# Latest

**URL:** https://discourse.julialang.org/latest.md?page=528

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

**Page:** 529

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## [How to correctly update a package?](https://discourse.julialang.org/t/how-to-correctly-update-a-package/107730)

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**Author:** [@jiang\_ming\_zhang](https://discourse.julialang.org/u/jiang_ming_zhang)\
**Replies:** 2\
**Last updated:** [December 17, 2023, 1:07pm UTC](https://discourse.julialang.org/t/how-to-correctly-update-a-package/107730 "2023-12-17T13:07:38Z")

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I had a directory downloaded from Github. Previously, I can run the example codes in the directory. But yesterday, I noticed that they had a latest version of the package. So I updated the package julia\> using Pkg jul…

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## [Interactive ABM plot with agents and GLMakie](https://discourse.julialang.org/t/interactive-abm-plot-with-agents-and-glmakie/98913)

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**Author:** [@sea\_slug](https://discourse.julialang.org/u/sea_slug)\
**Replies:** 3\
**Last updated:** [December 17, 2023, 11:26am UTC](https://discourse.julialang.org/t/interactive-abm-plot-with-agents-and-glmakie/98913 "2023-12-17T11:26:19Z")

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I am trying to produce an interactive plot of an agent based model using GLMakie. I Have done this before no problem (a few months ago), but now when I run the code it just produces a static plot in VSCode. I have been …

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## ['\_' as an argument in function definition](https://discourse.julialang.org/t/as-an-argument-in-function-definition/107708)

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**Author:** [@jiang\_ming\_zhang](https://discourse.julialang.org/u/jiang_ming_zhang)\
**Replies:** 8\
**Last updated:** [December 17, 2023, 11:06am UTC](https://discourse.julialang.org/t/as-an-argument-in-function-definition/107708 "2023-12-17T11:06:48Z")

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function myfun(x, i, val, \_) x\[i\]+ = val end What does the underscore ‘\_’ mean here?

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## [The CFP deadline for mini-symposia has been extended until next week on Tuesday December 19th](https://discourse.julialang.org/t/the-cfp-deadline-for-mini-symposia-has-been-extended-until-next-week-on-tuesday-december-19th/107715)

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**Author:** [@Steven\_Kell](https://discourse.julialang.org/u/Steven_Kell)\
**Replies:** 0\
**Last updated:** [December 16, 2023, 8:23pm UTC](https://discourse.julialang.org/t/the-cfp-deadline-for-mini-symposia-has-been-extended-until-next-week-on-tuesday-december-19th/107715 "2023-12-16T20:23:19Z")

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The CFP deadline for mini-symposia has been extended until Tuesday, December 19th next week.

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## [How to update a package?](https://discourse.julialang.org/t/how-to-update-a-package/107727)

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**Author:** [@jiang\_ming\_zhang](https://discourse.julialang.org/u/jiang_ming_zhang)\
**Replies:** 1\
**Last updated:** [December 17, 2023, 7:35am UTC](https://discourse.julialang.org/t/how-to-update-a-package/107727 "2023-12-17T07:35:12Z")

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julia\> Pkg.update("thepackage") ERROR: UndefVarError: \`Pkg\` not defined Stacktrace: \[1\] top-level scope @ REPL\[38\]:1 What is the correct way?

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## [Sparse A\\B](https://discourse.julialang.org/t/sparse-a-b/107725)

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**Author:** [@tbeason](https://discourse.julialang.org/u/tbeason)\
**Replies:** 2\
**Last updated:** [December 17, 2023, 4:10am UTC](https://discourse.julialang.org/t/sparse-a-b/107725 "2023-12-17T04:10:11Z")

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What is the best way to solve A\\B where A and B are sparse, and where the result is also known to be sparse? Right now it seems I have to do sparse(A \\ Matrix(B)).

