# Latest

**URL:** https://discourse.julialang.org/latest.md?page=585

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

**Page:** 586

---

## [Is it possible/advisable to have multiline error message?](https://discourse.julialang.org/t/is-it-possible-advisable-to-have-multiline-error-message/104513)

<div class="topic-metadata">

**Author:** [@David\_Sagan](https://discourse.julialang.org/u/David_Sagan)\
**Replies:** 1\
**Last updated:** [October 2, 2023, 9:44pm UTC](https://discourse.julialang.org/t/is-it-possible-advisable-to-have-multiline-error-message/104513 "2023-10-02T21:44:31Z")

</div>

throw shows a multiline (has \\n characters) string as a single line. Example: julia\> throw("a\\n b") ERROR: "a\\n b" Stacktrace: \[1\] top-level scope @ REPL\[3\]:1 Is it possible to have a multiline error message? Is th…

---

## [Standardize all columns of DataFrame](https://discourse.julialang.org/t/standardize-all-columns-of-dataframe/77772)

<div class="topic-metadata">

**Author:** [@markmbaum](https://discourse.julialang.org/u/markmbaum)\
**Replies:** 9\
**Last updated:** [October 2, 2023, 8:07pm UTC](https://discourse.julialang.org/t/standardize-all-columns-of-dataframe/77772 "2023-10-02T20:07:03Z")

</div>

Surely this is answered somewhere, but what is the easiest way to standardize all columns of a DataFrame? There are a bunch of methods in pandas to do it, or you can just df = (df - df.mean())/df.std() how to do the sa…

---

## [PackageCompiler @ccallable for julia function that take String's as arguments](https://discourse.julialang.org/t/packagecompiler-ccallable-for-julia-function-that-take-strings-as-arguments/104507)

<div class="topic-metadata">

**Author:** [@Allan\_Baker](https://discourse.julialang.org/u/Allan_Baker)\
**Replies:** 3\
**Last updated:** [October 2, 2023, 7:09pm UTC](https://discourse.julialang.org/t/packagecompiler-ccallable-for-julia-function-that-take-strings-as-arguments/104507 "2023-10-02T19:09:39Z")

</div>

I have a C/C++ based simulation. I want to package Julia Code that loads a custom data-base type object and does some fast lookups and quick calculations so it is accessible to C. So I’m trying to set things up to make…

---

## [Postdoc and PhD positions in molecular dynamics lab in Cambridge, UK](https://discourse.julialang.org/t/postdoc-and-phd-positions-in-molecular-dynamics-lab-in-cambridge-uk/104508)

<div class="topic-metadata">

**Author:** [@jgreener64](https://discourse.julialang.org/u/jgreener64)\
**Replies:** 0\
**Last updated:** [October 2, 2023, 6:00pm UTC](https://discourse.julialang.org/t/postdoc-and-phd-positions-in-molecular-dynamics-lab-in-cambridge-uk/104508 "2023-10-02T18:00:49Z")

</div>

I am starting a research group at the MRC Laboratory of Molecular Biology in Cambridge UK and have two positions to advertise. The lab will aim to develop a universal biomolecular force field for molecular simulation usi…

---

## [Are extension packages importable?](https://discourse.julialang.org/t/are-extension-packages-importable/92527)

<div class="topic-metadata">

**Author:** [@cjdoris](https://discourse.julialang.org/u/cjdoris)\
**Replies:** 26\
**Last updated:** [October 2, 2023, 5:42pm UTC](https://discourse.julialang.org/t/are-extension-packages-importable/92527 "2023-10-02T17:42:35Z")

</div>

The new extension packages functionality looks great! Code Loading · The Julia Language I get that its intended use is to provide Requires.jl-like functionality, i.e. to run some code when some other package is loaded, …

---

## [Interest in a meta interpolation package?](https://discourse.julialang.org/t/interest-in-a-meta-interpolation-package/104343)

<div class="topic-metadata">

**Author:** [@mkitti](https://discourse.julialang.org/u/mkitti)\
**Replies:** 2\
**Last updated:** [October 2, 2023, 4:19pm UTC](https://discourse.julialang.org/t/interest-in-a-meta-interpolation-package/104343 "2023-10-02T16:19:54Z")

