# DiffEqFlux.sciml\_train giving UndefVarError: ProgressLogging not defined

**URL:** <https://discourse.julialang.org/t/diffeqflux-sciml-train-giving-undefvarerror-progresslogging-not-defined/45478>\
**Category:** General Usage\
**Tags:** error\
**Created:** [August 24, 2020, 11:26pm UTC](https://discourse.julialang.org/t/diffeqflux-sciml-train-giving-undefvarerror-progresslogging-not-defined/45478 "2020-08-24T23:26:53Z")\
**Posts on this page:** 8\
**Page:** 1

<div class="post-metadata">

**Author:** ![anon22248738](https://avatars.discourse-cdn.com/v4/letter/a/f05b48/32.png) [@anon22248738](https://discourse.julialang.org/u/anon22248738)\
**Post date:** [August 24, 2020, 11:26pm UTC](https://discourse.julialang.org/t/diffeqflux-sciml-train-giving-undefvarerror-progresslogging-not-defined/45478/1 "2020-08-24T23:26:53Z")

</div>

When running the Optimization of Ordinary Differential Equations tutorial in the DiffEqFlux documentation, I get the following error

```julia
ERROR: LoadError: UndefVarError: ProgressLogging not defined
Stacktrace:
 [1] default_logger(::Atom.Progress.JunoProgressLogger) at C:\Users\jmurp\.julia\packages\DiffEqBase\VoY3t\src\utils.jl:262
 [2] sciml_train(::Function, ::Array{Float64,1}, ::ADAM, ::Base.Iterators.Cycle{Tuple{DiffEqFlux.NullData}}; cb::Function, maxiters::Int64, progress::Bool, save_best::Bool) at C:\Users\jmurp\.julia\packages\DiffEqFlux\FZMwP\src\train.jl:42
 [3] top-level scope at C:\Users\jmurp\OneDrive\Desktop\Research\AstroML\Julia\DiffEqFluxTutorials.jl:45
 [4] include_string(::Function, ::Module, ::String, ::String) at .\loading.jl:1088
in expression starting at C:\Users\jmurp\OneDrive\Desktop\Research\AstroML\Julia\DiffEqFluxTutorials.jl:45

```

My code is identical to the tutorial

```julia
using DifferentialEquations, Flux, Optim, DiffEqFlux, DiffEqSensitivity, Plots

function lotka_volterra!(du, u, p, t)
    x, y = u
    α, Β, δ, γ = p
    du[1] = dx = α * x - Β * x * y
    du[2] = dy = -δ * y + γ * x * y
end

# Initial Condition
u0 = [1.0, 1.0]

# Simulation Interval and Intermediary Points
tspan = (0.0, 10.0)
tsteps = 0.0:0.1:10.0

# LV parameter p = [α, β, δ, γ]
p = [1.5, 1.0, 3.0, 1.0]

# Setup and Solve the ODE Problem
prob = ODEProblem(lotka_volterra!, u0, tspan, p)
sol = solve(prob, Tsit5())

# Plot the Solution
plot(sol)
savefig("LV_ode.png")

function loss(p)
    sol = solve(prob, Tsit5(), p = p, saveat = tsteps)
    loss = sum(abs2, sol .- 1)
    return loss, sol
end

callback = function (p, l, pred)
    display(l)
    plt = plot(pred, ylim = (0, 6))
    display(plt)
    # Tell sciml_train to not halt the optimization. If return true, then
    # optimization stops.
    return false
end

result_ode = DiffEqFlux.sciml_train(loss, p,
                                    ADAM(0.1),
                                    cb = callback,
                                    maxiters = 100)

```

My code is runniing on Julia 1.5.0 and my package statuses are :  
DifferentialEquations v6.15.0  
Flux v0.10.4  
Optim v0.21.0  
DiffEqFlux v1.17.0  
DiffEqSensitivity v6.31.1  
Plots v1.6.0

I’ve tried restarting Julia and Atom and building ProgressLogging locally.

