How to do sparse row vector*matrix?

New to Julia
1

I am trying to do a row vector times a matrix but it give an adjoint type instead of a row vector? should I do (A’A[1,:])'? I need the results to be a vector so I can continue other calculation.
Thanks.

A=sparse([1 2;3 4])
A[1,:]'A

#1×2 adjoint(::SparseVector{Int64, Int64}) with eltype Int64

2

That is a row vector. https://www.youtube.com/watch?v=C2RO34b_oPM

3

Thanks. But I just did a type conversion for it like:
sparsevec(A[1,:]'A)

This solved my problem.

4

A little more direct (and performant) is either of

julia> (A[1,:]' * A)'
2-element SparseVector{Int64, Int64} with 2 stored entries:
  [1]  =  7
  [2]  =  10

julia> A' * A[1,:]
2-element SparseVector{Int64, Int64} with 2 stored entries:
  [1]  =  7
  [2]  =  10

For real numbers this is fine, but if your numbers are complex then you should be careful about the conjugation of the result.