# Changing number format when concatenating

**URL:** <https://discourse.julialang.org/t/changing-number-format-when-concatenating/40084>\
**Category:** General Usage\
**Tags:** numbers\
**Created:** [May 24, 2020, 5:27pm UTC](https://discourse.julialang.org/t/changing-number-format-when-concatenating/40084 "2020-05-24T17:27:07Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![sergevic](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sergevic/32/9958_2.png) [@sergevic](https://discourse.julialang.org/u/sergevic)\
**Post date:** [May 24, 2020, 5:27pm UTC](https://discourse.julialang.org/t/changing-number-format-when-concatenating/40084/1 "2020-05-24T17:27:07Z")

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I have an integer Array `a=[1,2,3,4]` and a floating Array `b=[0.5, 0.671, 0.875, 1.5]`. When I try to concatenate with `cat(dims=2,a,b)`, I obtain what I want, but the integer numbers are now floating numbers:

> 4×2 Array{Float64,2}:  
> 1.0 0.5  
> 2.0 0.671  
> 3.0 0.875  
> 4.0 1.5

How can I obtain the same concatenated Array but with integers in the first column?

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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:** [May 24, 2020, 5:31pm UTC](https://discourse.julialang.org/t/changing-number-format-when-concatenating/40084/2 "2020-05-24T17:31:46Z")

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Don’t know if this is the best but you could promote one of the arrays to `Any`

```julia
julia> cat(Vector{Any}(a), b; dims=2)
4×2 Array{Any,2}:
 1 0.5
 2 0.671
 3 0.875
 4 1.5

```

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<div class="post-metadata">

**Author:** ![sergevic](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sergevic/32/9958_2.png) [@sergevic](https://discourse.julialang.org/u/sergevic)\
**Post date:** [May 24, 2020, 5:39pm UTC](https://discourse.julialang.org/t/changing-number-format-when-concatenating/40084/3 "2020-05-24T17:39:06Z")

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Thank you for the quick answer 🙂 The concatenated Array is not big, so I Think it can do the trick 🙂 I will test if the steps that need that Array aren’t affected!

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**Author:** ![mcabbott](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mcabbott/32/6603_2.png) [@mcabbott](https://discourse.julialang.org/u/mcabbott)\
**Post date:** [May 24, 2020, 6:39pm UTC](https://discourse.julialang.org/t/changing-number-format-when-concatenating/40084/4 "2020-05-24T18:39:54Z")

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Comprehensions seem to go by promote\_typejoin instead, so you could do this:

```julia
julia> [x[i] for i in 1:4, x in (a,b)]
4×2 Array{Real,2}:
 1 0.5
 2 0.671
 3 0.875
 4 1.5

```

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<div class="post-metadata">

**Author:** ![sergevic](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sergevic/32/9958_2.png) [@sergevic](https://discourse.julialang.org/u/sergevic)\
**Post date:** [May 24, 2020, 7:06pm UTC](https://discourse.julialang.org/t/changing-number-format-when-concatenating/40084/5 "2020-05-24T19:06:20Z")

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Thank you! Both solutions work for me 🙂

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**Author:** ![dpsanders](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dpsanders/32/3573_2.png) [@dpsanders](https://discourse.julialang.org/u/dpsanders)\
**Post date:** [May 24, 2020, 7:21pm UTC](https://discourse.julialang.org/t/changing-number-format-when-concatenating/40084/6 "2020-05-24T19:21:46Z")

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> [@sergevic](#):
>
> [0.5, 0.671, 0.875, 1.5]

You can do

```julia
julia> Real[a b]
4×2 Array{Real,2}:
 1 0.5
 2 0.671
 3 0.875
 4 1.5

```

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<div class="post-metadata">

**Author:** ![sergevic](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sergevic/32/9958_2.png) [@sergevic](https://discourse.julialang.org/u/sergevic)\
**Post date:** [May 24, 2020, 8:59pm UTC](https://discourse.julialang.org/t/changing-number-format-when-concatenating/40084/7 "2020-05-24T20:59:59Z")

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Another good option 🙂