# General Usage

**URL:** https://discourse.julialang.org/c/usage/6.md?page=43

[Latest](https://discourse.julialang.org/latest.md) · [Categories](https://discourse.julialang.org/categories.md) · [Tags](https://discourse.julialang.org/tags.md)

**Page:** 44

---

## [Mapping NodeIDs to DOFs in Ferrite.jl V1.1.0](https://discourse.julialang.org/t/mapping-nodeids-to-dofs-in-ferrite-jl-v1-1-0/131975)

<div class="topic-metadata">

**Author:** [@noetheriankoala](https://discourse.julialang.org/u/noetheriankoala)\
**Replies:** 2\
**Last updated:** [August 31, 2025, 5:37pm UTC](https://discourse.julialang.org/t/mapping-nodeids-to-dofs-in-ferrite-jl-v1-1-0/131975 "2025-08-31T17:37:38Z")

</div>

Hello! What is the canonical way to get the DOFs corresponding to a specific node in Ferrite.jl? I am sure there is a way to iterate over all cells to look for which cells share which nodes, but this seems cumbersome for…

---

## [Minimum distance from point to linestring on earth's surface](https://discourse.julialang.org/t/minimum-distance-from-point-to-linestring-on-earths-surface/131964)

<div class="topic-metadata">

**Author:** [@droodman](https://discourse.julialang.org/u/droodman)\
**Replies:** 9\
**Last updated:** [August 31, 2025, 12:01pm UTC](https://discourse.julialang.org/t/minimum-distance-from-point-to-linestring-on-earths-surface/131964 "2025-08-31T12:01:56Z")

</div>

Say I have a shapefile representing the highway network in South America and want to find the minimum geographic distance from that network to another point on the continent. Is there no simple way to do this with the av…

---

## [Julia code generation LLM models?](https://discourse.julialang.org/t/julia-code-generation-llm-models/130223)

<div class="topic-metadata">

**Author:** [@Nimisha](https://discourse.julialang.org/u/Nimisha)\
**Replies:** 4\
**Last updated:** [August 30, 2025, 4:00pm UTC](https://discourse.julialang.org/t/julia-code-generation-llm-models/130223 "2025-08-30T16:00:19Z")

</div>

Can anyone help me to find best julia code generation LLM models??

---

## [Complex number support in Reactant](https://discourse.julialang.org/t/complex-number-support-in-reactant/131948)

<div class="topic-metadata">

**Author:** [@dameka](https://discourse.julialang.org/u/dameka)\
**Replies:** 1\
**Last updated:** [August 30, 2025, 2:41am UTC](https://discourse.julialang.org/t/complex-number-support-in-reactant/131948 "2025-08-30T02:41:33Z")

</div>

I am unable to find mention of complex numbers in Reactant. Does anyone know if it supports complex, or if there are common workarounds at this point? # MWE testing if Reactant supports complex numbers using Reactant f…

---

## [ERROR: UndefRefError: access to undefined reference](https://discourse.julialang.org/t/error-undefreferror-access-to-undefined-reference/68168)

<div class="topic-metadata">

**Author:** [@RaquelSantos](https://discourse.julialang.org/u/RaquelSantos)\
**Replies:** 2\
**Last updated:** [August 30, 2025, 1:46am UTC](https://discourse.julialang.org/t/error-undefreferror-access-to-undefined-reference/68168 "2025-08-30T01:46:43Z")

</div>

How to eliminate this error ERROR: UndefRefError: access to undefined reference a = 280 A = 1:a for a in A RandDeviation\[a\] = rand() end

---

## [HDR pixels: tuples vs. StaticArrays](https://discourse.julialang.org/t/hdr-pixels-tuples-vs-staticarrays/131929)

<div class="topic-metadata">

**Author:** [@rmfritz](https://discourse.julialang.org/u/rmfritz)\
**Replies:** 13\
**Last updated:** [August 29, 2025, 9:26pm UTC](https://discourse.julialang.org/t/hdr-pixels-tuples-vs-staticarrays/131929 "2025-08-29T21:26:09Z")

</div>

I’m working with an HDR pixel type, which at the moment I am representing as a tuple. I can make a case for using an SVector or MVector instead, so I wobble back and forth between leaving the code as it is and switching …

