# New to Julia

**URL:** https://discourse.julialang.org/c/first-steps/8.md?page=55

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**Page:** 56

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## [Test a local package](https://discourse.julialang.org/t/test-a-local-package/109974)

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**Author:** [@gitboy16](https://discourse.julialang.org/u/gitboy16)\
**Replies:** 3\
**Last updated:** [February 9, 2024, 12:22pm UTC](https://discourse.julialang.org/t/test-a-local-package/109974 "2024-02-09T12:22:16Z")

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Hi, I was wondering if there is something like cargo test in the Julia world? I would like to test a local package directly from the command line without having to open the REPL or having to type something like: julia…

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## [Julia Dependencies for PYSR](https://discourse.julialang.org/t/julia-dependencies-for-pysr/105927)

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**Author:** [@ranjan509](https://discourse.julialang.org/u/ranjan509)\
**Replies:** 35\
**Last updated:** [February 8, 2024, 5:49pm UTC](https://discourse.julialang.org/t/julia-dependencies-for-pysr/105927 "2024-02-08T17:49:09Z")

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I am trying to install Julia dependencies for PYSR and I am getting following message . HOW DO I RESOLVE THIS? JuliaError: Exception ‘GitError(Code:ERROR, Class:SSL, Your Julia is built with a SSL/TLS engine that libgit…

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## [Clarify the documentation about modifying module variables](https://discourse.julialang.org/t/clarify-the-documentation-about-modifying-module-variables/109668)

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**Author:** [@benibilme](https://discourse.julialang.org/u/benibilme)\
**Replies:** 15\
**Last updated:** [February 8, 2024, 5:39pm UTC](https://discourse.julialang.org/t/clarify-the-documentation-about-modifying-module-variables/109668 "2024-02-08T17:39:04Z")

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There is weird description without any example in the documentation. Julia 1.10 Global-Scope definition Note that while variable bindings can be read externally, they can only be changed within the module to which they…

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## [Memory usage](https://discourse.julialang.org/t/memory-usage/109873)

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**Author:** [@emily](https://discourse.julialang.org/u/emily)\
**Replies:** 3\
**Last updated:** [February 7, 2024, 5:14pm UTC](https://discourse.julialang.org/t/memory-usage/109873 "2024-02-07T17:14:05Z")

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Hi! I am trying to understand when memory allocations are cleared. When I run a problem requiring large memory use, I have discovered that it is not freed until I use the garbage collector (GC.gc()), or shut down the RE…

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## [IOError: connect: no such file or directory (ENOENT) at VSCode startup](https://discourse.julialang.org/t/ioerror-connect-no-such-file-or-directory-enoent-at-vscode-startup/109288)

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**Author:** [@TimG](https://discourse.julialang.org/u/TimG)\
**Replies:** 1\
**Last updated:** [February 7, 2024, 4:29pm UTC](https://discourse.julialang.org/t/ioerror-connect-no-such-file-or-directory-enoent-at-vscode-startup/109288 "2024-02-07T16:29:24Z")

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I use VSCode on Win10. Every time I start up VSCode from scratch, before I do anything, I get the following error. I’ve had it for a few days but I have no idea what I did to trigger it. How can I make it go away? \* H…

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## [Similarity of Julia to Asymptote Programming Language](https://discourse.julialang.org/t/similarity-of-julia-to-asymptote-programming-language/109801)

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**Author:** [@brombo](https://discourse.julialang.org/u/brombo)\
**Replies:** 4\
**Last updated:** [February 6, 2024, 4:59pm UTC](https://discourse.julialang.org/t/similarity-of-julia-to-asymptote-programming-language/109801 "2024-02-06T16:59:30Z")

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I am just getting started in Julia but am very familiar with the Asymptote graphics program scripting language - Asymptote It seems to me that the Asymptote language has many of Julia’s features and is similar (nowhere…

