mwe.jl

module mwe
using RecursiveArrayTools

abstract type AbstractTransientSolution{T,N,A,B}  <: AbstractDiffEqArray{T, N, A} end

mutable struct TransientSolution{T,N,A,B} <: AbstractTransientSolution{T,N,A,B}
    u::A
    t::B
end

TransientSolution(vec::AbstractVector{T}, ts, ::NTuple{N}) where {T, N} = TransientSolution{eltype(T), N, typeof(vec), typeof(ts)}(vec, ts)

TransientSolution(vec::AbstractVector,ts::AbstractVector) = TransientSolution(vec, ts, (size(vec[1])..., length(vec)))

Base.append!(s::TransientSolution,t::Real,sol::AbstractArray)=push!(s.t,t), push!(s.u,copy(sol))

function TransientSolution(t0::Number,inival::AbstractArray{T}) where T
        TransientSolution([copy(inival)], [t0])
end


function make_transientsol(;nt=10,M=3,N=20)
    makevec(k)=[ k+i*j for i=1:M,j=1:N]
    sol=TransientSolution([makevec(0)], [0])
    for k=1:nt
        append!(sol,k,makevec(k))
    end
    sol
end


function main()
    s=make_transientsol()
    s[1,:,1]
end

end

out_2.13

20-element Vector{Int64}:
  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20

out_2.14

11-element Vector{Vector{Int64}}:
 [1, 2, 3]
 [2, 3, 4]
 [3, 4, 5]
 [4, 5, 6]
 [5, 6, 7]
 [6, 7, 8]
 [7, 8, 9]
 [8, 9, 10]
 [9, 10, 11]
 [10, 11, 12]
 [11, 12, 13]