Is there an elegant/optimized way to take the outer product of 3 sparse vectors? Problem 1: Triple Outer Product In numpy I can just chain calls to np.outer(np.outer(v,v),v) but I cannot do the same in Julia. I see this example but that’s a bit gross and does not take advantage of the sparsity wh…

Guess I should mark a solution: This can be done using SparseArrayKit.jl and TensorOperations.jl via: N = 10 u = SparseArray{Float64}(undef,(N,)) @tensor sparse_triple_outer_product[i,j,k] := u[i] * u[j] * u[k]

Yeah basically just arbitrary dimension sparse arrays (4th is the most I’d need). There are a decent amount of threads asking for this functionality, is there any reason this could not or should not be added to SparseArrays in the Julia Base? Like you mention there are a few packages out there, but…

[image] ejmeitz: There are a decent amount of threads asking for this functionality, is there any reason this could not or should not be added to SparseArrays in the Julia Base? Multidimensional sparse arrays are best stored in totally different data structures than sparse matrices and vector…

Oh nothing seems wrong. This is more my personal aspirations for packages in Julia. I know Julia is still relatively new, but one day I would like to see a lot of these smaller packages wrapped into consistently maintained and documented packages instead of having the sprawl of undocumented and dea…

Outer Product of SparseMatrix and SparseVector

General Usage

stevengj April 26, 2023, 1:54pm 2

Do you want a 3d sparse array as the result? The SparseArrays package does not support this, but there are other packages that do: Sparse 3D arrays - #7 by jovansam

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Outer Product of SparseMatrix and SparseVector

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