# Is there a way to transpose an array of Any? I have a `12×500 Array{Any, 2}` I want

Is there a way to transpose an array of Any? I have a `12×500 Array{Any,2}` I want it to be 500x12. If I do transpose it throws an error.

``````500×12 LinearAlgebra.Transpose{Any,Array{Any,2}}:
Error showing value of type LinearAlgebra.Transpose{Any,Array{Any,2}}:
ERROR: MethodError: no method matching transpose(::String)
Closest candidates are:
transpose(::Missing) at missing.jl:100
transpose(::Number) at number.jl:168
``````

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(Original message ) (More Info)

In Julia, transpose is firmly rooted in linear algebra, but `permutedims` allows swapping of dimensions of any type of object. In other words,

``````julia> A = Any["hello" for i = 1:3, j=1:2]
3×2 Matrix{Any}:
"hello"  "hello"
"hello"  "hello"
"hello"  "hello"

julia> permutedims(A, (2, 1))
2×3 Matrix{Any}:
"hello"  "hello"  "hello"
"hello"  "hello"  "hello"

julia> transpose(A)
2×3 transpose(::Matrix{Any}) with eltype Any:
Error showing value of type Transpose{Any, Matrix{Any}}:
ERROR: MethodError: no method matching transpose(::String)
...
``````

Why the distinction? Well, notice that the error message is telling you it’s trying to take `transpose(::String)`, which isn’t a defined operation. Why does it take the transpose of elements? It’s useful/necessary for generic linear algebra, as one can see with this vector-of-vectors:

``````julia> x = [[1,2], [10,11]]
2-element Vector{Vector{Int64}}:
[1, 2]
[10, 11]

julia> x'*x
226

julia> x'*x + x'*x
226
``````

So not only does it reshape the container `x`, it also reshapes each element.

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For anyone looking to get involved in Julia development, here’s an issue to get your feet wet: Add hint for MethodError on transpose/adjoint · Issue #39938 · JuliaLang/julia · GitHub

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