# How to use LAPACK and BLAS for Julia 1.6.1 in UBUNTU 20.04

**URL:** <https://discourse.julialang.org/t/how-to-use-lapack-and-blas-for-julia-1-6-1-in-ubuntu-20-04/65396>\
**Category:** New to Julia\
**Tags:** question, package\
**Created:** [July 27, 2021, 6:07pm UTC](https://discourse.julialang.org/t/how-to-use-lapack-and-blas-for-julia-1-6-1-in-ubuntu-20-04/65396 "2021-07-27T18:07:57Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Aniruddha](https://avatars.discourse-cdn.com/v4/letter/a/839c29/32.png) [@Aniruddha](https://discourse.julialang.org/u/Aniruddha)\
**Post date:** [July 27, 2021, 6:07pm UTC](https://discourse.julialang.org/t/how-to-use-lapack-and-blas-for-julia-1-6-1-in-ubuntu-20-04/65396/1 "2021-07-27T18:07:57Z")

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I am getting the following error while trying to run the Extrusion function in the Gmsh package through Julia API:  
**Error : LU factorization and substitution requires LAPACK**

I think in my system, Julia cannot initiate the LAPACK package (also BLAS) on its own, or else, LAPACK and BLAS are not there at all in the system. Please help in this regard.

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**Author:** ![stevengj](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/stevengj/32/71_2.png) [@stevengj](https://discourse.julialang.org/u/stevengj)\
**Post date:** [July 27, 2021, 9:54pm UTC](https://discourse.julialang.org/t/how-to-use-lapack-and-blas-for-julia-1-6-1-in-ubuntu-20-04/65396/3 "2021-07-27T21:54:48Z")

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> [@Aniruddha](#):
>
> I am getting the following error while trying to run the Extrusion function in the Gmsh package through Julia API:  
> **Error : LU factorization and substitution requires LAPACK**

It sounds like the `gmsh` library/binary being installed by `Gmsh.jl` is not linked with LAPACK. (This error is coming from `gmsh`, not from Julia — Julia itself is always linked with LAPACK.)