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## [Get the structure of an arithmetic expression](https://discourse.julialang.org/t/get-the-structure-of-an-arithmetic-expression/107712)

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**Author:** [@\_stla](https://discourse.julialang.org/u/_stla)\
**Replies:** 8\
**Last updated:** [December 17, 2023, 3:38am UTC](https://discourse.julialang.org/t/get-the-structure-of-an-arithmetic-expression/107712 "2023-12-17T03:38:46Z")

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Hello, Given an arithmetic expression, for example x + y/z, I want to decompose it to something like +(x, /(y, z). Is it possible with Julia? I thought this was the result of :(x + y/z) but no. The reason is that I hav…

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## [ModelingToolkit and normalize()](https://discourse.julialang.org/t/modelingtoolkit-and-normalize/107349)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 12\
**Last updated:** [December 17, 2023, 3:08am UTC](https://discourse.julialang.org/t/modelingtoolkit-and-normalize/107349 "2023-12-17T03:08:20Z")

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The following code fails: using ModelingToolkit, OrdinaryDiffEq, PyPlot, LinearAlgebra G\_EARTH = Float64\[0.0, 0.0, -9.81\] # gravitational acceleration # model @parameters mass=1.0 c\_spring=50.0 damping=0.5 l0=10.0…

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## [Understanding type Ref{T}](https://discourse.julialang.org/t/understanding-type-ref-t/107711)

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**Author:** [@hlbnet](https://discourse.julialang.org/u/hlbnet)\
**Replies:** 9\
**Last updated:** [December 17, 2023, 2:13am UTC](https://discourse.julialang.org/t/understanding-type-ref-t/107711 "2023-12-17T02:13:07Z")

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Hello, I am reading the documentation of the Ref type template: C Interface · The Julia Language Unfortunately, it doesn’t make sense to me. There are a few examples of use of the Ref type, but I hardly see any value o…

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## [Question About Intercept & Link Function in Bayesian Logistic Regression](https://discourse.julialang.org/t/question-about-intercept-link-function-in-bayesian-logistic-regression/105596)

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**Author:** [@mthelm85](https://discourse.julialang.org/u/mthelm85)\
**Replies:** 7\
**Last updated:** [December 17, 2023, 1:28am UTC](https://discourse.julialang.org/t/question-about-intercept-link-function-in-bayesian-logistic-regression/105596 "2023-12-17T01:28:15Z")

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Assume the following: I repeat a game over and over in which I roll a die a number of times. If I roll a 6 on any of the trials, I win. Otherwise, I lose. I want to model how the probability of winning this game changes …

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## [What is the role of this word?](https://discourse.julialang.org/t/what-is-the-role-of-this-word/107704)

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**Author:** [@hlbnet](https://discourse.julialang.org/u/hlbnet)\
**Replies:** 2\
**Last updated:** [December 16, 2023, 9:49pm UTC](https://discourse.julialang.org/t/what-is-the-role-of-this-word/107704 "2023-12-16T21:49:11Z")

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Hello, I am very new to Julia. Browsing Julia code implementation, I can see the following construct: """ Some comments here ... """ Foo ... My question is about this single word, here Foo, that is alone on a lin…

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## [CUDA.jl - MethodError: no method matching CUDA.CuArray](https://discourse.julialang.org/t/cuda-jl-methoderror-no-method-matching-cuda-cuarray/107717)

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**Author:** [@maria96](https://discourse.julialang.org/u/maria96)\
**Replies:** 0\
**Last updated:** [December 16, 2023, 9:03pm UTC](https://discourse.julialang.org/t/cuda-jl-methoderror-no-method-matching-cuda-cuarray/107717 "2023-12-16T21:03:36Z")

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I’m training a Neural Network using NeuralEstimators.jl in julia, and I’m submitting my code in my slurm high performance computer. For some reason, it is not working now using GPUs (it was working before) but it is work…

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## [Solving a system of matrix differential equations using DifferentialEquations.jl](https://discourse.julialang.org/t/solving-a-system-of-matrix-differential-equations-using-differentialequations-jl/107663)

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**Author:** [@Aleksandr\_Mikheev](https://discourse.julialang.org/u/Aleksandr_Mikheev)\
**Replies:** 5\
**Last updated:** [December 16, 2023, 7:56pm UTC](https://discourse.julialang.org/t/solving-a-system-of-matrix-differential-equations-using-differentialequations-jl/107663 "2023-12-16T19:56:11Z")