---

## [Using control flow in Reactant](https://discourse.julialang.org/t/using-control-flow-in-reactant/131946)

<div class="topic-metadata">

**Author:** [@dameka](https://discourse.julialang.org/u/dameka)\
**Replies:** 4\
**Last updated:** [August 29, 2025, 6:20pm UTC](https://discourse.julialang.org/t/using-control-flow-in-reactant/131946 "2025-08-29T18:20:58Z")

</div>

I’ve got some expensive code I’m running that I’d like to compile with Reactant. There is some control flow that’s not playing nice with Reactant. I’ve got an MWE producing a different error than my main code, but I’m ho…

---

## [Viewer for VS Code (Notebook Alternative)](https://discourse.julialang.org/t/viewer-for-vs-code-notebook-alternative/131878)

<div class="topic-metadata">

**Author:** [@Alex1](https://discourse.julialang.org/u/Alex1)\
**Replies:** 4\
**Last updated:** [August 29, 2025, 1:34pm UTC](https://discourse.julialang.org/t/viewer-for-vs-code-notebook-alternative/131878 "2025-08-29T13:34:44Z")

</div>

When julia used with multiple files and VS Code. What are options to render plots, doc, formulas? Basically just some sort of renderer like Notebook Viewer? For many years and currently I use my own reporting - basical…

---

## [Loading a library which depends on another library](https://discourse.julialang.org/t/loading-a-library-which-depends-on-another-library/131922)

<div class="topic-metadata">

**Author:** [@Chrysoberyl](https://discourse.julialang.org/u/Chrysoberyl)\
**Replies:** 2\
**Last updated:** [August 29, 2025, 12:23pm UTC](https://discourse.julialang.org/t/loading-a-library-which-depends-on-another-library/131922 "2025-08-29T12:23:09Z")

</div>

I have a project that is a mixture between Julia and Lean. The Lean part builds a dynamic library at .lake/build/lib/libPlaceholder.{dylib,so}, which in turn depends on the system Lean installation at ~/.elan/toolchains/…

---

## [Large execution time jumps](https://discourse.julialang.org/t/large-execution-time-jumps/131924)

<div class="topic-metadata">

**Author:** [@harri37](https://discourse.julialang.org/u/harri37)\
**Replies:** 2\
**Last updated:** [August 29, 2025, 9:26am UTC](https://discourse.julialang.org/t/large-execution-time-jumps/131924 "2025-08-29T09:26:36Z")

</div>

Hello everyone, I am working on building a computer algebra library in Julia and have encountered some strange behavior in how the execution time increases when I multiply polynomials. Essentially the code will execute…

---

## [Adding rows to data frame](https://discourse.julialang.org/t/adding-rows-to-data-frame/131925)

<div class="topic-metadata">

**Author:** [@SergeantMike](https://discourse.julialang.org/u/SergeantMike)\
**Replies:** 2\
**Last updated:** [August 29, 2025, 1:37am UTC](https://discourse.julialang.org/t/adding-rows-to-data-frame/131925 "2025-08-29T01:37:47Z")

</div>

I have a dataset that looks like this: Elapsed Days Insects Collected on that day 1 0 2 3 4 25 5 21 6 14 8 2 and I have a second dataset that is similar but is missing different days Elapsed Da…

---

## [Using Reactant with Lux and Enzyme to speed up training in physics context](https://discourse.julialang.org/t/using-reactant-with-lux-and-enzyme-to-speed-up-training-in-physics-context/131898)

<div class="topic-metadata">

**Author:** [@dameka](https://discourse.julialang.org/u/dameka)\
**Replies:** 16\
**Last updated:** [August 28, 2025, 8:56pm UTC](https://discourse.julialang.org/t/using-reactant-with-lux-and-enzyme-to-speed-up-training-in-physics-context/131898 "2025-08-28T20:56:28Z")

</div>

I am training a neural network in a physical context on observables; crucially, the network is producing values which are passed through some physics calculations before being compared to the training data. My code works…

---

## [What is the partial order used for multiple dispatch?](https://discourse.julialang.org/t/what-is-the-partial-order-used-for-multiple-dispatch/131911)

<div class="topic-metadata">

**Author:** [@rveltz](https://discourse.julialang.org/u/rveltz)\
**Replies:** 5\
**Last updated:** [August 28, 2025, 8:14pm UTC](https://discourse.julialang.org/t/what-is-the-partial-order-used-for-multiple-dispatch/131911 "2025-08-28T20:14:35Z")

</div>

In the docs, one can find that a paragraph on multiple dispatch but the dispatching algorithm is not described. My question is: given two tuples args1, args2 of arguments (or types), what is the partial order \< which is…

