# How to make division for SparceMatrices?

**URL:** <https://discourse.julialang.org/t/how-to-make-division-for-sparcematrices/70006>\
**Category:** General Usage\
**Tags:** question\
**Created:** [October 18, 2021, 9:30pm UTC](https://discourse.julialang.org/t/how-to-make-division-for-sparcematrices/70006 "2021-10-18T21:30:58Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Amro](https://avatars.discourse-cdn.com/v4/letter/a/4491bb/32.png) [@Amro](https://discourse.julialang.org/u/Amro)\
**Post date:** [October 18, 2021, 9:30pm UTC](https://discourse.julialang.org/t/how-to-make-division-for-sparcematrices/70006/1 "2021-10-18T21:30:58Z")

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In my below MWE, I am trying to use `\` for two Sparce matrices, but I am having an error. Any way to solve it?

```julia
using SparseArrays;
using LinearAlgebra;
using .Threads
using BenchmarkTools
using StaticArrays
A = [1 3 3; 6 9 7;-3 3 4]; As = sparse([1 3 3; 6 9 7;-3 3 4]); b = [1,2,3]; bs = sparse([1,2,3]);
E = As \ bs;

ERROR: LoadError: MethodError: no method matching ldiv!(::SuiteSparse.UMFPACK.UmfpackLU{Float64, Int64}, ::SparseVector{Float64, Int64})
Closest candidates are:
  ldiv!(::LU{T, Tridiagonal{T, V}}, ::AbstractVecOrMat{T} where T) where {T, V} at C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\LinearAlgebra\src\lu.jl:583
  ldiv!(::UpperHessenberg, ::AbstractVecOrMat{T} where T; shift) at C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\LinearAlgebra\src\hessenberg.jl:127    
  ldiv!(::LDLt{var"#s832", var"#s831"} where {var"#s832", var"#s831"<:SymTridiagonal}, ::AbstractVecOrMat{T} where T) at C:\buildbot\worker\package_win64\build\usr\share\julia\stdlib\v1.6\LinearAlgebra\src\ldlt.jl:169
  ...
Stacktrace:

```

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<div class="post-metadata">

**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:** [October 18, 2021, 9:36pm UTC](https://discourse.julialang.org/t/how-to-make-division-for-sparcematrices/70006/2 "2021-10-18T21:36:20Z")

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Only the matrix should be sparse, not the vector.

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<div class="post-metadata">

**Author:** ![Amro](https://avatars.discourse-cdn.com/v4/letter/a/4491bb/32.png) [@Amro](https://discourse.julialang.org/u/Amro)\
**Post date:** [October 18, 2021, 9:43pm UTC](https://discourse.julialang.org/t/how-to-make-division-for-sparcematrices/70006/3 "2021-10-18T21:43:03Z")

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Is there any reason for that?

Is there any trick to change the vector `b` to matrix of single dimension?