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How shall I initialize my initial condition for the system of matrix differential equations using DifferentialEquations.jl? As a simple example, suppose I want to solve the following trivial system of equations: functio…

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## [Chebyshev Transform using FFTW and FastTransforms.jl Speed](https://discourse.julialang.org/t/chebyshev-transform-using-fftw-and-fasttransforms-jl-speed/107387)

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**Author:** [@erny123](https://discourse.julialang.org/u/erny123)\
**Replies:** 6\
**Last updated:** [December 16, 2023, 6:18pm UTC](https://discourse.julialang.org/t/chebyshev-transform-using-fftw-and-fasttransforms-jl-speed/107387 "2023-12-16T18:18:38Z")

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I’m looking into spectral methods for some PDEs. For the discrete Chebyshev Transform, it is basically a discrete cosine transform: I’ve looked at FastTransforms.jl as they have a Chebyshev Transform which can be used…

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## [The colon punctuation: Why doesn't 5:1 return \[5, 4, 3, 2, 1\]?](https://discourse.julialang.org/t/the-colon-punctuation-why-doesnt-5-1-return-5-4-3-2-1/107676)

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**Author:** [@Tetrakai](https://discourse.julialang.org/u/Tetrakai)\
**Replies:** 8\
**Last updated:** [December 16, 2023, 6:04pm UTC](https://discourse.julialang.org/t/the-colon-punctuation-why-doesnt-5-1-return-5-4-3-2-1/107676 "2023-12-16T18:04:19Z")

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I got surprised by this: julia\> 1:5 # Expected 1:5 julia\> 5:1 # Unexpected 5:4 julia\> collect(1:5) # Expected 5-element Vector{Int64}: 1 2 3 4 5 julia\> collect(5:1) # Doubly Unexpected Int64\[\] julia\> collect(5:…

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## [Why function names starting with '\_'?](https://discourse.julialang.org/t/why-function-names-starting-with/107696)

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**Author:** [@jiang\_ming\_zhang](https://discourse.julialang.org/u/jiang_ming_zhang)\
**Replies:** 5\
**Last updated:** [December 16, 2023, 5:14pm UTC](https://discourse.julialang.org/t/why-function-names-starting-with/107696 "2023-12-16T17:14:29Z")

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I see many functions named like ‘\_my\_fun1’ in some package. What is the purpose of such naming? I guess it is a standard practice in programing, right?

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## [Impossible to add functional packages in Julia v1.9: Plots, Interact, WebIO](https://discourse.julialang.org/t/impossible-to-add-functional-packages-in-julia-v1-9-plots-interact-webio/107699)

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**Author:** [@Constant31](https://discourse.julialang.org/u/Constant31)\
**Replies:** 6\
**Last updated:** [December 16, 2023, 4:21pm UTC](https://discourse.julialang.org/t/impossible-to-add-functional-packages-in-julia-v1-9-plots-interact-webio/107699 "2023-12-16T16:21:19Z")

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Hello everybody, I’m new on Julia Discourse, used Julia from version 0.6.4, 1.0 and after 1.6.x LTS I tried to jump to one of the last stable versions, so I installed a portable version 1.9. My goal was essentially to…

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## [Integrate Julia scripts into NI Labview](https://discourse.julialang.org/t/integrate-julia-scripts-into-ni-labview/42281)

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**Author:** [@Jonathan\_Israel\_Hern](https://discourse.julialang.org/u/Jonathan_Israel_Hern)\
**Replies:** 10\
**Last updated:** [December 16, 2023, 12:36pm UTC](https://discourse.julialang.org/t/integrate-julia-scripts-into-ni-labview/42281 "2023-12-16T12:36:04Z")

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Hello, how about everyone, my most sincere and cordial greetings to all who read this post. I am a fairly new user and amazed at how great it is to use Julia as an alternative to other languages. My question is a bit s…