---

## [Cursed Custom Infix Operators](https://discourse.julialang.org/t/cursed-custom-infix-operators/131915)

<div class="topic-metadata">

**Author:** [@mrufsvold](https://discourse.julialang.org/u/mrufsvold)\
**Replies:** 2\
**Last updated:** [August 28, 2025, 4:44pm UTC](https://discourse.julialang.org/t/cursed-custom-infix-operators/131915 "2025-08-28T16:44:32Z")

</div>

Reading this StackExchange page on custom infix operators got me thinking about Julia’s special casing for infix operators and if there was any way to get that kind of expressiveness. Regular macros won’t work since you …

---

## [Which files to backup in .julia?](https://discourse.julialang.org/t/which-files-to-backup-in-julia/131906)

<div class="topic-metadata">

**Author:** [@hadrien.theveneau](https://discourse.julialang.org/u/hadrien.theveneau)\
**Replies:** 6\
**Last updated:** [August 28, 2025, 4:00pm UTC](https://discourse.julialang.org/t/which-files-to-backup-in-julia/131906 "2025-08-28T16:00:36Z")

</div>

Hi everyone, I regularly backup my WSL2 home directory, and I realized that the .julia folder is rather big. Is there any parts of this folder which I can skip ? Many thanks, Have a nice day, P.S: Here the folder siz…

---

## [Slow compilation with SecondOrderODEProblem](https://discourse.julialang.org/t/slow-compilation-with-secondorderodeproblem/131749)

<div class="topic-metadata">

**Author:** [@sijo](https://discourse.julialang.org/u/sijo)\
**Replies:** 3\
**Last updated:** [August 28, 2025, 1:55pm UTC](https://discourse.julialang.org/t/slow-compilation-with-secondorderodeproblem/131749 "2025-08-28T13:55:37Z")

</div>

Is the following expected? (DifferentialEquations 7.16 in Julia 1.11.6) using DifferentialEquations function OneDimSpring2!(ddu, du, u, p, t) ddu\[1\] = 1.0 + 1.0/u\[1\]^2 end du0 = \[0.0\] u0 = \[2.0\] tspan = (0.0, 50.0…

---

## [Will my variable be modified in a \`do\` block? Very subtle to anticipate](https://discourse.julialang.org/t/will-my-variable-be-modified-in-a-do-block-very-subtle-to-anticipate/131124)

<div class="topic-metadata">

**Author:** [@WalterMadelim](https://discourse.julialang.org/u/WalterMadelim)\
**Replies:** 13\
**Last updated:** [July 28, 2025, 11:28am UTC](https://discourse.julialang.org/t/will-my-variable-be-modified-in-a-do-block-very-subtle-to-anticipate/131124 "2025-07-28T11:28:09Z")

</div>

I notice this difference julia\> Threads.nthreads() 4 julia\> my\_lock = Threads.ReentrantLock() ReentrantLock(nothing, 0x00000000, 0x00, Base.GenericCondition{Base.Threads.SpinLock}(Base.IntrusiveLinkedList{Task}(nothing…

---

## [Can you find where this asynchronous program get stuck at?](https://discourse.julialang.org/t/can-you-find-where-this-asynchronous-program-get-stuck-at/131907)

<div class="topic-metadata">

**Author:** [@WalterMadelim](https://discourse.julialang.org/u/WalterMadelim)\
**Replies:** 2\
**Last updated:** [August 28, 2025, 9:45am UTC](https://discourse.julialang.org/t/can-you-find-where-this-asynchronous-program-get-stuck-at/131907 "2025-08-28T09:45:13Z")

</div>

I wrote a weird test function function test() function taskbody(k, x, j, e) sleep(0.5 \* j) println("At k = $k, j = $j, x = $x") @lock mylock i+=1 notify(e) end my\_lock = Threa…

---

## [Performance of \`exp(A)\` for 9x9 anti-Hermitian matrix: Julia vs. PyTorch vs. MATLAB (CPU & GPU)](https://discourse.julialang.org/t/performance-of-exp-a-for-9x9-anti-hermitian-matrix-julia-vs-pytorch-vs-matlab-cpu-gpu/131696)

<div class="topic-metadata">

**Author:** [@draftman9](https://discourse.julialang.org/u/draftman9)\
**Replies:** 29\
**Last updated:** [August 28, 2025, 2:25am UTC](https://discourse.julialang.org/t/performance-of-exp-a-for-9x9-anti-hermitian-matrix-julia-vs-pytorch-vs-matlab-cpu-gpu/131696 "2025-08-28T02:25:07Z")

