Hello, I want to define a global variable inside a module. This global variable can be set by the user and the behaviour (the returned value) of the functions inside the module depends on this global variable. For example: module M global AMP set_amp(x) = (AMP = x) func1(x; amp) = amp * x …

Make a Simulation struct that contains lambda and have functions operate on that object.

The performance would be similar as long as you get rid of global variables.

I created the Jupyter and Pluto notebooks with the same contents as below: Jupyter notebooks: Julia ≥ v1.7: https://github.com/genkuroki/public/blob/main/0011/Problem-Algorithm-Solver%20pattern%202021-07-16.ipynb Julia v1.6: https://github.com/genkuroki/public/blob/main/0011/Problem-Algorithm-So…

Globals make your code unusable in multithreading. If someone tries to solve a physics problem with your package in parallel for different lengths and you use globals… It will Bork heavily. Use the suggested approaches above and it will be possible to multithread!

Thanks for your answer. Although my case is easier than the example you provided, I learn a lot from your example. What is the purpose of using the 4 different type parameters (G, Y0, V0, TS) in the declaration of Problem structure? struct Problem{G, Y0, V0, TS} g::G = 9.80665 y0::Y0 = 0.…

[image] ykkan: struct Problem{T} g::T = 9.80665 y0::T = 0.0 v0::T = 30.0 tspan::Tuple{T, T} = (0.0, 8.0) end I created the Jupyter notebook with this change: https://github.com/genkuroki/public/blob/main/0011/Problem-Algorithm-Solver%20pattern%202021-07-16%20-%20Make%20Probl…

[image] genkuroki: Composability/Extensibility of the Julia ecosystem: @genkuroki , thanks for this outstanding post, a great service to promote Julia language IMHO. As an exercise, added to your code the different physical units using Unitful and UnitfulRecipes. It worked everywhere at the f…

By saying multithreading, do you mean things like openMP? However, if use MPI instead, will global variables still have such problems you mentioned?

[image] genkuroki: """Problem type""" Base.@kwdef struct Problem{G, Y0, V0, TS} g::G = 9.80665 y0::Y0 = 0.0 v0::V0 = 30.0 tspan::TS = (0.0, 8.0) end Is it always recommended to parameterize the type of a struct? For instance, if a struct has 10 fields, then do we need to speci…

Sorry for a stupid question, what does the … mean in using ..FreeFall I know if I write a module called FreeFall.jl, I can do include("FreeFall.jl") using .FreeFall But what does the … do in using …FreeFall? Thanks!

Function depending on the global variable inside module

New to Julia

CRquantum August 5, 2021, 4:32am 24

Thank you!
Yes, I was thinking it must be something related with shared memory stuff that can cause issue for global variable. For MPI, it seems using global variable is safe because each core are independent.

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Function depending on the global variable inside module

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