---

<div class="post-metadata">

**Author:** ![ChrisRackauckas](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/chrisrackauckas/32/77_2.png) [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)\
**Post date:** [August 25, 2020, 2:08am UTC](https://discourse.julialang.org/t/diffeqflux-sciml-train-giving-undefvarerror-progresslogging-not-defined/45478/2 "2020-08-25T02:08:03Z")

</div>

This was an error in the latest release. Sorry. I fixed this up with the release of DiffEqFlux v1.21.0

---

<div class="post-metadata">

**Author:** ![matias](https://avatars.discourse-cdn.com/v4/letter/m/7ea924/32.png) [@matias](https://discourse.julialang.org/u/matias)\
**Post date:** [August 25, 2020, 3:51pm UTC](https://discourse.julialang.org/t/diffeqflux-sciml-train-giving-undefvarerror-progresslogging-not-defined/45478/3 "2020-08-25T15:51:11Z")

</div>

Got the same error. when I try to download the lastest version of DiffEqFlux i get this compatibility issue…

(@JuliaPro\_v1.5.0-1) pkg\> add [https://github.com/SciML/DiffEqFlux.jl](https://github.com/SciML/DiffEqFlux.jl)  
Updating git-repo `https://github.com/SciML/DiffEqFlux.jl`  
Resolving package versions…  
ERROR: Unsatisfiable requirements detected for package Adapt [79e6a3ab]:  
Adapt [79e6a3ab] log:  
├─possible versions are: [0.3.0-0.3.1, 0.4.0-0.4.2, 1.0.0-1.0.1, 1.1.0, 2.0.0-2.0.2] or uninstalled  
├─restricted to versions 1-2 by DiffEqFlux [aae7a2af], leaving only versions [1.0.0-1.0.1, 1.1.0, 2.0.0-2.0.2]  
│ └─DiffEqFlux [aae7a2af] log:  
│ ├─possible versions are: 1.21.0 or uninstalled  
│ └─DiffEqFlux [aae7a2af] is fixed to version 1.21.0  
├─restricted by compatibility requirements with CuArrays [3a865a2d] to versions: [1.0.0-1.0.1, 1.1.0]  
│ └─CuArrays [3a865a2d] log:  
│ ├─possible versions are: [0.2.1, 0.3.0, 0.4.0, 0.5.0, 0.6.0-0.6.2, 0.7.0-0.7.3, 0.8.0-0.8.1, 0.9.0-0.9.1, 1.0.0-1.0.2, 1.1.0, 1.2.0-1.2.1, 1.3.0, 1.4.0-1.4.7, 1.5.0, 1.6.0, 1.7.0-1.7.3, 2.0.0-2.0.1, 2.1.0, 2.2.0-2.2.2] or uninstalled  
│ ├─restricted to versions \* by an explicit requirement, leaving only versions [0.2.1, 0.3.0, 0.4.0, 0.5.0, 0.6.0-0.6.2, 0.7.0-0.7.3, 0.8.0-0.8.1, 0.9.0-0.9.1, 1.0.0-1.0.2, 1.1.0, 1.2.0-1.2.1, 1.3.0, 1.4.0-1.4.7, 1.5.0, 1.6.0, 1.7.0-1.7.3, 2.0.0-2.0.1, 2.1.0, 2.2.0-2.2.2]  
│ ├─restricted by compatibility requirements with GPUArrays [0c68f7d7] to versions: [0.2.1, 2.0.0-2.0.1, 2.1.0, 2.2.0-2.2.2] or uninstalled, leaving only versions: [0.2.1, 2.0.0-2.0.1, 2.1.0, 2.2.0-2.2.2]  