</div>

I am currently the maintainer of Interpolations.jl. There are also many other interpolaton packages with different capabilities: https://juliamath.github.io/Interpolations.jl/stable/other\_packages/ With package extensi…

---

## [How to tell ModelingToolkit.jl which variables are parameters](https://discourse.julialang.org/t/how-to-tell-modelingtoolkit-jl-which-variables-are-parameters/104501)

<div class="topic-metadata">

**Author:** [@Lilith](https://discourse.julialang.org/u/Lilith)\
**Replies:** 4\
**Last updated:** [October 2, 2023, 4:11pm UTC](https://discourse.julialang.org/t/how-to-tell-modelingtoolkit-jl-which-variables-are-parameters/104501 "2023-10-02T16:11:07Z")

</div>

I have a Symbolics.Equation that I got from an external source. Now I want to use that equation in ModelingToolkit.jl, but I don’t know how to tell ModelingToolkit.jl which variables are parameters. For example, here I …

---

## [Is it wrong to call Julia interpreted?](https://discourse.julialang.org/t/is-it-wrong-to-call-julia-interpreted/104296)

<div class="topic-metadata">

**Author:** [@ninjaaron](https://discourse.julialang.org/u/ninjaaron)\
**Replies:** 104\
**Last updated:** [October 2, 2023, 9:36am UTC](https://discourse.julialang.org/t/is-it-wrong-to-call-julia-interpreted/104296 "2023-10-02T09:36:32Z")

</div>

@sdanisch and I are having it out in a GitHub issue about whether or not it is correct to call Julia an interpreted language. Julia is not an interpreted Language · Issue #7 · ninjaaron/administrative-scripting-with-juli…

---

## [Is it posible to make a 2D slider in Makie?](https://discourse.julialang.org/t/is-it-posible-to-make-a-2d-slider-in-makie/104349)

<div class="topic-metadata">

**Author:** [@Knud\_Sorensen](https://discourse.julialang.org/u/Knud_Sorensen)\
**Replies:** 2\
**Last updated:** [October 2, 2023, 2:50pm UTC](https://discourse.julialang.org/t/is-it-posible-to-make-a-2d-slider-in-makie/104349 "2023-10-02T14:50:02Z")

</div>

Is it possible to make a 2D slider ?? In the following code I would like to have a circle in a rectangle that I can drag around instead of 2 different sliders. How would you do that ? using GLMakie fig = Figure() sl\_…

---

## [Nonlinear expressions may contain only scalar expressions](https://discourse.julialang.org/t/nonlinear-expressions-may-contain-only-scalar-expressions/45147)

<div class="topic-metadata">

**Author:** [@zlq178](https://discourse.julialang.org/u/zlq178)\
**Replies:** 3\
**Last updated:** [October 2, 2023, 2:27pm UTC](https://discourse.julialang.org/t/nonlinear-expressions-may-contain-only-scalar-expressions/45147 "2023-10-02T14:27:51Z")

</div>

using JuMP,Gurobi n=4 PL=\[0.3;0.55;0;0\] model=Model(Gurobi.Optimizer) G=\[1.04209 -0.588235 -0.0 -0.453858;-0.588235 1.069 0 -0.480769;-0 0 0 0;-0.453858 -0.480769 0 0.934627\] Q=\[-8.24288 2.35294 3.66667 1.89107; …

---

## [Aliasing two structs and having them be subtypes of an abstract type?](https://discourse.julialang.org/t/aliasing-two-structs-and-having-them-be-subtypes-of-an-abstract-type/104410)

<div class="topic-metadata">

**Author:** [@linkz](https://discourse.julialang.org/u/linkz)\
**Replies:** 10\
**Last updated:** [October 2, 2023, 1:46pm UTC](https://discourse.julialang.org/t/aliasing-two-structs-and-having-them-be-subtypes-of-an-abstract-type/104410 "2023-10-02T13:46:10Z")

</div>

I am wondering if when I have two structs, say mutable struct A{a, b} str\_a::a str\_b::b end mutable struct B{a, b, c} str\_a::a str\_b::b str\_c::c end and I alias const A\_num = A{\<:Number} const B\_num = …

