# Why is Vector{Float16} \<: AbstractVector{AbstractFloat} being false?

**URL:** <https://discourse.julialang.org/t/why-is-vector-float16-abstractvector-abstractfloat-being-false/25755>\
**Category:** New to Julia\
**Created:** [June 27, 2019, 9:12am UTC](https://discourse.julialang.org/t/why-is-vector-float16-abstractvector-abstractfloat-being-false/25755 "2019-06-27T09:12:53Z")\
**Posts on this page:** 2\
**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:** [June 27, 2019, 9:12am UTC](https://discourse.julialang.org/t/why-is-vector-float16-abstractvector-abstractfloat-being-false/25755/1 "2019-06-27T09:12:53Z")

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```julia
julia> Float16 <: AbstractFloat
true

julia> Vector{Float16} <: AbstractVector
true

julia> Vector{Float16} <: AbstractVector{AbstractFloat}
false

```

why?

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<div class="post-metadata">

**Author:** ![simeonschaub](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/simeonschaub/32/216566_2.png) [@simeonschaub](https://discourse.julialang.org/u/simeonschaub)\
**Post date:** [June 27, 2019, 9:24am UTC](https://discourse.julialang.org/t/why-is-vector-float16-abstractvector-abstractfloat-being-false/25755/2 "2019-06-27T09:24:04Z")

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See [https://docs.julialang.org/en/v1.1/manual/types/index.html#Parametric-Composite-Types-1](https://docs.julialang.org/en/v1.1/manual/types/index.html#Parametric-Composite-Types-1). `AbstractVector{<:AbstractFloat}`, or, equivalently, `AbstractVector{T} where T<:AbstractFloat` should do what you want.