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## [My manual Fixed/Random Effects Model perform weirdly](https://discourse.julialang.org/t/my-manual-fixed-random-effects-model-perform-weirdly/107705)

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**Author:** [@Wooheon](https://discourse.julialang.org/u/Wooheon)\
**Replies:** 0\
**Last updated:** [December 16, 2023, 10:13am UTC](https://discourse.julialang.org/t/my-manual-fixed-random-effects-model-perform-weirdly/107705 "2023-12-16T10:13:53Z")

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Hi, I am trying to make manual code for the Fixed/Random Effects model estimation to understand how the process works. However, my manual codes for both models never reject the null for the fake data set. I want to as…

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## [Not being able to update](https://discourse.julialang.org/t/not-being-able-to-update/107703)

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**Author:** [@photor](https://discourse.julialang.org/u/photor)\
**Replies:** 0\
**Last updated:** [December 16, 2023, 9:34am UTC](https://discourse.julialang.org/t/not-being-able-to-update/107703 "2023-12-16T09:34:36Z")

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What’s wrong here? Thanks. (@v1.7) pkg\> up IntelVectorMath Updating registry at \`C:\\Users\\ytian\\.julia\\registries\\General.toml\` ┌ Warning: could not download https://pkg.julialang.org/registries │ exception = HTTP…

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## [Using print on pi produces π rather than 3.141592653589793](https://discourse.julialang.org/t/using-print-on-pi-produces-rather-than-3-141592653589793/107682)

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**Author:** [@KevinMoerman](https://discourse.julialang.org/u/KevinMoerman)\
**Replies:** 6\
**Last updated:** [December 16, 2023, 12:48am UTC](https://discourse.julialang.org/t/using-print-on-pi-produces-rather-than-3-141592653589793/107682 "2023-12-16T00:48:48Z")

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Is it normal that Julia’s print prints constants as their character or name rather than an interpretation of the numerical value? For instance julia\> print(pi) π Multiply it by something though, e.g. 1, forces the int…

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## [Why does this really simple linear SDE diverge?](https://discourse.julialang.org/t/why-does-this-really-simple-linear-sde-diverge/107640)

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**Author:** [@George\_Stepaniants](https://discourse.julialang.org/u/George_Stepaniants)\
**Replies:** 5\
**Last updated:** [December 16, 2023, 12:15am UTC](https://discourse.julialang.org/t/why-does-this-really-simple-linear-sde-diverge/107640 "2023-12-16T00:15:12Z")

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using DifferentialEquations using LinearAlgebra N = 5 conn = -Matrix{Float64}(I, N, N) sigma = Matrix{Float64}(I, N, N) f(v, p, t) = conn \* v g(v, p, t) = sigma Nt = 200 T = 100.0 # measured in seconds prob = SDEProbl…

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## [Updating the same plot window with multiple panes in a loop](https://discourse.julialang.org/t/updating-the-same-plot-window-with-multiple-panes-in-a-loop/107690)

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**Author:** [@eveningsilverfox](https://discourse.julialang.org/u/eveningsilverfox)\
**Replies:** 0\
**Last updated:** [December 15, 2023, 11:20pm UTC](https://discourse.julialang.org/t/updating-the-same-plot-window-with-multiple-panes-in-a-loop/107690 "2023-12-15T23:20:31Z")

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I am trying to update the same plot window in loop, with the window having multiple (in this case, two is sufficient) panes. But this code doesn’t update the window. How do I go about doing this? EDIT: It is fine even …

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## [Package for matrix polynomials](https://discourse.julialang.org/t/package-for-matrix-polynomials/107687)

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**Author:** [@fph](https://discourse.julialang.org/u/fph)\
**Replies:** 2\
**Last updated:** [December 15, 2023, 10:23pm UTC](https://discourse.julialang.org/t/package-for-matrix-polynomials/107687 "2023-12-15T22:23:22Z")

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What package do you recommend to work with matrix polynomials, i.e., expressions of the form A(x) = A\_0 + A\_1 x + \\dots + A\_d x^d? I will use mainly the coefficients to do linear algebra, so I am interested in a package…

