# What are IFFxM methods is StochasticDiffEq.jl?

**URL:** https://discourse.julialang.org/t/what-are-iffxm-methods-is-stochasticdiffeq-jl/111899
**Category:** Numerics
**Tags:** question, diffeq, sde
**Created:** [March 20, 2024, 6:33pm UTC](https://discourse.julialang.org/t/what-are-iffxm-methods-is-stochasticdiffeq-jl/111899 "2024-03-20T18:33:42Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![homocomputeris](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/homocomputeris/32/8933_2.png) [@homocomputeris](https://discourse.julialang.org/u/homocomputeris)
#### Post date: [March 20, 2024, 6:33pm UTC](https://discourse.julialang.org/t/what-are-iffxm-methods-is-stochasticdiffeq-jl/111899/1 "2024-03-20T18:33:42Z")

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What are these methods in StochasticDiffEq.jl and in which papers are they described?

> <https://github.com/SciML/StochasticDiffEq.jl/blob/5fb37216efd759df26df89a00e6992a0e440b4d9/src/alg_utils.jl#L56C1-L58C33>

They are declared and implemented, but they seem to be [undocumented](https://docs.sciml.ai/DiffEqDocs/stable/solvers/sde_solve/). Or have a different name.

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### 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: [March 27, 2024, 9:12am UTC](https://discourse.julialang.org/t/what-are-iffxm-methods-is-stochasticdiffeq-jl/111899/2 "2024-03-27T09:12:34Z")

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> **[An Integration Factor Method for Stochastic and Stiff Reaction-Diffusion Systems](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4430728/)**
>
> Stochastic effects are often present in the biochemical systems involving reactions and diffusions. When the reactions are stiff, existing numerical methods for stochastic reaction diffusion equations require either very small time steps for any...

It’s undocumented because improving them is still a research topic.