│ │ └─GPUArrays [0c68f7d7] log:  
│ │ ├─possible versions are: [0.3.0-0.3.4, 0.4.0-0.4.2, 0.5.0, 0.6.0-0.6.1, 0.7.0-0.7.2, 1.0.0-1.0.4, 2.0.0-2.0.1, 3.0.0-3.0.1, 3.1.0, 3.2.0, 3.3.0, 3.4.0-3.4.1, 4.0.0-4.0.1, 5.0.0, 5.1.0] or uninstalled  
│ │ ├─restricted to versions \* by an explicit requirement, leaving only versions [0.3.0-0.3.4, 0.4.0-0.4.2, 0.5.0, 0.6.0-0.6.1, 0.7.0-0.7.2, 1.0.0-1.0.4, 2.0.0-2.0.1, 3.0.0-3.0.1, 3.1.0, 3.2.0, 3.3.0, 3.4.0-3.4.1, 4.0.0-4.0.1, 5.0.0, 5.1.0]  
│ │ ├─restricted by compatibility requirements with CUDA [052768ef] to versions: [3.4.0-3.4.1, 4.0.0-4.0.1, 5.0.0, 5.1.0]  
│ │ │ └─CUDA [052768ef] log:  
│ │ │ ├─possible versions are: [0.1.0, 1.0.0-1.0.2, 1.1.0, 1.2.0-1.2.1, 1.3.0-1.3.3] or uninstalled  
│ │ │ ├─restricted to versions \* by an explicit requirement, leaving only versions [0.1.0, 1.0.0-1.0.2, 1.1.0, 1.2.0-1.2.1, 1.3.0-1.3.3]  
│ │ │ └─restricted by compatibility requirements with Flux [587475ba] to versions: [1.0.0-1.0.2, 1.1.0, 1.2.0-1.2.1, 1.3.0-1.3.3]  
│ │ │ └─Flux [587475ba] log:  
│ │ │ ├─possible versions are: [0.4.1, 0.5.0-0.5.4, 0.6.0-0.6.10, 0.7.0-0.7.3, 0.8.0-0.8.3, 0.9.0, 0.10.0-0.10.4, 0.11.0-0.11.1] or uninstalled  
│ │ │ └─restricted to versions 0.11 by DiffEqFlux [aae7a2af], leaving only versions 0.11.0-0.11.1  
│ │ │ └─DiffEqFlux [aae7a2af] log: see above  
│ │ └─restricted by compatibility requirements with CuArrays [3a865a2d] to versions: [3.1.0, 3.2.0, 3.3.0, 3.4.0-3.4.1], leaving only versions: 3.4.0-3.4.1  
│ │ └─CuArrays [3a865a2d] log: see above  
│ └─restricted by compatibility requirements with CUDAdrv [c5f51814] to versions: [0.4.0, 0.5.0, 0.6.0-0.6.2, 0.7.0-0.7.3, 0.8.0-0.8.1, 1.0.2, 1.1.0, 1.2.0-1.2.1, 1.3.0, 1.4.0-1.4.7, 1.5.0, 1.6.0, 1.7.0-1.7.3, 2.0.0-2.0.1, 2.1.0, 2.2.0-2.2.2] or uninstalled, leaving only versions: [2.0.0-2.0.1, 2.1.0, 2.2.0-2.2.2]  
│ └─CUDAdrv [c5f51814] log:  
│ ├─possible versions are: [0.8.0-0.8.6, 0.9.0, 1.0.0-1.0.1, 2.0.0, 3.0.0-3.0.1, 3.1.0, 4.0.0-4.0.4, 5.0.0-5.0.1, 5.1.0, 6.0.0-6.0.1, 6.1.0, 6.2.0-6.2.3, 6.3.0] or uninstalled  
│ ├─restricted to versions \* by an explicit requirement, leaving only versions [0.8.0-0.8.6, 0.9.0, 1.0.0-1.0.1, 2.0.0, 3.0.0-3.0.1, 3.1.0, 4.0.0-4.0.4, 5.0.0-5.0.1, 5.1.0, 6.0.0-6.0.1, 6.1.0, 6.2.0-6.2.3, 6.3.0]  
│ ├─restricted by compatibility requirements with CUDAnative [be33ccc6] to versions: [0.8.0-0.8.6, 3.0.0-3.0.1, 3.1.0, 4.0.1-4.0.4, 5.0.0-5.0.1, 5.1.0, 6.0.0-6.0.1, 6.1.0, 6.2.0-6.2.3, 6.3.0]  
