# Error running model-zoo example cifar10.jl of the Flux package
**URL:** https://discourse.julialang.org/t/error-running-model-zoo-example-cifar10-jl-of-the-flux-package/19991
**Category:** General Usage
**Tags:** flux
**Created:** [January 23, 2019, 3:59pm UTC](https://discourse.julialang.org/t/error-running-model-zoo-example-cifar10-jl-of-the-flux-package/19991 "2019-01-23T15:59:57Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@arnaudmgh](https://discourse.julialang.org/u/arnaudmgh)
#### Post date: [January 23, 2019, 3:59pm UTC](https://discourse.julialang.org/t/error-running-model-zoo-example-cifar10-jl-of-the-flux-package/19991/1 "2019-01-23T15:59:57Z")
I tried with `]instantiate` first, and without, same result. Seems to be a problem with conversion to Float32 of Forward.Diff.Dual. Not sure how to go about it, any help would be appreciated.
```julia
julia> include("cifar10.jl")
ERROR: LoadError: MethodError: no method matching Float32(::ForwardDiff.Dual{Nothing,Float64,1})
Closest candidates are:
Float32(::Real, ::RoundingMode) where T<:AbstractFloat at rounding.jl:185
Float32(::T<:Number) where T<:Number at boot.jl:725
Float32(::Int8) at float.jl:60
...
in expression starting at /Users/aamzallag/code_programming/julia/model-zoo/vision/cifar10/cifar10.jl:122
```
---
### Author:  [@kristoffer.carlsson](https://discourse.julialang.org/u/kristoffer.carlsson)
#### Post date: [January 23, 2019, 4:08pm UTC](https://discourse.julialang.org/t/error-running-model-zoo-example-cifar10-jl-of-the-flux-package/19991/2 "2019-01-23T16:08:28Z")
Maybe fixed by [conversions for dual numbers · FluxML/Flux.jl@152ce4a · GitHub](https://github.com/FluxML/Flux.jl/commit/152ce4a164a4602bf8804090e79b1ca59772f70c).
Try use Flux master?
---
### Author:  [@arnaudmgh](https://discourse.julialang.org/u/arnaudmgh)
#### Post date: [January 23, 2019, 4:17pm UTC](https://discourse.julialang.org/t/error-running-model-zoo-example-cifar10-jl-of-the-flux-package/19991/3 "2019-01-23T16:17:09Z")
Thank you! I am trying that (cifar10.jl takes a few minutes to run).
Quick question: I did `]add Flux#master` (activated project is `cifar10`). Is it the right way to do it? Does it modifies the Manifest.toml so that it will always use this git commit?
---
### Author:  [@arnaudmgh](https://discourse.julialang.org/u/arnaudmgh)
#### Post date: [January 23, 2019, 4:34pm UTC](https://discourse.julialang.org/t/error-running-model-zoo-example-cifar10-jl-of-the-flux-package/19991/4 "2019-01-23T16:34:51Z")
Unfortunately that did not work:
```julia
(cifar10) pkg> add Flux#master
Cloning git-repo `https://github.com/FluxML/Flux.jl.git`
Updating git-repo `https://github.com/FluxML/Flux.jl.git`
Resolving package versions...
Updating `~/code_programming/julia/model-zoo/vision/cifar10/Project.toml`
[587475ba] ↑ Flux v0.7.1 ⇒ v0.7.1+ #master (https://github.com/FluxML/Flux.jl.git)
Updating `~/code_programming/julia/model-zoo/vision/cifar10/Manifest.toml`
[587475ba] ↑ Flux v0.7.1 ⇒ v0.7.1+ #master (https://github.com/FluxML/Flux.jl.git)
julia> include("cifar10.jl")
ERROR: LoadError: MethodError: no method matching Float32(::ForwardDiff.Dual{Nothing,Float64,1})
Closest candidates are:
Float32(::Real, ::RoundingMode) where T<:AbstractFloat at rounding.jl:185
Float32(::T<:Number) where T<:Number at boot.jl:725
Float32(::Int8) at float.jl:60
...
in expression starting at /Users/aamzallag/code_programming/julia/model-zoo/vision/cifar10/cifar10.jl:122
```
line 122 where is fails is:
```julia
Flux.train!(loss, params(m), train, opt, cb = evalcb)
```
I don’t know how to go from there, to find where in the function calls the error happens…