On Fri, 2014-11-14 at 04:56, Amuthan A. Ramabathiran <apar...@gmail.com> wrote:
> Hello,
>
> I ran into this problem recently:
>
> julia> a = Array{Int,1}[]
> 0-element Array{Array{Int64,1},1}
>
> julia> b = zeros(Int,2)
> 2-element Array{Int64,1}:
> 0
> 0
>
> julia> b[1] = 1
> 1
>
> julia> push!(a,b)
> 1-element Array{Array{Int64,1},1}:
> [1,0]
>
> julia> b[1] = -1
> -1
>
> julia> push!(a,b)
> 2-element Array{Array{Int64,1},1}:
> [-1,0]
> [-1,0]
>
>
> I'm wondering why a[1] changes to [-1,0]. Is it because only a reference to
> b is stored when it is pushed to a? Are there any simple solutions to avoid
> this?
Correct. You can copy b before inserting:
push!(a,copy(b))
I think there is an entry in the FAQ about mutability.
