# Transferring data structures between Julia files?
**URL:** https://discourse.julialang.org/t/transferring-data-structures-between-julia-files/49636
**Category:** General Usage
**Created:** [November 5, 2020, 6:57pm UTC](https://discourse.julialang.org/t/transferring-data-structures-between-julia-files/49636 "2020-11-05T18:57:21Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@BLI](https://discourse.julialang.org/u/BLI)
#### Post date: [November 5, 2020, 6:57pm UTC](https://discourse.julialang.org/t/transferring-data-structures-between-julia-files/49636/1 "2020-11-05T18:57:21Z")
I need to transfer information between two Julia files (or: between two Jupyter notebooks). Examples of data structures:
- A dictionary with keys “a”, “b”, “c”, etc., where the value for each key is a tuple holding Floats, dates, interpolation functions, etc.
- It is kind of ugly to write this into a \*.jl file to include the file in the other document.
**Question** : is there a simpler way? Can I store the data in a Json file and read the JSON file in the other document? If so:
- Which package?
Example: suppose I have the following data structure:
```julia
using Dates, DataInterpolations
#
x = 3
t = Date(2020,11,5)
X = 0:20
Y = sin.(X*2pi/10)
y = ConstantInterpolation(Y,X)
#
d = Dict("a" => (x,t,y))
# ...
merge(d,Dict("b") => ...)
```
If I want to store this as a \*.jl file, I cannot save/write the dictionary `d`, but instead need to build it up from scratch in write statements… something like:
```julia
open("my_dictionary.jl", "w") do f
write(f,"t_y = $(Year(t).value) \n")
write(f,"t_m = $(Month(t).value) \n")
write(f,"t_d = $(Day(t).value) \n")
write(f,"X = $(X) \n")
write(f,"Y = $(Y) \n")
#
write(f,"y = ConstantInterpolation(Y,X) \n")
write(f,"d = Dict("a",($(x),Date(t_y,t_m,t_d),y)) \n")
end
```
When I run this code, I can include the file in another Jupyter notebook, and get back the dictionary:
```julia
using Dates, DataInterpolations, Plots
include("my_dictionary.jl")
plot(d["a"][3])
```
I _assume_ there is a simpler way, so that I only need to write something like
```julia
save("my_dictionary",$d)
```
or something like this…
But what is the best package to do this?
---
### Author:  [@dilumaluthge](https://discourse.julialang.org/u/dilumaluthge)
#### Post date: [November 5, 2020, 7:10pm UTC](https://discourse.julialang.org/t/transferring-data-structures-between-julia-files/49636/2 "2020-11-05T19:10:48Z")
Maybe try the JLD2.jl or BSON.jl packages?
---
### Author:  [@BLI](https://discourse.julialang.org/u/BLI)
#### Post date: [November 5, 2020, 7:14pm UTC](https://discourse.julialang.org/t/transferring-data-structures-between-julia-files/49636/3 "2020-11-05T19:14:42Z")
OK – I’ve seen a `JSON` package, and a `JSON2` package. And then there is the `JLD` and the `JLD2` package. And a `BSON` package.
But which do you recommend? Are all maintained? Simple to use vs. comprehensive?
---
### Author:  [@dilumaluthge](https://discourse.julialang.org/u/dilumaluthge)
#### Post date: [November 5, 2020, 7:15pm UTC](https://discourse.julialang.org/t/transferring-data-structures-between-julia-files/49636/4 "2020-11-05T19:15:18Z")
I have used and like all of the following packages:
1. JLD2
2. JSON3
3. BSON
---
### Author:  [@BLI](https://discourse.julialang.org/u/BLI)
#### Post date: [November 5, 2020, 7:16pm UTC](https://discourse.julialang.org/t/transferring-data-structures-between-julia-files/49636/5 "2020-11-05T19:16:27Z")
OK – in that order? Or all are good?
---
### Author:  [@dilumaluthge](https://discourse.julialang.org/u/dilumaluthge)
#### Post date: [November 5, 2020, 7:17pm UTC](https://discourse.julialang.org/t/transferring-data-structures-between-julia-files/49636/6 "2020-11-05T19:17:11Z")
All three of the packages that I listed are good. I would recommend starting with JLD2.
---
### Author:  [@BLI](https://discourse.julialang.org/u/BLI)
#### Post date: [November 5, 2020, 7:17pm UTC](https://discourse.julialang.org/t/transferring-data-structures-between-julia-files/49636/7 "2020-11-05T19:17:48Z")
Thanks! You have limited my need to read lots of documentation :-).
---
### Author:  [@greg\_plowman](https://discourse.julialang.org/u/greg_plowman)
#### Post date: [November 5, 2020, 11:06pm UTC](https://discourse.julialang.org/t/transferring-data-structures-between-julia-files/49636/8 "2020-11-05T23:06:25Z")
You could also look at the standard library `Serialization`.
[https://docs.julialang.org/en/v1/stdlib/Serialization/](https://docs.julialang.org/en/v1/stdlib/Serialization/)
Might be suitable if you are always transferring across the same Julia versions.
---
### Author:  [@BLI](https://discourse.julialang.org/u/BLI)
#### Post date: [November 6, 2020, 8:08am UTC](https://discourse.julialang.org/t/transferring-data-structures-between-julia-files/49636/9 "2020-11-06T08:08:52Z")
I use different versions of Julia on various computers. So: v. 1.4.2 on my home computer, 1.5.1 on my other computers.
From your comment, it sounds like this might be a problem with `Serialization`? Or do you mean the problem is in Windows version vs. Mac version, etc.?