# Pkg update downgrade JuMP

**URL:** <https://discourse.julialang.org/t/pkg-update-downgrade-jump/27621>\
**Category:** Optimization (Mathematical)\
**Tags:** jump, pkg, update\
**Created:** [August 16, 2019, 5:00pm UTC](https://discourse.julialang.org/t/pkg-update-downgrade-jump/27621 "2019-08-16T17:00:48Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![remi-garcia](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/remi-garcia/32/7125_2.png) [@remi-garcia](https://discourse.julialang.org/u/remi-garcia)\
**Post date:** [August 16, 2019, 5:00pm UTC](https://discourse.julialang.org/t/pkg-update-downgrade-jump/27621/1 "2019-08-16T17:00:48Z")

</div>

Hi,

When I add JuMP and GLPK I get this:

```nohighlight
(v1.1) pkg> st
    Status `~/.julia/environments/v1.1/Project.toml`
  (empty environment)

(v1.1) pkg> add JuMP GLPK
 Resolving package versions...
  Updating `~/.julia/environments/v1.1/Project.toml`
  [60bf3e95] + GLPK v0.11.0
  [4076af6c] + JuMP v0.18.6
  Updating `~/.julia/environments/v1.1/Manifest.toml`
  ...

```

When I add JuMP I have the latest version of JuMP, if I add GLPK and update I get this:

```nohighlight
(v1.1) pkg> st
   Status `~/.julia/environments/v1.1/Project.toml`
 (empty environment)

(v1.1) pkg> add JuMP
Resolving package versions...
 Updating `~/.julia/environments/v1.1/Project.toml`
 [4076af6c] + JuMP v0.19.2
 Updating `~/.julia/environments/v1.1/Manifest.toml`
 ...

(v1.1) pkg> add GLPK
Resolving package versions...
 Updating `~/.julia/environments/v1.1/Project.toml`
 [60bf3e95] + GLPK v0.10.0
 Updating `~/.julia/environments/v1.1/Manifest.toml`
 [60bf3e95] + GLPK v0.10.0
 [f8899e07] + LinQuadOptInterface v0.6.0

(v1.1) pkg> update
 Updating registry at `~/.julia/registries/General`
 Updating git-repo `https://github.com/JuliaRegistries/General.git`
Resolving package versions...
 Updating `~/.julia/environments/v1.1/Project.toml`
 [60bf3e95] ↑ GLPK v0.10.0 ⇒ v0.11.0
 [4076af6c] ↓ JuMP v0.19.2 ⇒ v0.18.6
 Updating `~/.julia/environments/v1.1/Manifest.toml`
 [6e4b80f9] + BenchmarkTools v0.4.2
 [60bf3e95] ↑ GLPK v0.10.0 ⇒ v0.11.0
 [682c06a0] + JSON v0.21.0
 [4076af6c] ↓ JuMP v0.19.2 ⇒ v0.18.6
 [f8899e07] - LinQuadOptInterface v0.6.0
 [b8f27783] ↑ MathOptInterface v0.8.4 ⇒ v0.9.0
 [fdba3010] + MathProgBase v0.7.7
 [69de0a69] + Parsers v0.3.6
 [89212889] + ReverseDiffSparse v0.8.6

```

That doesn’t seems normal. I want the latest version of JuMP, how can I do that? Should I pin it before any update?

---

<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:** [August 16, 2019, 6:15pm UTC](https://discourse.julialang.org/t/pkg-update-downgrade-jump/27621/2 "2019-08-16T18:15:49Z")

</div>

It seems to be a pug in Pkg. It shouldn’t downgrade a package to be able to upgrade another one.  
You should either pin GLPK at v0.10 or pin JuMP at v0.19.2 or pin JuMP at this branch: [https://github.com/JuliaOpt/JuMP.jl/pull/2003](https://github.com/JuliaOpt/JuMP.jl/pull/2003)

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<div class="post-metadata">

**Author:** ![kristoffer.carlsson](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/kristoffer.carlsson/32/22_2.png) [@kristoffer.carlsson](https://discourse.julialang.org/u/kristoffer.carlsson)\
**Post date:** [August 16, 2019, 7:02pm UTC](https://discourse.julialang.org/t/pkg-update-downgrade-jump/27621/3 "2019-08-16T19:02:10Z")

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> [@remi-garcia](#):
>
> That doesn’t seems normal. I want the latest version of JuMP, how can I do that?

Put

```julia
[compat]
JuMP = "0.19"

```

in your project file. The fact that it isn’t there now means that you are as happy with JuMP at 0.18 as 0.19.

---

<div class="post-metadata">

**Author:** ![remi-garcia](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/remi-garcia/32/7125_2.png) [@remi-garcia](https://discourse.julialang.org/u/remi-garcia)\
**Post date:** [August 17, 2019, 3:11pm UTC](https://discourse.julialang.org/t/pkg-update-downgrade-jump/27621/4 "2019-08-17T15:11:53Z")

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Thank you both for your answers. I’ll make this change in my project file then.