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## [Profiler doesn't show Threads](https://discourse.julialang.org/t/profiler-doesnt-show-threads/109774)

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**Author:** [@dbrohl](https://discourse.julialang.org/u/dbrohl)\
**Replies:** 6\
**Last updated:** [February 6, 2024, 2:45pm UTC](https://discourse.julialang.org/t/profiler-doesnt-show-threads/109774 "2024-02-06T14:45:52Z")

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I want to use multithreading in a project. I use Julia in VS Code and use the build-in profiler of the VSCode extension. The 8 threads appear in the profiler dropdown menu, but all threads except the first only have one …

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## [Why are the types in this example different?](https://discourse.julialang.org/t/why-are-the-types-in-this-example-different/109811)

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**Author:** [@Daniel\_Lincke](https://discourse.julialang.org/u/Daniel_Lincke)\
**Replies:** 1\
**Last updated:** [February 6, 2024, 2:33pm UTC](https://discourse.julialang.org/t/why-are-the-types-in-this-example-different/109811 "2024-02-06T14:33:39Z")

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f0(x :: Float32) = 1f0 f1(p :: Float32) = function(x :: Float32); return (x+p) end println(typeof(\[f0,f1(1.0f0)\])) println(typeof(\[f1(0.0f0),f1(1.0f0)\])) this results in Vector{Function} Vector{var"#1#2"{Float32}…

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## [Getting the eigen spectrum of a large matrix (representing a microgrid)](https://discourse.julialang.org/t/getting-the-eigen-spectrum-of-a-large-matrix-representing-a-microgrid/109781)

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**Author:** [@Tony\_avito](https://discourse.julialang.org/u/Tony_avito)\
**Replies:** 4\
**Last updated:** [February 6, 2024, 10:36am UTC](https://discourse.julialang.org/t/getting-the-eigen-spectrum-of-a-large-matrix-representing-a-microgrid/109781 "2024-02-06T10:36:54Z")

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Hello, I am really newb in Julia. I am looking to see a solution for finding the eigenvalues (eigen spectrum) of a microgrid. The grid matriz is not that big (47x47). I will be using some symbolic variables related to …

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## [Function and no method matching](https://discourse.julialang.org/t/function-and-no-method-matching/109760)

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**Author:** [@mary](https://discourse.julialang.org/u/mary)\
**Replies:** 2\
**Last updated:** [February 5, 2024, 9:30pm UTC](https://discourse.julialang.org/t/function-and-no-method-matching/109760 "2024-02-05T21:30:46Z")

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Hi, I am writing this function in gridap and I got the error. Is there any suggestions how to solve this? function dψP(uh,ψPlusnext\_in,hh\_in) h\_in = hh\_in if h\_in \> ψPlusnext\_in dp\_out = project(CellSta…

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## [Sub2ind on julia](https://discourse.julialang.org/t/sub2ind-on-julia/109717)

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**Author:** [@Afonso\_Britto](https://discourse.julialang.org/u/Afonso_Britto)\
**Replies:** 6\
**Last updated:** [February 5, 2024, 3:39pm UTC](https://discourse.julialang.org/t/sub2ind-on-julia/109717 "2024-02-05T15:39:38Z")

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I have this matlab code I want to convert it to julia, but there is no sub2ind in julia. Does anyone have any ideia how i can translate it? ‘’’ for c = 1:num\_channels l1\_c = sub2ind(size(SAT), row\_indices, l\_idx, …

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## [Solving ODE using RK4](https://discourse.julialang.org/t/solving-ode-using-rk4/109697)

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**Author:** [@Ahad\_Jhumka](https://discourse.julialang.org/u/Ahad_Jhumka)\
**Replies:** 7\
**Last updated:** [February 5, 2024, 2:01pm UTC](https://discourse.julialang.org/t/solving-ode-using-rk4/109697 "2024-02-05T14:01:47Z")

