I have data (originally pulled in from python via pycall) that is naturally stored in a 2D array (N, 3) (i…e, it is an array of points in 3D). Right now, I can wrap this in Julia with the command: X = unsafe_wrap(Array{Float64,2}, Ptr{Float64}(Xptr), (3,N)) What I would like to do is have this wr…

You could reinterpret the data as a vector of SVectors from StaticArrays: using StaticArrays julia> x = [1 2 3; 4 5 6] 2×3 Array{Int64,2}: 1 2 3 4 5 6 julia> reinterpret(SVector{2, Int}, x, (size(x, 2),)) 3-element Array{SVector{2,Int64},1}: [1, 4] [2, 5] [3, 6] Alternatively, you could …

Does reinterpreting copy the data, or just change the indexing mechanism? I want the latter.

It just creates a new interpretation of the same data.

Note that on 0.7 this will create a ReinterpretedArray which unfortunately has overhead in some cases: https://github.com/JuliaLang/julia/issues/25014

[image] gideonsimpson: X = unsafe_wrap(Array{Float64,2}, Ptr{Float64}(Xptr), (3,N)) What about just doing this? using StaticArrays X = unsafe_wrap(Array{SVector{3,Float64},1}, Ptr{SVector{3,Float64}}(Xptr), (N,))

No, the memory was allocated by python and will be freed by python. gideonsimpson needs to deal with this problem anyway. Or did I misunderstand the context?

I missed the whole pycall thing…

Unsafe_wrap with array of arrays

General Usage

kristoffer.carlsson January 3, 2018, 8:58pm 7

But that has the same problem as described in ANN: InplaceRealFFT.jl : inplace real-to-complex and complex-to-real FFT - #9 by yuyichao?

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Unsafe_wrap with array of arrays

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