# Can't get the same results at the rocket control tutorial in JuMP

**URL:** <https://discourse.julialang.org/t/cant-get-the-same-results-at-the-rocket-control-tutorial-in-jump/61235>\
**Category:** Optimization (Mathematical)\
**Tags:** question, package, jump, tutorials\
**Created:** [May 16, 2021, 8:14am UTC](https://discourse.julialang.org/t/cant-get-the-same-results-at-the-rocket-control-tutorial-in-jump/61235 "2021-05-16T08:14:45Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![yucho147](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/yucho147/32/25135_2.png) [@yucho147](https://discourse.julialang.org/u/yucho147)\
**Post date:** [May 16, 2021, 8:14am UTC](https://discourse.julialang.org/t/cant-get-the-same-results-at-the-rocket-control-tutorial-in-jump/61235/1 "2021-05-16T08:14:45Z")

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Hi  
I am learning how to use the JuMP package. However, I am not getting the same results from the rocket control tutorial.  
[https://jump.dev/JuMP.jl/v0.21.8/tutorials/Nonlinear%20programs/rocket\_control/](https://jump.dev/JuMP.jl/v0.21.8/tutorials/Nonlinear%20programs/rocket_control/)  
In my environment, I get the following results.

 ![スクリーンショット 2021-05-16 17.11.55](https://global.discourse-cdn.com/julialang/original/3X/7/5/75de6dc5263d782cf51fdf2ea429748afd65a8ba.jpeg)

Is there any problem?

* * *

My environment…  
Julia Version 1.6.1  
Platform Info:  
OS: macOS (x86\_64-apple-darwin18.7.0)  
CPU: Intel(R) Core™ i5-7360U CPU @ 2.30GHz  
WORD\_SIZE: 64  
LIBM: libopenlibm  
LLVM: libLLVM-11.0.1 (ORCJIT, skylake)

Ipopt v0.6.3  
JuMP v0.21.8

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<div class="post-metadata">

**Author:** ![blegat](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/blegat/32/217090_2.png) [@blegat](https://discourse.julialang.org/u/blegat)\
**Post date:** [May 16, 2021, 11:30am UTC](https://discourse.julialang.org/t/cant-get-the-same-results-at-the-rocket-control-tutorial-in-jump/61235/2 "2021-05-16T11:30:06Z")

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Can you give us what [`solution_summary`](https://jump.dev/JuMP.jl/v0.21.8/reference/solutions/#JuMP.solution_summary) is ? In particular, what’s the solution status ?

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<div class="post-metadata">

**Author:** ![yucho147](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/yucho147/32/25135_2.png) [@yucho147](https://discourse.julialang.org/u/yucho147)\
**Post date:** [May 16, 2021, 12:05pm UTC](https://discourse.julialang.org/t/cant-get-the-same-results-at-the-rocket-control-tutorial-in-jump/61235/3 "2021-05-16T12:05:31Z")

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Thank you for your reply

I get following,

```julia
julia> solution_summary(rocket)
* Solver : Ipopt

* Status
  Termination status : NUMERICAL_ERROR
  Primal status : UNKNOWN_RESULT_STATUS
  Dual status : UNKNOWN_RESULT_STATUS
  Message from the solver:
  "Restoration_Failed"

* Candidate solution
  Objective value : 1.0099999899999998

* Work counters
  Solve time (sec) : 2.95176

```

I just started using the JuMP package and there are many things I don’t understand.  
I noticed that I am getting an error only by running the above.  
What is the cause of this error?  
I apologize for any inconvenience.

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**Author:** ![odow](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/odow/32/28685_2.png) [@odow](https://discourse.julialang.org/u/odow)\
**Post date:** [May 16, 2021, 9:46pm UTC](https://discourse.julialang.org/t/cant-get-the-same-results-at-the-rocket-control-tutorial-in-jump/61235/4 "2021-05-16T21:46:23Z")

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Update to Ipopt v0.6.5. For a short time there was an issue with the linear solver in Ipopt that caused issues like this.

```nohighlight
] add Ipopt@0.6.5

```

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<div class="post-metadata">

**Author:** ![yucho147](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/yucho147/32/25135_2.png) [@yucho147](https://discourse.julialang.org/u/yucho147)\
**Post date:** [May 17, 2021, 12:08am UTC](https://discourse.julialang.org/t/cant-get-the-same-results-at-the-rocket-control-tutorial-in-jump/61235/5 "2021-05-17T00:08:35Z")

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Thank you for your quick response!! @odow @blegat !!  
After updating the package, I got the same result as in the tutorial.