---

## [Combining \`eachindex\` and \`axes\`?](https://discourse.julialang.org/t/combining-eachindex-and-axes/104442)

<div class="topic-metadata">

**Author:** [@gdalle](https://discourse.julialang.org/u/gdalle)\
**Replies:** 2\
**Last updated:** [October 2, 2023, 1:28pm UTC](https://discourse.julialang.org/t/combining-eachindex-and-axes/104442 "2023-10-02T13:28:43Z")

</div>

One of the things I like about eachindex is that you can give it several arrays and it throws a DimensionMismatch if they have different sizes. I wonder if it would make sense to enable the same with axes(A, d), possibl…

---

## [CairoMakie invert\_normals = true not working](https://discourse.julialang.org/t/cairomakie-invert-normals-true-not-working/104496)

<div class="topic-metadata">

**Author:** [@p\_f](https://discourse.julialang.org/u/p_f)\
**Replies:** 1\
**Last updated:** [October 2, 2023, 12:50pm UTC](https://discourse.julialang.org/t/cairomakie-invert-normals-true-not-working/104496 "2023-10-02T12:50:46Z")

</div>

When plotting surfaces using CairoMakie they appear dull because invert\_normals = true doesn’t seem to work. MWE: code that plots an open sphere using GLMakie and CairoMakie, with invert\_normals=true/false, and saves a …

---

## [Sympy Computation with dsolve for Logistic Differential Equation](https://discourse.julialang.org/t/sympy-computation-with-dsolve-for-logistic-differential-equation/104338)

<div class="topic-metadata">

**Author:** [@Freya\_the\_Goddess](https://discourse.julialang.org/u/Freya_the_Goddess)\
**Replies:** 4\
**Last updated:** [October 2, 2023, 11:53am UTC](https://discourse.julialang.org/t/sympy-computation-with-dsolve-for-logistic-differential-equation/104338 "2023-10-02T11:53:31Z")

</div>

I was computing the solution for: y' = ky(L-y) the solution should be: y(t) = C\_{1} e^{0.6t} (2000 - y(t)) the value of C\_{1} should be 2/3. Thus y(t) = \\frac{4000/3}{2/3 + e^{-0.6t}} I believe I have followed th…

---

## [Can I revert mutations if error is raised inside a function?](https://discourse.julialang.org/t/can-i-revert-mutations-if-error-is-raised-inside-a-function/104452)

<div class="topic-metadata">

**Author:** [@bguillen](https://discourse.julialang.org/u/bguillen)\
**Replies:** 7\
**Last updated:** [October 2, 2023, 9:16am UTC](https://discourse.julialang.org/t/can-i-revert-mutations-if-error-is-raised-inside-a-function/104452 "2023-10-02T09:16:51Z")

</div>

I am writing a few functions for fast median calculation (mostly replicating Alexandrescu’s paper on fast deterministic selection). One of the methods includes assertions that certain assumptions are not violated, howev…

---

## [\`Plots\` or otherwise?](https://discourse.julialang.org/t/plots-or-otherwise/104162)

<div class="topic-metadata">

**Author:** [@ryofurue](https://discourse.julialang.org/u/ryofurue)\
**Replies:** 29\
**Last updated:** [October 2, 2023, 6:41am UTC](https://discourse.julialang.org/t/plots-or-otherwise/104162 "2023-10-02T06:41:17Z")

</div>

After 1.5 years of Julia experience, I now write almost everything in Julia. I used to use Bourne shell, Ruby, Fortran, and a bit of Haskell, but I don’t need these any longer. Except I don’t know which plotting package …

---

## [Startup packages no longer avaiabke when updating using Julia up?](https://discourse.julialang.org/t/startup-packages-no-longer-avaiabke-when-updating-using-julia-up/104478)

<div class="topic-metadata">

**Author:** [@Torkel](https://discourse.julialang.org/u/Torkel)\
**Replies:** 2\
**Last updated:** [October 2, 2023, 5:11am UTC](https://discourse.julialang.org/t/startup-packages-no-longer-avaiabke-when-updating-using-julia-up/104478 "2023-10-02T05:11:23Z")

</div>

I have somewhat recently started using juliaup to keep track of my julia version. I have now updated to the 1.10 beta. Here is the output of juliaup status: Default Channel Version Update …

---

## [Matlab bwpropfilt alternative in Images.jl](https://discourse.julialang.org/t/matlab-bwpropfilt-alternative-in-images-jl/104487)

<div class="topic-metadata">

**Author:** [@Rakesh](https://discourse.julialang.org/u/Rakesh)\
**Replies:** 2\
**Last updated:** [October 2, 2023, 4:27am UTC](https://discourse.julialang.org/t/matlab-bwpropfilt-alternative-in-images-jl/104487 "2023-10-02T04:27:00Z")

</div>

Is there any alternative to Matlab bwpropfilt in Images.jl ecosystem. Thanks.

