在Julia中，我想将定义为2D数组向量的数据转换为矩阵的2D数组。 如下例所示，我想将数据s转换为数据t，但目前尚未成功。 我该怎么处理这种情况？
julia> s = [[1 2 3], [4 5 6], [7 8 9]]
3-element Array{Array{Int64,2},1}:
[1 2 3]
[4 5 6]
[7 8 9]
julia> t = [[1 2 3]; [4 5 6]; [7 8 9]]
3××3 Array{Int64,2}:
1 2 3
4 5 6
7 8 9
julia> s |> typeof
Array{Array{Int64,2},1}
julia> t |> typeof
Array{Int64,2}
julia> convert(Array{Int64, 2}, s)
ERROR: MethodError: Cannot `convert` an object of type Array{Array{Int64,2},1} to an object of type Array{Int64,2}
This may have arisen from a call to the constructor Array{Int64,2}(...),
since type constructors fall back to convert methods.
julia> reshape(s, 3, 3)
ERROR: DimensionMismatch("new dimensions (3,3) must be consistent with array size 3")
in reshape(::Array{Array{Int64,2},1}, ::Tuple{Int64,Int64}) at .\array.jl:113
in reshape(::Array{Array{Int64,2},1}, ::Int64, ::Int64, ::Vararg{Int64,N}) at .\reshapedarray.jl:39
如下例所示，如果您将二维数组或一维数组定义为源数据，我可以成功地将它们重塑为矩阵的二维数组。
julia> u = [1 2 3 4 5 6 7 8 9]
1××9 Array{Int64,2}:
1 2 3 4 5 6 7 8 9
julia> u |> typeof
Array{Int64,2}
julia> reshape(u, 3, 3)
3××3 Array{Int64,2}:
1 4 7
2 5 8
3 6 9
julia> v = [1, 2, 3, 4, 5, 6, 7, 8, 9]
9-element Array{Int64,1}:
1
2
3
4
5
6
7
8
9
julia> v |> typeof
Array{Int64,1}
julia> reshape(v, 3, 3)
3××3 Array{Int64,2}:
1 4 7
2 5 8
3 6 9