# Error saving MCMC Chain

**URL:** <https://discourse.julialang.org/t/error-saving-mcmc-chain/98225>\
**Category:** Performance\
**Created:** [May 3, 2023, 1:04am UTC](https://discourse.julialang.org/t/error-saving-mcmc-chain/98225 "2023-05-03T01:04:03Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![ALIAN\_LI\_MARTIN](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/alian_li_martin/32/38653_2.png) [@ALIAN\_LI\_MARTIN](https://discourse.julialang.org/u/ALIAN_LI_MARTIN)\
**Post date:** [May 3, 2023, 1:04am UTC](https://discourse.julialang.org/t/error-saving-mcmc-chain/98225/1 "2023-05-03T01:04:03Z")

</div>

Hello, I have an error when saving the MCMC strings. Could someone help me with this problem. Thank you so much.

```julia
MethodError: no method matching write(::IOStream, ::Chains{Float64, AxisArrays.AxisArray{Float64, 3, Array{Float64, 3}, Tuple{AxisArrays.Axis{:iter, StepRange{Int64, Int64}}, AxisArrays.Axis{:var, Vector{Symbol}}, AxisArrays.Axis{:chain, UnitRange{Int64}}}}, Missing, NamedTuple{(:parameters, :internals), Tuple{Vector{Symbol}, Vector{Symbol}}}, NamedTuple{(:start_time, :stop_time), Tuple{Vector{Float64}, Vector{Float64}}}})
Closest candidates are:
  write(::IO, ::Any) at io.jl:672
  write(::IO, ::Any, ::Any...) at io.jl:673
  write(::FilePathsBase.AbstractPath, ::Any) at C:\Users\alian\.julia\packages\FilePathsBase\9kSEl\src\path.jl:771

```