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I have a series of ODE which I want to solve in Julia Programming Language. Anyone have the coding for RK4 solver. Thanks

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## [Why does JET say this leads to a dispatch error?](https://discourse.julialang.org/t/why-does-jet-say-this-leads-to-a-dispatch-error/109684)

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**Author:** [@Ahmed\_Salih](https://discourse.julialang.org/u/Ahmed_Salih)\
**Replies:** 11\
**Last updated:** [February 4, 2024, 11:12pm UTC](https://discourse.julialang.org/t/why-does-jet-say-this-leads-to-a-dispatch-error/109684 "2024-02-04T23:12:48Z")

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Hello! I am using JET to improve my package. I have a function looking like this: function ResetArrays!(arrays...) @inbounds for array in arrays fill!(array,zero(eltype(array))) end end Which I feed in…

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## [Rayshader?](https://discourse.julialang.org/t/rayshader/109710)

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**Author:** [@dlpnet](https://discourse.julialang.org/u/dlpnet)\
**Replies:** 2\
**Last updated:** [February 4, 2024, 10:12pm UTC](https://discourse.julialang.org/t/rayshader/109710 "2024-02-04T22:12:25Z")

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Hello, I am brand new to Julia and exploring the possibilities. Is there any equivalent for Rayshader (https://www.rayshader.com/) in Julia? Thanks

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## [Error while running julia executable](https://discourse.julialang.org/t/error-while-running-julia-executable/109699)

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**Author:** [@ShrutiD](https://discourse.julialang.org/u/ShrutiD)\
**Replies:** 2\
**Last updated:** [February 4, 2024, 4:38pm UTC](https://discourse.julialang.org/t/error-while-running-julia-executable/109699 "2024-02-04T16:38:36Z")

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Hi, I’m new to Julia and I was trying to build and run the executable from the Julia directory( I’m on the master branch) I got the following error when I run ./julia LoadError: ArgumentError: Package REPL does not hav…

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## [Grayshade image into 3d array](https://discourse.julialang.org/t/grayshade-image-into-3d-array/109701)

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**Author:** [@Afonso\_Britto](https://discourse.julialang.org/u/Afonso_Britto)\
**Replies:** 0\
**Last updated:** [February 4, 2024, 3:29pm UTC](https://discourse.julialang.org/t/grayshade-image-into-3d-array/109701 "2024-02-04T15:29:11Z")

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I have this code, where I’m trying to apply a filter to an image based on another one. img is an rgb image and joint\_image is a grayshade image, I need to make the grayshade image into a 3d array, that’s why I’m using ch…

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## [At present, in what aspects is Julia still relatively weak compared to other mainstream programming languages?](https://discourse.julialang.org/t/at-present-in-what-aspects-is-julia-still-relatively-weak-compared-to-other-mainstream-programming-languages/109583)

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**Author:** [@WuSiren](https://discourse.julialang.org/u/WuSiren)\
**Replies:** 63\
**Last updated:** [February 4, 2024, 1:24am UTC](https://discourse.julialang.org/t/at-present-in-what-aspects-is-julia-still-relatively-weak-compared-to-other-mainstream-programming-languages/109583 "2024-02-04T01:24:22Z")

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At present, in what aspects is Julia still relatively weak compared to other mainstream programming languages? Or to put it another way, what aspects should Julia strengthen in the future? --A Julian with a surge of love…

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## [Is PyJulia org, e.g. juliacall (or pyjulia) Python packages maintained?](https://discourse.julialang.org/t/is-pyjulia-org-e-g-juliacall-or-pyjulia-python-packages-maintained/109277)

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**Author:** [@bdas123](https://discourse.julialang.org/u/bdas123)\
**Replies:** 36\
**Last updated:** [February 3, 2024, 10:01pm UTC](https://discourse.julialang.org/t/is-pyjulia-org-e-g-juliacall-or-pyjulia-python-packages-maintained/109277 "2024-02-03T22:01:48Z")

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Hello, I’m just checking if PyJulia is maintained or if there is a better way to call a Julia script from a Python code.

