Request: Add CSR, LiL, DOK, COO sparse matrix data structures, to allow more users to migrate from Python scipy.sparse?

[lampretl]

Hello, developers of SparseArrays.jl.

Is it planned that you will some day add CSR, LiL, DOK, COO sparse matrix data structures to your library?

If not, I respectfully suggest you go in this direction, since Python's scipy.sparse library already has that supported, but does have other drawbacks, e.g. it does not allow rationals (exact fractions) as matrix entries (not without performance deterioration).

Having those formats included would make it much easier to switch from Python to Julia. Standard operations on those matrices are much desired, like selecting/permuting rows/cols, multiplicating rows/cols by an array of scalars, and multiplication of 2 matrices.