│ │ └─CUDAnative [be33ccc6] log:  
│ │ ├─possible versions are: [0.7.0, 0.8.0-0.8.10, 0.9.0-0.9.1, 0.10.0-0.10.1, 1.0.0-1.0.1, 2.0.0-2.0.1, 2.1.0-2.1.3, 2.2.0-2.2.1, 2.3.0-2.3.1, 2.4.0, 2.5.0-2.5.5, 2.6.0, 2.7.0, 2.8.0-2.8.1, 2.9.0-2.9.1, 2.10.0-2.10.2, 3.0.0-3.0.4, 3.1.0, 3.2.0] or uninstalled  
│ │ ├─restricted to versions \* by an explicit requirement, leaving only versions [0.7.0, 0.8.0-0.8.10, 0.9.0-0.9.1, 0.10.0-0.10.1, 1.0.0-1.0.1, 2.0.0-2.0.1, 2.1.0-2.1.3, 2.2.0-2.2.1, 2.3.0-2.3.1, 2.4.0, 2.5.0-2.5.5, 2.6.0, 2.7.0, 2.8.0-2.8.1, 2.9.0-2.9.1, 2.10.0-2.10.2, 3.0.0-3.0.4, 3.1.0, 3.2.0]  
│ │ ├─restricted by compatibility requirements with Adapt [79e6a3ab] to versions: [0.7.0, 0.8.0-0.8.10, 0.9.0-0.9.1, 2.2.1, 2.3.0-2.3.1, 2.4.0, 2.5.0-2.5.5, 2.6.0, 2.7.0, 2.8.0-2.8.1, 2.9.0-2.9.1, 2.10.0-2.10.2, 3.0.0-3.0.4, 3.1.0, 3.2.0] or uninstalled, leaving only versions: [0.7.0, 0.8.0-0.8.10, 0.9.0-0.9.1, 2.2.1, 2.3.0-2.3.1, 2.4.0, 2.5.0-2.5.5, 2.6.0, 2.7.0, 2.8.0-2.8.1, 2.9.0-2.9.1, 2.10.0-2.10.2, 3.0.0-3.0.4, 3.1.0, 3.2.0]  
│ │ │ └─Adapt [79e6a3ab] log: see above  
│ │ └─restricted by compatibility requirements with CuArrays [3a865a2d] to versions: [3.0.0-3.0.4, 3.1.0, 3.2.0]  
│ │ └─CuArrays [3a865a2d] log: see above  
│ ├─restricted by compatibility requirements with CUDAapi [3895d2a7] to versions: [0.8.2-0.8.6, 0.9.0, 1.0.0-1.0.1, 2.0.0,  
3.0.0-3.0.1, 3.1.0, 4.0.0-4.0.4, 5.0.0-5.0.1, 5.1.0, 6.0.0-6.0.1, 6.1.0, 6.2.0-6.2.3, 6.3.0] or uninstalled, leaving only versions: [0.8.2-0.8.6, 3.0.0-3.0.1, 3.1.0, 4.0.1-4.0.4, 5.0.0-5.0.1, 5.1.0, 6.0.0-6.0.1, 6.1.0, 6.2.0-6.2.3, 6.3.0]  
│ │ └─CUDAapi [3895d2a7] log:  
│ │ ├─possible versions are: [0.5.0-0.5.4, 0.6.0-0.6.3, 1.0.0-1.0.1, 1.1.0, 1.2.0, 2.0.0, 2.1.0, 3.0.0, 3.1.0, 4.0.0] or  
uninstalled  
│ │ ├─restricted to versions \* by an explicit requirement, leaving only versions [0.5.0-0.5.4, 0.6.0-0.6.3, 1.0.0-1.0.1,  
1.1.0, 1.2.0, 2.0.0, 2.1.0, 3.0.0, 3.1.0, 4.0.0]  
│ │ └─restricted by compatibility requirements with CuArrays [3a865a2d] to versions: [3.0.0, 3.1.0, 4.0.0]  
│ │ └─CuArrays [3a865a2d] log: see above  
│ └─restricted by compatibility requirements with CuArrays [3a865a2d] to versions: [6.0.1, 6.1.0, 6.2.0-6.2.3, 6.3.0]  
│ └─CuArrays [3a865a2d] log: see above  
└─restricted by compatibility requirements with CUDA [052768ef] to versions: 2.0.0-2.0.2 — no versions left  
└─CUDA [052768ef] log: see above

