I have defined two structs in Julia: RankOneMatrix and FirstRankOneMatrix.

struct RankOneMatrix{T} <: AbstractMatrix{T}
    v::AbstractVector{T}
    w::AbstractVector{T}
end

RankOneMatrix(v) = RankOneMatrix(v, v)

struct FirstRankOneMatrix
    v::Vector{Float64}
    w::Vector{Float64}
end

FirstRankOneMatrix(v) = FirstRankOneMatrix(v, v)

When I initialize FirstRankOneMatrix with a vector, it outputs the values stored in a 1-D array as expected. However, when I initialize RankOneMatrix, it outputs a 2-D array of the outer products.

I’m new to Julia and I’m struggling to understand this behavior. Could this be related to the fact that RankOneMatrix is a subtype of AbstractMatrix? Any insights would be appreciated.