Suprising assignment behavior


This is confusing (on 0.5.0): imagine calling a function that returns 2 values in a loop:

julia> f()=1,2
f (generic function with 1 method)

julia> a,b=f()

julia> a

julia> b
julia> u=v=zeros(2,1);i=1;

julia> u[i],v[i]=f()

I was surprised by this:

julia> u
2×1 Array{Float64,2}:

julia> v
2×1 Array{Float64,2}:

I suppose this is related to the immutability of tuples and not a bug, but it is really surprising.

Edit: Never mind. u and v are the same arrays of course. How does one delete posts?


Your problem is here… u and v point to the same exact matrix, so when u[i],v[i]=f() is unpacked, it first sets the matrix item to 1, and then to 2. Since there’s only one matrix, they both show the 2.


Thanks. Just figured it out myself but you beat me to it :slight_smile:


When a solution has been found and posted (even if by yourself), please mark the relevant post ad the solution by pressing the corresponding button.


and the corresponding button is? I see ‘bookmark’, ‘share’, ‘flag’ and ‘reply’ and ‘like’…


There should be one with a check mark (tick mark).


Presumably, only the OP can see that box.


That would make some sense, but even on the threads i started i don’t see this? Might be a browser issue?


Ah, that could be true.