---

<div class="post-metadata">

**Author:** ![ChrisRackauckas](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/chrisrackauckas/32/77_2.png) [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)\
**Post date:** [August 25, 2020, 4:15pm UTC](https://discourse.julialang.org/t/diffeqflux-sciml-train-giving-undefvarerror-progresslogging-not-defined/45478/4 "2020-08-25T16:15:20Z")

</div>

> [@matias](#):
>
> Got the same error. when I try to download the lastest version of DiffEqFlux i get this compatibility issue…

That’s because CuArrays was replaced by CUDA.jl

---

<div class="post-metadata">

**Author:** ![junsebas97](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/junsebas97/32/19611_2.png) [@junsebas97](https://discourse.julialang.org/u/junsebas97)\
**Post date:** [November 24, 2020, 3:11pm UTC](https://discourse.julialang.org/t/diffeqflux-sciml-train-giving-undefvarerror-progresslogging-not-defined/45478/5 "2020-11-24T15:11:56Z")

</div>

Hello, I’m using Juno’s debugger in DiffEqFlux.sciml\_train and I get the same error:

> debug\> ERROR: UndefVarError: ProgressLogging not defined  
> Stacktrace:  
> [1] evaluate\_call\_recurse!(::Any, ::JuliaInterpreter.Frame, ::Expr; enter\_generated::Bool) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\interpret.jl:212  
> [2] evaluate\_call\_recurse! at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\interpret.jl:201  
> [inlined]  
> [3] eval\_rhs(::Any, ::JuliaInterpreter.Frame, ::Expr) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\interpret.jl:388  
> [4] step\_expr!(::Any, ::JuliaInterpreter.Frame, ::Any, ::Bool) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\interpret.jl:531  
> [5] step\_expr!(::Any, ::JuliaInterpreter.Frame, ::Bool) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\interpret.jl:581  
> [6] finish!(::Any, ::JuliaInterpreter.Frame, ::Bool) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\commands.jl:14  
> [7] finish\_and\_return! at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\commands.jl:29 [inlined]  
> [8] evaluate\_call\_recurse!(::Any, ::JuliaInterpreter.Frame, ::Expr; enter\_generated::Bool) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\interpret.jl:239  
> … (the last 7 lines are repeated 5 more times)  
> [44] evaluate\_call\_recurse! at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\interpret.jl:201 [inlined]  
> [45] eval\_rhs(::Any, ::JuliaInterpreter.Frame, ::Expr) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\interpret.jl:388  
> [46] step\_expr!(::Any, ::JuliaInterpreter.Frame, ::Any, ::Bool) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\interpret.jl:526  
> [47] step\_expr!(::Any, ::JuliaInterpreter.Frame, ::Bool) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\interpret.jl:581  
> [48] finish!(::Any, ::JuliaInterpreter.Frame, ::Bool) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\commands.jl:14  
> [49] finish\_and\_return!(::Any, ::JuliaInterpreter.Frame, ::Bool) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\commands.jl:29  
> [50] finish\_stack!(::Any, ::JuliaInterpreter.Frame, ::Bool) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\commands.jl:59  
> [51] debug\_command(::Any, ::JuliaInterpreter.Frame, ::Symbol, ::Bool; line::Nothing) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\commands.jl:473  
> [52] debug\_command(::Any, ::JuliaInterpreter.Frame, ::Symbol, ::Bool) at C:\Users\Sebas.julia\packages\JuliaInterpreter\kDn3E\src\commands.jl:415  
> [53] (::Atom.JunoDebugger.var"#54#56"{Bool,Bool,Bool})() at C:\Users\Sebas.julia\packages\Atom\MxsDb\src\debugger\stepper.jl:159  
> [54] evalscope(::Atom.JunoDebugger.var"#54#56"{Bool,Bool,Bool}) at C:\Users\Sebas.julia\packages\Atom\MxsDb\src\debugger\stepper.jl:392  
> [55] startdebugging(::JuliaInterpreter.Frame, ::Bool; istoplevel::Bool, toggle\_ui::Bool) at C:\Users\Sebas.julia\packages\Atom\MxsDb\src\debugger\stepper.jl:157  
> [56] (::Base.var"#inner#2"{Base.Iterators.Pairs{Symbol,Bool,Tuple{Symbol,Symbol},NamedTuple{(:istoplevel, :toggle\_ui),Tuple{Bool,Bool}}},typeof(Atom.JunoDebugger.startdebugging),Tuple{JuliaInterpreter.Frame,Bool}})() at .\essentials.jl:713  
> [57] #invokelatest#1 at .\essentials.jl:714 [inlined]  
> [58] (::Atom.JunoDebugger.var"#48#51"{String,String,Bool,Int64})() at C:\Users\Sebas.julia\packages\Atom\MxsDb\src\debugger\stepper.jl:119  
> [59] hideprompt(::Atom.JunoDebugger.var"#48#51"{String,String,Bool,Int64}) at C:\Users\Sebas.julia\packages\Atom\MxsDb\src\repl.jl:127  
> [60] #47 at C:\Users\Sebas.julia\packages\Atom\MxsDb\src\debugger\stepper.jl:84 [inlined]  
> [61] task\_local\_storage(::Atom.JunoDebugger.var"#47#50"{String,String,Bool,Int64}, ::Symbol, ::String) at .\task.jl:226  
> [62] debug\_file(::String, ::String, ::String, ::Bool, ::Int64) at C:\Users\Sebas.julia\packages\Atom\MxsDb\src\debugger\stepper.jl:83  
> [63] debug\_file(::String, ::String, ::String, ::Bool) at C:\Users\Sebas.julia\packages\Atom\MxsDb\src\debugger\stepper.jl:81  
> [64] handlemsg(::Dict{String,Any}, ::String, ::Vararg{Any,N} where N) at C:\Users\Sebas.julia\packages\Atom\MxsDb\src\comm.jl:169