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## [Determine whether an element is in an array](https://discourse.julialang.org/t/determine-whether-an-element-is-in-an-array/109659)

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**Author:** [@jisutich](https://discourse.julialang.org/u/jisutich)\
**Replies:** 4\
**Last updated:** [February 3, 2024, 5:23pm UTC](https://discourse.julialang.org/t/determine-whether-an-element-is-in-an-array/109659 "2024-02-03T17:23:11Z")

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Hi I am thinking how to achieve similar thing to numpy’s where function in Julia. Suppose I have an array A and now I want to determine if there is any element of A belong to the regime \[a-1e-12,a+1e-12\]. If yes I want …

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## [How fill a poly object with a color gradient defined by the values inside it?](https://discourse.julialang.org/t/how-fill-a-poly-object-with-a-color-gradient-defined-by-the-values-inside-it/109667)

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**Author:** [@Midez](https://discourse.julialang.org/u/Midez)\
**Replies:** 0\
**Last updated:** [February 3, 2024, 12:31pm UTC](https://discourse.julialang.org/t/how-fill-a-poly-object-with-a-color-gradient-defined-by-the-values-inside-it/109667 "2024-02-03T12:31:47Z")

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Hello everyone, to better understand what I eagerly try to do I have attached you the data and code using DelimitedFiles, CairoMakie, Colors ol = readdlm("/Users/.../outline.txt"); vx = readdlm("/Users/.../x\_data.txt"…

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## [Wanted to learn machine learning(ML) from scrach!](https://discourse.julialang.org/t/wanted-to-learn-machine-learning-ml-from-scrach/109550)

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**Author:** [@npsasikumar](https://discourse.julialang.org/u/npsasikumar)\
**Replies:** 5\
**Last updated:** [February 2, 2024, 10:47pm UTC](https://discourse.julialang.org/t/wanted-to-learn-machine-learning-ml-from-scrach/109550 "2024-02-02T22:47:58Z")

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I am a research scholar working with the mathematical part of nonlinear dynamics. And I wanted to implement ML in research to validate the outcomes. So please suggest the materials (books, blogs, YouTube links, or any) t…

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## [WSL- install Julia using snap?](https://discourse.julialang.org/t/wsl-install-julia-using-snap/109619)

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**Author:** [@benslinux](https://discourse.julialang.org/u/benslinux)\
**Replies:** 2\
**Last updated:** [February 2, 2024, 2:04pm UTC](https://discourse.julialang.org/t/wsl-install-julia-using-snap/109619 "2024-02-02T14:04:49Z")

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Are there any issues with using snap to install Julia on WSL? It’s an easy install, but I remember last year there were some issues with 32 vs 64 bit, snap’s version being deprecated, etc… I believe these issues have bee…

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## [Function to check if Channel is full](https://discourse.julialang.org/t/function-to-check-if-channel-is-full/44795)

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**Author:** [@martincornejo](https://discourse.julialang.org/u/martincornejo)\
**Replies:** 3\
**Last updated:** [February 2, 2024, 1:24pm UTC](https://discourse.julialang.org/t/function-to-check-if-channel-is-full/44795 "2024-02-02T13:24:59Z")

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The function isready(ch) checks if Channel ch has any stored value. Is there a function to check if a Channel is full?