</div>

Hi everyone, I’m a Ph.D. student in physics. A core part of my research involves simulating the time evolution of quantum systems, which boils down to frequently calculating the matrix exponential U = exp(A). For these…

---

## [Poll: What do you use: Distributed or MPI?](https://discourse.julialang.org/t/poll-what-do-you-use-distributed-or-mpi/131741)

<div class="topic-metadata">

**Author:** [@linwaytin](https://discourse.julialang.org/u/linwaytin)\
**Replies:** 14\
**Last updated:** [August 27, 2025, 10:57pm UTC](https://discourse.julialang.org/t/poll-what-do-you-use-distributed-or-mpi/131741 "2025-08-27T22:57:51Z")

</div>

Julia’s default multi-processing system, Distributed, is based on a different paradigm than the de facto standard MPI in HPC. I’m really wondering the numbers of people using the two different types of distributed compu…

---

## [Latex fonts on axis and labels in Makie](https://discourse.julialang.org/t/latex-fonts-on-axis-and-labels-in-makie/131887)

<div class="topic-metadata">

**Author:** [@tduretz](https://discourse.julialang.org/u/tduretz)\
**Replies:** 7\
**Last updated:** [August 27, 2025, 3:33pm UTC](https://discourse.julialang.org/t/latex-fonts-on-axis-and-labels-in-makie/131887 "2025-08-27T15:33:09Z")

</div>

I would like to use LaTeX fonts for every text of a Makie figure. It’s easy to apply them to labels as LaTeXStrings can be used. For other texts, in particular axis tick labels, it a bit less trivial. I was once told …

---

## [Challenges with installing Julia on Windows](https://discourse.julialang.org/t/challenges-with-installing-julia-on-windows/128133)

<div class="topic-metadata">

**Author:** [@uwestoehr](https://discourse.julialang.org/u/uwestoehr)\
**Replies:** 19\
**Last updated:** [August 27, 2025, 11:32am UTC](https://discourse.julialang.org/t/challenges-with-installing-julia-on-windows/128133 "2025-08-27T11:32:20Z")

</div>

3 issues from my side: the most severe is that you cannot install Julia for all users of a computer. To be able to use Julia with all its features (e.g. PackageCompiler), the julia.exe must be in the PATH environment …

---

## [Weird error when trying to use \`≔\` (\\coloneq) as infix operator](https://discourse.julialang.org/t/weird-error-when-trying-to-use-coloneq-as-infix-operator/21578)

<div class="topic-metadata">

**Author:** [@simeonschaub](https://discourse.julialang.org/u/simeonschaub)\
**Replies:** 2\
**Last updated:** [August 27, 2025, 11:16am UTC](https://discourse.julialang.org/t/weird-error-when-trying-to-use-coloneq-as-infix-operator/21578 "2025-08-27T11:16:53Z")

</div>

When overloading ≔ like this: julia\> ≔(a, b) = a==b ≔ (generic function with 1 method) the following works just fine: julia\> ≔(3,2) false But I get a weird error when trying to use it as an infix-operator: julia\> 2≔…

---

## [Will \`@info\` corrupt \`Threads.@threads for\`?](https://discourse.julialang.org/t/will-info-corrupt-threads-threads-for/131805)

<div class="topic-metadata">

**Author:** [@WalterMadelim](https://discourse.julialang.org/u/WalterMadelim)\
**Replies:** 18\
**Last updated:** [August 26, 2025, 3:18pm UTC](https://discourse.julialang.org/t/will-info-corrupt-threads-threads-for/131805 "2025-08-26T15:18:53Z")

</div>

My configuration is julia\> Threads.nthreads() 4 julia\> Threads.nthreads(:default) 4 I have a function function parallel\_CG!(B, θ, β, μ, ν) for ite = ... ... for ba = ... sub\_j\_vec = .…

---

## [Simulating Continuous Time Models in Julia](https://discourse.julialang.org/t/simulating-continuous-time-models-in-julia/131846)

<div class="topic-metadata">

**Author:** [@GregCamp](https://discourse.julialang.org/u/GregCamp)\
**Replies:** 5\
**Last updated:** [August 26, 2025, 6:40pm UTC](https://discourse.julialang.org/t/simulating-continuous-time-models-in-julia/131846 "2025-08-26T18:40:40Z")