---

## [Inconsistent results using LoopVectorization @turbo with linear indexing](https://discourse.julialang.org/t/inconsistent-results-using-loopvectorization-turbo-with-linear-indexing/104481)

<div class="topic-metadata">

**Author:** [@james3](https://discourse.julialang.org/u/james3)\
**Replies:** 1\
**Last updated:** [October 2, 2023, 3:08am UTC](https://discourse.julialang.org/t/inconsistent-results-using-loopvectorization-turbo-with-linear-indexing/104481 "2023-10-02T03:08:39Z")

</div>

I am obtaining incorrect results when I combine @turbo with linear indexing of my array. I have a simple example of the issue below. Results are the same except when I combine @turbo with linear indexing. using LoopVect…

---

## [DifferentialEquations.jl change\_t\_via\_interpolation! without save\_everystep for large, expensive ODE](https://discourse.julialang.org/t/differentialequations-jl-change-t-via-interpolation-without-save-everystep-for-large-expensive-ode/104482)

<div class="topic-metadata">

**Author:** [@anicusan](https://discourse.julialang.org/u/anicusan)\
**Replies:** 1\
**Last updated:** [October 2, 2023, 1:14am UTC](https://discourse.julialang.org/t/differentialequations-jl-change-t-via-interpolation-without-save-everystep-for-large-expensive-ode/104482 "2023-10-02T01:14:15Z")

</div>

Hi all, I am writing a domain-specific simulator built on top of DifferentialEquations.jl; I am solving a mathematically simple, but large / expensive system of ODEs (\>10,000), and wish to minimise memory usage by setti…

---

## [ControlSystems.jl Uncertain Model Parameters and Time Delays](https://discourse.julialang.org/t/controlsystems-jl-uncertain-model-parameters-and-time-delays/104373)

<div class="topic-metadata">

**Author:** [@matthew3245](https://discourse.julialang.org/u/matthew3245)\
**Replies:** 9\
**Last updated:** [October 2, 2023, 12:29am UTC](https://discourse.julialang.org/t/controlsystems-jl-uncertain-model-parameters-and-time-delays/104373 "2023-10-02T00:29:27Z")

</div>

I am using ControlSystems.jl with MonteCarloMeasurements.jl to analyse the step response of models with uncertain parameters and time delays. However, plotting the step response of a model with uncertain parameters vs. a…

---

## [Solving PDEs over distributions](https://discourse.julialang.org/t/solving-pdes-over-distributions/104480)

<div class="topic-metadata">

**Author:** [@smartalecH](https://discourse.julialang.org/u/smartalecH)\
**Replies:** 1\
**Last updated:** [October 1, 2023, 11:49pm UTC](https://discourse.julialang.org/t/solving-pdes-over-distributions/104480 "2023-10-01T23:49:18Z")

</div>

Suppose I have an arbitrary PDE solver I’ve built. This solver solves simple linear problems that look like Ax=b. Now suppose I specify a distribution of source terms (the b vector). This could be a straightforward prob…

---

## [Vote: Jupyter Notebook](https://discourse.julialang.org/t/vote-jupyter-notebook/103923)

<div class="topic-metadata">

**Author:** [@ShalokShalom](https://discourse.julialang.org/u/ShalokShalom)\
**Replies:** 1\
**Last updated:** [October 1, 2023, 10:03pm UTC](https://discourse.julialang.org/t/vote-jupyter-notebook/103923 "2023-10-01T22:03:23Z")

</div>

VSCode can create files for languages from its “Select a language” menu, that you surely all know. I started a feature suggestion for VSCode, to include Jupyter Notebooks there as well. Currently, we start them via …

---

## [Binary reading and matrix allocations: most performant way?](https://discourse.julialang.org/t/binary-reading-and-matrix-allocations-most-performant-way/103929)

