# Alternatives to inv() in Julia

**URL:** <https://discourse.julialang.org/t/alternatives-to-inv-in-julia/116514>\
**Category:** Numerics\
**Tags:** question, performance\
**Created:** [July 2, 2024, 10:37am UTC](https://discourse.julialang.org/t/alternatives-to-inv-in-julia/116514 "2024-07-02T10:37:47Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![usaer](https://avatars.discourse-cdn.com/v4/letter/u/b9bd4f/32.png) [@usaer](https://discourse.julialang.org/u/usaer)\
**Post date:** [July 2, 2024, 10:37am UTC](https://discourse.julialang.org/t/alternatives-to-inv-in-julia/116514/1 "2024-07-02T10:37:47Z")

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Hi, I wanted to ask if there more optimal way w.r.t to Performance to find the inverse of a matrix than inv() from Linear Algebra package

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**Author:** ![JM\_Beckers](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/jm_beckers/32/22482_2.png) [@JM\_Beckers](https://discourse.julialang.org/u/JM_Beckers)\
**Post date:** [July 2, 2024, 11:25am UTC](https://discourse.julialang.org/t/alternatives-to-inv-in-julia/116514/2 "2024-07-02T11:25:05Z")

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You might have a look at the discussion here:

> [@Why re-use factorization(A) rather than inv(A)](https://discourse.julialang.org/t/why-re-use-factorization-a-rather-than-inv-a/113234):
>
> What is the advantage of first decomposing and then left dividing every time over inverting once and multiplying the inverse every time?

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**Author:** ![mkitti](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mkitti/32/12459_2.png) [@mkitti](https://discourse.julialang.org/u/mkitti)\
**Post date:** [July 2, 2024, 2:54pm UTC](https://discourse.julialang.org/t/alternatives-to-inv-in-julia/116514/3 "2024-07-02T14:54:23Z")

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The first question is why do you need the inverse to begin with?

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**Author:** ![usaer](https://avatars.discourse-cdn.com/v4/letter/u/b9bd4f/32.png) [@usaer](https://discourse.julialang.org/u/usaer)\
**Post date:** [July 3, 2024, 8:53am UTC](https://discourse.julialang.org/t/alternatives-to-inv-in-julia/116514/5 "2024-07-03T08:53:14Z")

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> [@usaer](#):
>
> Just was calculating transformation matrices for which i had to invert the system to solve

Just was calculating transformation matrices for which i had to invert the system to solve

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**Author:** ![mkitti](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mkitti/32/12459_2.png) [@mkitti](https://discourse.julialang.org/u/mkitti)\
**Post date:** [July 3, 2024, 9:08am UTC](https://discourse.julialang.org/t/alternatives-to-inv-in-julia/116514/6 "2024-07-03T09:08:06Z")

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Could you just do matrix division instead of calculating the inverse? That would be usually preferred and more stable.