# \#row-major

**URL:** https://discourse.julialang.org/tag/row-major/606.md

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## [Checking strided array storage order](https://discourse.julialang.org/t/checking-strided-array-storage-order/128685)

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**Author:** [@stemann](https://discourse.julialang.org/u/stemann)\
**Replies:** 1\
**Last updated:** [May 4, 2025, 11:18am UTC](https://discourse.julialang.org/t/checking-strided-array-storage-order/128685 "2025-05-04T11:18:08Z")

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Is strides(array) == Base.size\_to\_strides(1, size(array)...) a sane way to check if a strided array is in column-major (alias co-lexicographic, alias Fortran, alias Julia) order, storage-wise? Cf. julia/base/abstracta…

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## [What are the pros and cons of row/column major ordering?](https://discourse.julialang.org/t/what-are-the-pros-and-cons-of-row-column-major-ordering/110045)

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**Author:** [@leespen1](https://discourse.julialang.org/u/leespen1)\
**Replies:** 10\
**Last updated:** [February 13, 2024, 4:53pm UTC](https://discourse.julialang.org/t/what-are-the-pros-and-cons-of-row-column-major-ordering/110045 "2024-02-13T16:53:10Z")

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I understand that because matrices in Julia are stored in column major order, it is best to iterate over them in column major order. What is less clear to me is why one would want to store matrices in column major order…

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## [Optimal column to row major conversion](https://discourse.julialang.org/t/optimal-column-to-row-major-conversion/99989)

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**Author:** [@xgdgsc](https://discourse.julialang.org/u/xgdgsc)\
**Replies:** 7\
**Last updated:** [June 7, 2023, 11:10pm UTC](https://discourse.julialang.org/t/optimal-column-to-row-major-conversion/99989 "2023-06-07T23:10:56Z")

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When converting column major to row major array. When the array dimension become large. It can be tricky to implement fast conversion. Tricks like ENH: Improve performance for copying/relayout of large data · Issue #2165…

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## [Row and column major order for arrays of different shape](https://discourse.julialang.org/t/row-and-column-major-order-for-arrays-of-different-shape/79297)

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**Author:** [@fedoroff](https://discourse.julialang.org/u/fedoroff)\
**Replies:** 23\
**Last updated:** [April 12, 2022, 1:05pm UTC](https://discourse.julialang.org/t/row-and-column-major-order-for-arrays-of-different-shape/79297 "2022-04-12T13:05:12Z")

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In the following code the functions r\_major and c\_major iterate over array a in the row and column major order: using BenchmarkTools function r\_major!(a) N1, N2 = size(a) for i=1:N1 for j=1:N2 a\[i,j…

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## [Why is \`copy(adjoint)\` not an adjoint object?](https://discourse.julialang.org/t/why-is-copy-adjoint-not-an-adjoint-object/55371)

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**Author:** [@Krastanov](https://discourse.julialang.org/u/Krastanov)\
**Replies:** 12\
**Last updated:** [February 18, 2021, 7:03am UTC](https://discourse.julialang.org/t/why-is-copy-adjoint-not-an-adjoint-object/55371 "2021-02-18T07:03:11Z")

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This surprised me: julia\> typeof(copy(rand(4,4)')) Matrix{Float64} (alias for Array{Float64, 2}) julia\> typeof(deepcopy(rand(4,4)')) LinearAlgebra.Adjoint{Float64, Matrix{Float64}} I have an algorithm which looks pret…