# Broadcasting warning

**URL:** <https://discourse.julialang.org/t/broadcasting-warning/15795>\
**Category:** New to Julia\
**Created:** [October 2, 2018, 3:06pm UTC](https://discourse.julialang.org/t/broadcasting-warning/15795 "2018-10-02T15:06:58Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![tomtom](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/tomtom/32/5106_2.png) [@tomtom](https://discourse.julialang.org/u/tomtom)\
**Post date:** [October 2, 2018, 3:06pm UTC](https://discourse.julialang.org/t/broadcasting-warning/15795/1 "2018-10-02T15:06:58Z")

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I got a warning when trying to do some broadcasting:

```julia
julia> 5.0 .* a
┌ Warning: broadcast will default to iterating over its arguments in the future. Wrap arguments of
│ type `x::mystruct` with `Ref(x)` to ensure they broadcast as "scalar" elements.
│ caller = ip:0x0
└ @ Core :-1

```

where `a` is a `mystruct` typed object.

what does the warning mean? how could I get rid of it? thanks.

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**Author:** ![kristoffer.carlsson](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/kristoffer.carlsson/32/22_2.png) [@kristoffer.carlsson](https://discourse.julialang.org/u/kristoffer.carlsson)\
**Post date:** [October 2, 2018, 3:43pm UTC](https://discourse.julialang.org/t/broadcasting-warning/15795/2 "2018-10-02T15:43:04Z")

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Use `5.0 .* (a,)` or `5.0 .* Ref(a)` or define `Base.broadcastable(a::A) = Ref(a)`

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**Author:** ![tomtom](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/tomtom/32/5106_2.png) [@tomtom](https://discourse.julialang.org/u/tomtom)\
**Post date:** [October 3, 2018, 3:24am UTC](https://discourse.julialang.org/t/broadcasting-warning/15795/3 "2018-10-03T03:24:01Z")

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thanks.

but … what does it mean???🤔

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**Author:** ![kristoffer.carlsson](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/kristoffer.carlsson/32/22_2.png) [@kristoffer.carlsson](https://discourse.julialang.org/u/kristoffer.carlsson)\
**Post date:** [October 3, 2018, 12:24pm UTC](https://discourse.julialang.org/t/broadcasting-warning/15795/4 "2018-10-03T12:24:08Z")

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It means that broadcasting will default to iterating instead of treating it as a scalar in 1.0.

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**Author:** ![Ajaychat3](https://avatars.discourse-cdn.com/v4/letter/a/ecd19e/32.png) [@Ajaychat3](https://discourse.julialang.org/u/Ajaychat3)\
**Post date:** [October 3, 2018, 12:31pm UTC](https://discourse.julialang.org/t/broadcasting-warning/15795/5 "2018-10-03T12:31:40Z")

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@kristoffer.carlsson: I am on Julia 1.0 win 10 environment. Here is what I get.

```julia
julia> a=[1,2,3,4,5]
5-element Array{Int64,1}:
 1
 2
 3
 4
 5

julia> 5.0 .*a
5-element Array{Float64,1}:
  5.0
 10.0
 15.0
 20.0
 25.0

julia> a=(1,2,3,4,5)
(1, 2, 3, 4, 5)

julia> 5.0 .*a
(5.0, 10.0, 15.0, 20.0, 25.0)

```

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<div class="post-metadata">

**Author:** ![kristoffer.carlsson](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/kristoffer.carlsson/32/22_2.png) [@kristoffer.carlsson](https://discourse.julialang.org/u/kristoffer.carlsson)\
**Post date:** [October 3, 2018, 12:32pm UTC](https://discourse.julialang.org/t/broadcasting-warning/15795/6 "2018-10-03T12:32:35Z")

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Sure but the first post said

> [@tomtom](#):
>
> where `a` is a `mystruct` typed object.