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## [Run(\`start\`) doesn't work](https://discourse.julialang.org/t/run-start-doesnt-work/109552)

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**Author:** [@rmsmsgood](https://discourse.julialang.org/u/rmsmsgood)\
**Replies:** 4\
**Last updated:** [February 2, 2024, 12:01pm UTC](https://discourse.julialang.org/t/run-start-doesnt-work/109552 "2024-02-02T12:01:20Z")

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I used my python program to open webpage automatically. import os os.system("start https://discourse.julialang.org/") But julia version can’t, even git commands are working. Any help? PS C:\\Users\\rmsms\> start https://…

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## [Explain generators](https://discourse.julialang.org/t/explain-generators/109573)

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**Author:** [@Anders\_Holtsberg](https://discourse.julialang.org/u/Anders_Holtsberg)\
**Replies:** 11\
**Last updated:** [February 2, 2024, 5:03am UTC](https://discourse.julialang.org/t/explain-generators/109573 "2024-02-02T05:03:45Z")

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I am trying to understand how to implement a simple generator so that I can traverse my graphs in different ways. It boils down to the example below. In Lua - which I come from - it works without any ado, but in Julia it…

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## [Fatal Python error when running Julia on mac m1 VS Code](https://discourse.julialang.org/t/fatal-python-error-when-running-julia-on-mac-m1-vs-code/109540)

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**Author:** [@Salvator](https://discourse.julialang.org/u/Salvator)\
**Replies:** 9\
**Last updated:** [February 1, 2024, 7:27pm UTC](https://discourse.julialang.org/t/fatal-python-error-when-running-julia-on-mac-m1-vs-code/109540 "2024-02-01T19:27:58Z")

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Hi everyone! I’m kinda used to Julia given some courses on stochastic simulations and I have never got a problem. Now I’m struggling with an error which makes the kernel to crash: I’m running Julia1.6.3 on VS Code and w…

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## [Tools to Analyze Long Julia Compilation Times](https://discourse.julialang.org/t/tools-to-analyze-long-julia-compilation-times/109510)

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**Author:** [@Nimrais](https://discourse.julialang.org/u/Nimrais)\
**Replies:** 4\
**Last updated:** [February 1, 2024, 1:17pm UTC](https://discourse.julialang.org/t/tools-to-analyze-long-julia-compilation-times/109510 "2024-02-01T13:17:25Z")

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Could anyone recommend the best tool for analyzing Julia’s compilation process? I’m facing an issue where my code runs quickly, but the compilation time is excessively slow. I’ve looked into generic advice regarding Type…

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## [Looking for feedback - minimal repo that calls Julia code from Python](https://discourse.julialang.org/t/looking-for-feedback-minimal-repo-that-calls-julia-code-from-python/109571)

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**Author:** [@aramend](https://discourse.julialang.org/u/aramend)\
**Replies:** 0\
**Last updated:** [February 1, 2024, 1:09pm UTC](https://discourse.julialang.org/t/looking-for-feedback-minimal-repo-that-calls-julia-code-from-python/109571 "2024-02-01T13:09:44Z")

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Hi all! I have created a minimal repository where a Python API function calls an underlying Julia function and returns the computed result in Python land. If you want to try it, make run should work for you on linux or …

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## [Development package dependencies](https://discourse.julialang.org/t/development-package-dependencies/109557)

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**Author:** [@JoseKling](https://discourse.julialang.org/u/JoseKling)\
**Replies:** 7\
**Last updated:** [February 1, 2024, 11:44am UTC](https://discourse.julialang.org/t/development-package-dependencies/109557 "2024-02-01T11:44:51Z")

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Hello all, I am currently developing a package, we can call it A, that depends on a second package B, which is also under development. In package A’s environment I ran \]dev B to add B as a dependency of A. After that B…

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## [Gradient check by zygote](https://discourse.julialang.org/t/gradient-check-by-zygote/109225)

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**Author:** [@mary](https://discourse.julialang.org/u/mary)\
**Replies:** 6\
**Last updated:** [January 31, 2024, 10:29pm UTC](https://discourse.julialang.org/t/gradient-check-by-zygote/109225 "2024-01-31T22:29:00Z")

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Hi I am using Julia Gridap library to calculate gradients. I wrote the rules for gradients but when i check the gradients with running finite difference manually. they are different. I check equations multiple time and …

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