</div>

I’m interested in simulating a relatively simple continuous-time model in Julia. The model is a variation of the Diamond-Mortensen-Pissarides (DMP) framework with the following elements: Agents are either employed at …

---

## [How to discretize a PDE with a Moving Boundary? (a.k.a Stefan Problem, a.k.a Variable Boundary)](https://discourse.julialang.org/t/how-to-discretize-a-pde-with-a-moving-boundary-a-k-a-stefan-problem-a-k-a-variable-boundary/123687)

<div class="topic-metadata">

**Author:** [@Jax\_Xu](https://discourse.julialang.org/u/Jax_Xu)\
**Replies:** 6\
**Last updated:** [August 26, 2025, 9:12am UTC](https://discourse.julialang.org/t/how-to-discretize-a-pde-with-a-moving-boundary-a-k-a-stefan-problem-a-k-a-variable-boundary/123687 "2025-08-26T09:12:30Z")

</div>

Hi Community! I need your expertise :sob:! I am solving a 1D diffusion equation with a moving boundary. The physical background is the reaction of gas with a solid particle, where the gas diffuses through the product lay…

---

## [Lux + Enzyme naively applying model seems to cause runtime activity error](https://discourse.julialang.org/t/lux-enzyme-naively-applying-model-seems-to-cause-runtime-activity-error/131531)

<div class="topic-metadata">

**Author:** [@r0uv3n](https://discourse.julialang.org/u/r0uv3n)\
**Replies:** 23\
**Last updated:** [August 25, 2025, 10:56am UTC](https://discourse.julialang.org/t/lux-enzyme-naively-applying-model-seems-to-cause-runtime-activity-error/131531 "2025-08-25T10:56:54Z")

</div>

Consider the simple setup using Lux, LinearAlgebra import Optimization, Random, Enzyme, ComponentArrays model = Chain( Dense(2 =\> 16, Lux.tanh), Dense(16, 1), ) parameters, states = Lux.setup(Random.Xoshiro(42…

---

## [Will juliac solve the relocatabiliy issue?](https://discourse.julialang.org/t/will-juliac-solve-the-relocatabiliy-issue/131780)

<div class="topic-metadata">

**Author:** [@ohmsweetohm1](https://discourse.julialang.org/u/ohmsweetohm1)\
**Replies:** 36\
**Last updated:** [August 25, 2025, 7:09pm UTC](https://discourse.julialang.org/t/will-juliac-solve-the-relocatabiliy-issue/131780 "2025-08-25T19:09:06Z")

</div>

I have found that generating an app using PackageCompiler.jl only works for kind of academic examples since any dependency potentially breaks relocatabiliy. Our solution to this is to actually use docker images and bundl…

---

## [Suddenly can no longer run test (due to breaking \`\]add Package\` midway?)](https://discourse.julialang.org/t/suddenly-can-no-longer-run-test-due-to-breaking-add-package-midway/131813)

<div class="topic-metadata">

**Author:** [@Torkel](https://discourse.julialang.org/u/Torkel)\
**Replies:** 8\
**Last updated:** [August 25, 2025, 12:58pm UTC](https://discourse.julialang.org/t/suddenly-can-no-longer-run-test-due-to-breaking-add-package-midway/131813 "2025-08-25T12:58:54Z")

</div>

I am developing a package, however, suddently, where I try to run \]test I get a crash. A potential reason is that I pasted some code into the REPL which contained a using ... statement for a package I did not want to a…

---

## [Running out of disk space on HPC without really doing anything unusual](https://discourse.julialang.org/t/running-out-of-disk-space-on-hpc-without-really-doing-anything-unusual/131812)

<div class="topic-metadata">

**Author:** [@Torkel](https://discourse.julialang.org/u/Torkel)\
**Replies:** 3\
**Last updated:** [August 25, 2025, 9:53am UTC](https://discourse.julialang.org/t/running-out-of-disk-space-on-hpc-without-really-doing-anything-unusual/131812 "2025-08-25T09:53:46Z")

</div>

I have some workflows that I am running on an HPC, and I have suddenly run out of space, preventing me from actually doing anything. The actual scripts and stuff I have created corresponds to 2 MB, and I have reached the…

[Previous page](https://discourse.julialang.org/c/usage/6.md?page=42)

[Next page](https://discourse.julialang.org/c/usage/6.md?page=44)