# How to open sub-directory of HDF5 file in Julia?

**URL:** <https://discourse.julialang.org/t/how-to-open-sub-directory-of-hdf5-file-in-julia/115010>\
**Category:** Data\
**Tags:** hdf5\
**Created:** [May 31, 2024, 12:20pm UTC](https://discourse.julialang.org/t/how-to-open-sub-directory-of-hdf5-file-in-julia/115010 "2024-05-31T12:20:40Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![raman\_kumar](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/raman_kumar/32/26782_2.png) [@raman\_kumar](https://discourse.julialang.org/u/raman_kumar)\
**Post date:** [May 31, 2024, 12:20pm UTC](https://discourse.julialang.org/t/how-to-open-sub-directory-of-hdf5-file-in-julia/115010/1 "2024-05-31T12:20:40Z")

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I want to open sub-directory of HDF5 file in Julia?

 ![image](https://global.discourse-cdn.com/julialang/original/3X/a/e/aef45381052f4d641e0590b10c617e1cca21cd78.png)  
For example- how can i open `"Coordinates"` folder using HDF5.jl?

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**Author:** ![stevengj](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/stevengj/32/71_2.png) [@stevengj](https://discourse.julialang.org/u/stevengj)\
**Post date:** [May 31, 2024, 2:25pm UTC](https://discourse.julialang.org/t/how-to-open-sub-directory-of-hdf5-file-in-julia/115010/2 "2024-05-31T14:25:50Z")

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A “subdirectory” is called a “group” in HDF5. See [the HDF5 documentation on opening groups](https://juliaio.github.io/HDF5.jl/stable/#Opening-and-closing-objects).

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**Author:** ![raman\_kumar](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/raman_kumar/32/26782_2.png) [@raman\_kumar](https://discourse.julialang.org/u/raman_kumar)\
**Post date:** [May 31, 2024, 2:56pm UTC](https://discourse.julialang.org/t/how-to-open-sub-directory-of-hdf5-file-in-julia/115010/3 "2024-05-31T14:56:40Z")

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What should i type in terminal to open that group?

 ![image](https://global.discourse-cdn.com/julialang/original/3X/1/0/10bb7d0a70ba062b68c53f43cea37451d54598ad.png)

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**Author:** ![mkitti](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mkitti/32/12459_2.png) [@mkitti](https://discourse.julialang.org/u/mkitti)\
**Post date:** [May 31, 2024, 3:17pm UTC](https://discourse.julialang.org/t/how-to-open-sub-directory-of-hdf5-file-in-julia/115010/4 "2024-05-31T15:17:57Z")

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`Coordinates` is not a group. That is an attribute. See either `attrs` or `attributes`.

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**Author:** ![raman\_kumar](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/raman_kumar/32/26782_2.png) [@raman\_kumar](https://discourse.julialang.org/u/raman_kumar)\
**Post date:** [May 31, 2024, 3:22pm UTC](https://discourse.julialang.org/t/how-to-open-sub-directory-of-hdf5-file-in-julia/115010/5 "2024-05-31T15:22:58Z")

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What attribute contains? How to open it?

 ![image](https://global.discourse-cdn.com/julialang/original/3X/c/9/c97e3a604f3e206109c379f182b8428a02c37419.png)

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<div class="post-metadata">

**Author:** ![mkitti](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mkitti/32/12459_2.png) [@mkitti](https://discourse.julialang.org/u/mkitti)\
**Post date:** [May 31, 2024, 3:27pm UTC](https://discourse.julialang.org/t/how-to-open-sub-directory-of-hdf5-file-in-julia/115010/6 "2024-05-31T15:27:38Z")

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```julia-repl
julia> data = h5open("data.h5", "r")
🗂️ HDF5.File: (read-only) data.h5
└─ 🏷️ Coordinates

julia> attrs(data)
AttributeDict of HDF5.Group: / (file: data.h5) with 1 attribute:
  "Coordinates" => [12, 75]

julia> attrs(data)["Coordinates"]
2-element Vector{Int64}:
 12
 75

```

Or with `attributes`:

```julia-repl
julia> attributes(data)
🗂️ Attributes of HDF5.File: (read-only) data.h5
└─ 🏷️ Coordinates

julia> attributes(data)["Coordinates"]
🏷️ HDF5.Attribute: Coordinates

julia> attributes(data)["Coordinates"][]
2-element Vector{Int64}:
 12
 75

julia> read(attributes(data)["Coordinates"])
2-element Vector{Int64}:
 12
 75

```