Julia "no method matching supports_default_copy_to(::GLPK.Optimizer, ::Bool)" 声明模型

Question

我是 Julia 的新手并尝试运行 Second Edition of Julia Programming for Operations Research 中的第一个示例脚本，但前两行：

using JuMP, GLPK
m = Model(with_optimizer(GLPK.Optimizer))

抛出以下错误：

julia> m = Model(with_optimizer(GLPK.Optimizer))
ERROR: MethodError: no method matching supports_default_copy_to(::GLPK.Optimizer, ::Bool)
Closest candidates are:
  supports_default_copy_to(::MathOptInterface.Utilities.AbstractModel, ::Bool) at /home/mepstein/.julia/packages/MathOptInterface/C1XBe/src/Utilities/model.jl:693
  supports_default_copy_to(::MathOptInterface.Utilities.MockOptimizer, ::Bool) at /home/mepstein/.julia/packages/MathOptInterface/C1XBe/src/Utilities/mockoptimizer.jl:521
  supports_default_copy_to(::MathOptInterface.Utilities.CachingOptimizer, ::Bool) at /home/mepstein/.julia/packages/MathOptInterface/C1XBe/src/Utilities/cachingoptimizer.jl:165

如果相关，using JuMP, GLPK 抛出以下 warning：

┌ Warning: Replacing module MathOptInterface
└ @ Base loading.jl:942

我的版本是：

Julia: 1.3.1 (latest stable)
  "GLPK" => v"0.12.0"
  "JuMP" => v"0.20.1"

Answer 1

本书作者在 https://github.com/chkwon/jpor_codes/issues/4

解决了这个问题来自 julia 解释器的

运行 ] up 将 GLPK 从 12.0 升级到 12.1。很有趣，因为几个小时前我刚刚安装了 GLPK。事实上，我什至不确定我 'upgraded' 安装的版本；从日志看来 ] up 使某些配置文件与已安装的版本一致？

julia>
(v1.3) pkg>  up
  Updating registry at `~/.julia/registries/General`
  Updating git-repo `https://github.com/JuliaRegistries/General.git`
 Resolving package versions...
 Installed GLPK ─ v0.12.1
  Updating `~/.julia/environments/v1.3/Project.toml`
  [60bf3e95] ↑ GLPK v0.12.0 ⇒ v0.12.1
  Updating `~/.julia/environments/v1.3/Manifest.toml`
  [60bf3e95] ↑ GLPK v0.12.0 ⇒ v0.12.1
  Building GLPK → `~/.julia/packages/GLPK/HjJiX/deps/build.log`

无论如何，上面问题中的代码现在可以运行并给出以下输出：

julia> using JuMP, GLPK

julia> m = Model(with_optimizer(GLPK.Optimizer))
A JuMP Model
Feasibility problem with:
Variables: 0
Model mode: AUTOMATIC
CachingOptimizer state: EMPTY_OPTIMIZER
Solver name: GLPK```

Julia "no method matching supports_default_copy_to(::GLPK.Optimizer, ::Bool)" 声明模型

Julia "no method matching supports_default_copy_to(::GLPK.Optimizer, ::Bool)" declaring Model

julia

glpk

julia-jump