# Sample() nchains vs n\_chains

**URL:** <https://discourse.julialang.org/t/sample-nchains-vs-n-chains/50336>\
**Category:** General Usage\
**Tags:** question, turing\
**Created:** [November 17, 2020, 10:14pm UTC](https://discourse.julialang.org/t/sample-nchains-vs-n-chains/50336 "2020-11-17T22:14:00Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![jzr](https://avatars.discourse-cdn.com/v4/letter/j/eb9ed0/32.png) [@jzr](https://discourse.julialang.org/u/jzr)\
**Post date:** [November 17, 2020, 10:14pm UTC](https://discourse.julialang.org/t/sample-nchains-vs-n-chains/50336/1 "2020-11-17T22:14:00Z")

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`sample()` has many methods. One has `nchains` and another has `n_chains`. What is the difference between these parameters?

```julia
nchains: sample(model::AbstractMCMC.AbstractModel, sampler::AbstractMCMC.AbstractSampler, parallel::AbstractMCMC.AbstractMCMCParallel, N::Integer, nchains::Integer; kwargs...) in AbstractMCMC
n_chains: sample(rng::AbstractRNG, model::AbstractMCMC.AbstractModel, sampler::DynamicPPL.Sampler{var"#s60",S} where S<:DynamicPPL.AbstractSamplerState where var"#s60"<:Turing.Inference.InferenceAlgorithm, parallel::AbstractMCMC.AbstractMCMCParallel, N::Integer, n_chains::Integer; chain_type, progress, kwargs...) in Turing.Inference

```

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**Author:** ![trappmartin](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/trappmartin/32/1165_2.png) [@trappmartin](https://discourse.julialang.org/u/trappmartin)\
**Post date:** [November 18, 2020, 7:51pm UTC](https://discourse.julialang.org/t/sample-nchains-vs-n-chains/50336/2 "2020-11-18T19:51:34Z")

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cc: @cpfiffer

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**Author:** ![cpfiffer](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/cpfiffer/32/208747_2.png) [@cpfiffer](https://discourse.julialang.org/u/cpfiffer)\
**Post date:** [November 19, 2020, 3:16am UTC](https://discourse.julialang.org/t/sample-nchains-vs-n-chains/50336/3 "2020-11-19T03:16:46Z")

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The first one is the method that you end up calling – the second is an internal one that eventually gets called by the first. Practically, it doesn’t matter much that it’s `n_chains` vs. `nchains`, since the first method call is positional and not a keyword argument.

That said, these should probably be unified just to avoid confusion.