# Optimizer not found error
**URL:** https://discourse.julialang.org/t/optimizer-not-found-error/92364
**Category:** General Usage
**Created:** [December 31, 2022, 5:14pm UTC](https://discourse.julialang.org/t/optimizer-not-found-error/92364 "2022-12-31T17:14:41Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@erlebach](https://discourse.julialang.org/u/erlebach)
#### Post date: [December 31, 2022, 5:14pm UTC](https://discourse.julialang.org/t/optimizer-not-found-error/92364/1 "2022-12-31T17:14:41Z")
@ChrisRackauckas,
I am running a UODE solver using `Optimization.jl` per recommendation.
Here are a few lines from a larger code (I might construct a MWE later).
```julia
adtype = Optimization.AutoZygote()
# adtype = Optimization.AutoFiniteDiff()
# ERROR: Cannot find function signature. Must wait on Rackauckas
optf = Optimization.OptimizationFunction((x,p)->loss_neuralode(x), adtype)
# Componentarray is a projection operator
optprob = Optimization.OptimizationProblem(optf, ComponentVector{Float64}(ps_NN))
res1 = Optimization.solve(optprob, Adam(0.1), maxiters=200)
```
I get the error:
```julia
Chosen Optimizer: Adam{Float64}(0.1, (0.8999999761581421, 0.9990000128746033), 2.220446049250313e-16)
Stacktrace:
[1] __solve(::OptimizationProblem{true, OptimizationFunction{true, Optimization.AutoZygote, var"#24#25", Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, typeof(SciMLBase.DEFAULT_OBSERVED_NO_TIME), Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing}, ComponentVector{Float64, Vector{Float64}, Tuple{Axis{(coeffs = ViewAxis(1:20, ShapedAxis((10, 2), NamedTuple())),)}}}, SciMLBase.NullParameters, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Base.Pairs{Symbol, Union{}, Tuple{}, NamedTuple{(), Tuple{}}}}, ::Adam{Float64}; kwargs::Base.Pairs{Symbol, Int64, Tuple{Symbol}, NamedTuple{(:maxiters,), Tuple{Int64}}})
@ SciMLBase ~/.julia/packages/SciMLBase/QqtZA/src/solve.jl:177
[2] solve(::OptimizationProblem{true, OptimizationFunction{true, Optimization.AutoZygote, var"#24#25", Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, typeof(SciMLBase.DEFAULT_OBSERVED_NO_TIME), Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing}, ComponentVector{Float64, Vector{Float64}, Tuple{Axis{(coeffs = ViewAxis(1:20, ShapedAxis((10, 2), NamedTuple())),)}}}, SciMLBase.NullParameters, Nothing, Nothing, Nothing, Nothing, Nothing, Nothing, Base.Pairs{Symbol, Union{}, Tuple{}, NamedTuple{(), Tuple{}}}}, ::Adam{Float64}; kwargs::Base.Pairs{Symbol, Int64, Tuple{Symbol}, NamedTuple{(:maxiters,), Tuple{Int64}}})
@ SciMLBase ~/.julia/packages/SciMLBase/QqtZA/src/solve.jl:88
[3] top-level scope
@ ~/src/2022/basic_UODE/custom_lux_layer/Lokta-Voltera_polylayer.jl:160
Adam{Float64}(0.1, (0.8999999761581421, 0.9990000128746033), 2.220446049250313e-16)
```
I looked at the Julia source code and found that the `solve` function in `SciMLBase.jl` is called:
```julia
# if no cache interface is supported at least the following method has to be defined
function __solve(prob::OptimizationProblem, alg, args...; kwargs...)
throw(OptimizerMissingError(alg))
end
```
Why is it that the `Adam` algorithm is not recognized? While waiting for a response, I’ll work on a MWE. Thanks.
---
### Author:  [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)
#### Post date: [December 31, 2022, 6:01pm UTC](https://discourse.julialang.org/t/optimizer-not-found-error/92364/2 "2022-12-31T18:01:34Z")
Did you `using OptimizationOptimisers`?
---
### Author:  [@erlebach](https://discourse.julialang.org/u/erlebach)
#### Post date: [December 31, 2022, 6:24pm UTC](https://discourse.julialang.org/t/optimizer-not-found-error/92364/3 "2022-12-31T18:24:03Z")
No, I used `Optimisers` on its own. Is that not correct?
