deshpande](https://discourse.julialang.org/u/Sushrut_Deshpande)\
**Post date:** [July 1, 2025, 3:49pm UTC](https://discourse.julialang.org/t/how-to-remake-a-steadystateproblem-efficiently/130376/2 "2025-07-01T15:49:35Z")

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This is not the solution to your problem but for me the `remake` works as expected for `NonlinearProblem`. It does not work for `SteadyStateProblem`

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<div class="post-metadata">

**Author:** ![Bart\_van\_de\_Lint](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/bart_van_de_lint/32/212161_2.png) [@Bart\_van\_de\_Lint](https://discourse.julialang.org/u/Bart_van_de_Lint)\
**Post date:** [July 1, 2025, 6:11pm UTC](https://discourse.julialang.org/t/how-to-remake-a-steadystateproblem-efficiently/130376/3 "2025-07-01T18:11:28Z")

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Figured it out. I was providing defaults while building the problem, which were overriding the `Initial` values I was providing when reinitializing.