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## [Benchmarking Symbolics.jl against SymEngine.jl](https://discourse.julialang.org/t/benchmarking-symbolics-jl-against-symengine-jl/103744)

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**Author:** [@certik](https://discourse.julialang.org/u/certik)\
**Replies:** 8\
**Last updated:** [December 15, 2023, 9:47pm UTC](https://discourse.julialang.org/t/benchmarking-symbolics-jl-against-symengine-jl/103744 "2023-12-15T21:47:26Z")

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I finally found time to benchmark the Symbolics.jl against SymEngine.jl. Here are the results: Am I doing anything wrong with how I run them? So far on my computer Symbolics.jl seems slower. I want to make sure that I…

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## [Regularized horseshoe prior](https://discourse.julialang.org/t/regularized-horseshoe-prior/71599)

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**Author:** [@rikh](https://discourse.julialang.org/u/rikh)\
**Replies:** 10\
**Last updated:** [December 15, 2023, 8:13pm UTC](https://discourse.julialang.org/t/regularized-horseshoe-prior/71599 "2023-12-15T20:13:10Z")

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Anyone here who has some working Turing.jl (or Soss.jl) code for the regularized horseshoe prior (e.g., Piironen, 2007)? The horseshoe prior is a regularization technique (reduces the chance of overfitting) for when the…

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## [Executing code blocks with REPL workspace](https://discourse.julialang.org/t/executing-code-blocks-with-repl-workspace/107572)

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**Author:** [@kealme](https://discourse.julialang.org/u/kealme)\
**Replies:** 13\
**Last updated:** [December 15, 2023, 6:54pm UTC](https://discourse.julialang.org/t/executing-code-blocks-with-repl-workspace/107572 "2023-12-15T18:54:14Z")

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Hi, I have a very basic question about Julia: I’ve written a function in julia and im trying to debug the code. I can mark a block of code and execute it using Shift+Enter. However, when executing the code like this, t…

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## [How to build a matrix where each element is a vector](https://discourse.julialang.org/t/how-to-build-a-matrix-where-each-element-is-a-vector/107674)

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**Author:** [@PeX](https://discourse.julialang.org/u/PeX)\
**Replies:** 4\
**Last updated:** [December 15, 2023, 5:02pm UTC](https://discourse.julialang.org/t/how-to-build-a-matrix-where-each-element-is-a-vector/107674 "2023-12-15T17:02:49Z")

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Hi all, I’m looking for the best way to construct a matrix where each element is an actual vector. More specifically, if I have: fs = 10 # Sampling Frequnecy \[Hz\] 𝑓 = 1e-3 # Forcing frequency \[Hz\] t\_end = 10^4 t = col…

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## [What is the right way to store/record the results of this nested simulation?](https://discourse.julialang.org/t/what-is-the-right-way-to-store-record-the-results-of-this-nested-simulation/107639)

<div class="topic-metadata">

**Author:** [@Tetrakai](https://discourse.julialang.org/u/Tetrakai)\
**Replies:** 8\
**Last updated:** [December 15, 2023, 4:25pm UTC](https://discourse.julialang.org/t/what-is-the-right-way-to-store-record-the-results-of-this-nested-simulation/107639 "2023-12-15T16:25:49Z")

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I wrote this after seeing the responses to my last question. From the responses I can tell my problem was not understood. What this simulation does is play a rudimentary “game” between pairs of two teams once per “week…

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## [Documentation rendered fine in GitHub but not on juliahub](https://discourse.julialang.org/t/documentation-rendered-fine-in-github-but-not-on-juliahub/107668)

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**Author:** [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Replies:** 4\
**Last updated:** [December 15, 2023, 4:02pm UTC](https://discourse.julialang.org/t/documentation-rendered-fine-in-github-but-not-on-juliahub/107668 "2023-12-15T16:02:01Z")

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Hello, the documentation of one of my packages (BetaML) is rendered fine in GitHub pages, but has several errors in JuliaHub: What could be the cause ? (I would also have another question, why to replicate documenta…

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