I checked out `OptimizationOptimisers` and looked at its various functions. I notice that `ADAM`, which is deprecated is still in this package. Why? I also notice that `freeze!` is not in the package, although it is in `Optimisers.jl`. So my question is: when does one use `OptimizsationOptimisers.jl` as opposed to `Optimisers.jl`. Thanks.
In fact, a google search of “OptimizationOptimisers.jl”" does not return any results. Not clear how that is possible. 🙂
---
### Author:  [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)
#### Post date: [December 31, 2022, 6:40pm UTC](https://discourse.julialang.org/t/optimizer-not-found-error/92364/5 "2022-12-31T18:40:45Z")
> [@erlebach](#):
>
> I notice that `ADAM`, which is deprecated is still in this package. Why?
`ADAM` is different from `Adam`. Flux has `ADAM`, and Optimisers has `Adam`.
> [@erlebach](#):
>
> No, I used `Optimisers` on its own. Is that not correct?
To use any of the optimization packages with Optimization.jl, you need to load the wrapper. See the documentation page:
> **[Optimisers.jl · Optimization.jl](https://docs.sciml.ai/Optimization/stable/optimization_packages/optimisers/)**
>
> Documentation for Optimization.jl.
It’s a bit unfortunate, though with Julia v1.9 we can make use of the new weak dependencies feature to make that easier.
---
### Author:  [@erlebach](https://discourse.julialang.org/u/erlebach)
#### Post date: [December 31, 2022, 6:45pm UTC](https://discourse.julialang.org/t/optimizer-not-found-error/92364/6 "2022-12-31T18:45:13Z")
Thanks. Note that the demo you shared with me a while back, did not require this wrapper. Why is it that `Optimisers.jl` does not simply include `OptimizationOptimisers.jl` as a package. Is that not possible? Thanks.
---
### Author:  [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)
#### Post date: [December 31, 2022, 6:47pm UTC](https://discourse.julialang.org/t/optimizer-not-found-error/92364/7 "2022-12-31T18:47:33Z")
> [@erlebach](#):
>
> Why is it that `Optimisers.jl` does not simply include `OptimizationOptimisers.jl` as a package. Is that not possible?
It’s not possible until Julia v1.9.
> [@erlebach](#):
>
> Note that the demo you shared with me a while back, did not require this wrapper
Which demo?
---
### Author:  [@erlebach](https://discourse.julialang.org/u/erlebach)
#### Post date: [December 31, 2022, 6:51pm UTC](https://discourse.julialang.org/t/optimizer-not-found-error/92364/8 "2022-12-31T18:51:04Z")
A few weeks ago, when you were updating the documentation, you shared a demo program using the latest libraries that demonstrated the L-V equation with `Lux` and `DataDrivenEq`, and helped me get the code running. I just looked, and `OptimizationOptimiers` is indeed loaded (I had forgotten).
Here is the “demo”: [Automatically Discover Missing Physics by Embedding Machine Learning into Differential Equations · Overview of Julia's SciML](https://docs.sciml.ai/Overview/dev/showcase/missing_physics/)
Just one question: If I load `OptimizatonOptimisers`, is `Optimisers` also necessary? Many functions are contained in both libraries but not all. Why were all the functions in `Optimisers.jl` transferred over? I am probably digging into the weeds too much 🙂
```
Gordon
```
---
### Author:  [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)
#### Post date: [December 31, 2022, 7:07pm UTC](https://discourse.julialang.org/t/optimizer-not-found-error/92364/9 "2022-12-31T19:07:03Z")
> [@erlebach](#):
>
> Just one question: If I load `OptimizatonOptimisers`, is `Optimisers` also necessary? Many functions are contained in both libraries but not all. Why were all the functions in `Optimisers.jl` transferred over?
Optimisers.jl is a separate library we don’t control. OptimizationOptimisers wraps it into the Optimization.jl API. It would be nice if libraries adopted the Optimization.jl API themselves, that would get rid of the wrapper, but the API is still young enough that it’s not surprising and with the weak dependencies stuff we can make that automatic.
---
### Author:  [@erlebach](https://discourse.julialang.org/u/erlebach)
#### Post date: [December 31, 2022, 7:08pm UTC](https://discourse.julialang.org/t/optimizer-not-found-error/92364/10 "2022-12-31T19:08:09Z")
Thanks. This makes sense. Cheers!