The version of DiffEqFlux is 1.24.0

Does the debugger have any limitation in DiffEqFlux? Or should it works?

Thanks!!

---

<div class="post-metadata">

**Author:** ![ChrisRackauckas](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/chrisrackauckas/32/77_2.png) [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)\
**Post date:** [November 24, 2020, 6:53pm UTC](https://discourse.julialang.org/t/diffeqflux-sciml-train-giving-undefvarerror-progresslogging-not-defined/45478/6 "2020-11-24T18:53:35Z")

</div>

@pfitzseb is there some weird interaction between the debugger and ProgressLogging?

---

<div class="post-metadata">

**Author:** ![pfitzseb](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/pfitzseb/32/45566_2.png) [@pfitzseb](https://discourse.julialang.org/u/pfitzseb)\
**Post date:** [November 24, 2020, 9:28pm UTC](https://discourse.julialang.org/t/diffeqflux-sciml-train-giving-undefvarerror-progresslogging-not-defined/45478/7 "2020-11-24T21:28:16Z")

</div>

Not as far as I’m aware. Do you have a MWE I can try, @junsebas97?

---

<div class="post-metadata">

**Author:** ![junsebas97](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/junsebas97/32/19611_2.png) [@junsebas97](https://discourse.julialang.org/u/junsebas97)\
**Post date:** [November 25, 2020, 1:31am UTC](https://discourse.julialang.org/t/diffeqflux-sciml-train-giving-undefvarerror-progresslogging-not-defined/45478/8 "2020-11-25T01:31:10Z")

</div>

For example, in the following code:

```

using Flux, DiffEqFlux, DifferentialEquations

# Data: Lotka-Volterra simulation
function lotka_volterra(du, u, p, t)
    x, y = u
    α, β, δ, γ = p
    du[1] = dx = α*x - β*x*y
    du[2] = dy = -δ*y + γ*x*y
end

u0 = [1.0, 1.0] # initial Condition
tspan = (0.0, 15.0) # integration interval
Δt = 0.01
p = [1.5, 1.0, 3.0, 1.0] # system parameters
prob = ODEProblem(lotka_volterra, u0, tspan, p)
sol = solve(prob, Tsit5(), saveat = Δt)
y_real = sol[2, :] # label

# ML model:
ANN = FastChain(FastDense(2, 5, tanh), FastDense(5, 2))
params = initial_params(ANN)
function model(du, u, p, t)
    du[1] = dx = ANN(u, p)[1]
    du[2] = dy = ANN(u, p)[2]
end

function prediction(θ)
    problem = ODEProblem(model, u0, tspan, θ)
    solve(problem, Tsit5(), saveat = Δt)
end

function loss(θ)
    pred = prediction(θ)
    y_pred = pred[2, :]
    sum(abs2, y_real - y_pred)
end
loss(params)

function callback(p, loss_val)
    println(loss_val)
    false
end

sol = DiffEqFlux.sciml_train(loss, params, ADAM(0.05), cb = callback, maxiters = 50)

```

When I put a breakpoint inside the loss function (y\_pred = pred[2, :]) and it’s called by DiffEqFlux.sciml\_train, i get the ProgressLogging error.