<div class="topic-metadata">

**Author:** [@myersm0](https://discourse.julialang.org/u/myersm0)\
**Replies:** 3\
**Last updated:** [October 1, 2023, 8:54pm UTC](https://discourse.julialang.org/t/binary-reading-and-matrix-allocations-most-performant-way/103929 "2023-10-01T20:54:04Z")

</div>

Would anyone be able to offer some insight towards getting faster performance for the below sort of use case? Say I have a struct that holds a Matrix and my primary goal is to fill it with values, possibly transposed, a…

---

## [Plot streaming data in Genie.jl](https://discourse.julialang.org/t/plot-streaming-data-in-genie-jl/104476)

<div class="topic-metadata">

**Author:** [@TheLateKronos](https://discourse.julialang.org/u/TheLateKronos)\
**Replies:** 0\
**Last updated:** [October 1, 2023, 7:15pm UTC](https://discourse.julialang.org/t/plot-streaming-data-in-genie-jl/104476 "2023-10-01T19:15:43Z")

</div>

Hey everyone. After browsing through the documentation, I have been unable to find an example of what I have in mind. So I thought I should ask here. Do anyone know if it is possible to plot a streaming dataset in geni…

---

## [Why is the test button red?](https://discourse.julialang.org/t/why-is-the-test-button-red/104474)

<div class="topic-metadata">

**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 5\
**Last updated:** [October 1, 2023, 7:11pm UTC](https://discourse.julialang.org/t/why-is-the-test-button-red/104474 "2023-10-01T19:11:37Z")

</div>

If you look here: GitHub - JuliaGraphics/QML.jl: Build Qt6 QML interfaces for Julia programs. It says “test failing”. But if you click on the button you can see that the tests are not failing. What is going on here?

---

## [General advice for finding Julia jobs?](https://discourse.julialang.org/t/general-advice-for-finding-julia-jobs/104358)

<div class="topic-metadata">

**Author:** [@cscherrer](https://discourse.julialang.org/u/cscherrer)\
**Replies:** 5\
**Last updated:** [October 1, 2023, 6:46pm UTC](https://discourse.julialang.org/t/general-advice-for-finding-julia-jobs/104358 "2023-10-01T18:46:56Z")

</div>

Early in my career, I was lucky enough to find jobs (first a national lab, then a stats consulting company) that were very flexible about choice of language. But in recent years, most data-science-adjacent things I’m see…

---

## [How to compare commits with PkgBenchmark](https://discourse.julialang.org/t/how-to-compare-commits-with-pkgbenchmark/104468)

<div class="topic-metadata">

**Author:** [@Christopher\_Fisher](https://discourse.julialang.org/u/Christopher_Fisher)\
**Replies:** 2\
**Last updated:** [October 1, 2023, 5:25pm UTC](https://discourse.julialang.org/t/how-to-compare-commits-with-pkgbenchmark/104468 "2023-10-01T17:25:54Z")

</div>

Hi, I would like to compare benchmarks for two commits. I’m trying to follow the documentation, but I receive an error indicating that the input is not a repo. I tried a few different approach, but with the same result.…

---

## [How do I make my custom (potentially stupid) model in Julia?](https://discourse.julialang.org/t/how-do-i-make-my-custom-potentially-stupid-model-in-julia/104464)

<div class="topic-metadata">

**Author:** [@Tarny\_GG\_Channie](https://discourse.julialang.org/u/Tarny_GG_Channie)\
**Replies:** 1\
**Last updated:** [October 1, 2023, 2:29pm UTC](https://discourse.julialang.org/t/how-do-i-make-my-custom-potentially-stupid-model-in-julia/104464 "2023-10-01T14:29:43Z")

</div>

Julia is said to be an expressive ML language where you do the obvious thing, putting in math expression and it works. But… how does it work exactly? To try it out, I want to implement my own (potentially stupid) idea fo…

---

## [Is it possible to parallelize matrix division](https://discourse.julialang.org/t/is-it-possible-to-parallelize-matrix-division/104398)

<div class="topic-metadata">

**Author:** [@Shashank](https://discourse.julialang.org/u/Shashank)\
**Replies:** 10\
**Last updated:** [October 1, 2023, 2:18pm UTC](https://discourse.julialang.org/t/is-it-possible-to-parallelize-matrix-division/104398 "2023-10-01T14:18:15Z")

</div>

I have a big (~10000x10000) but sparse matrix A and a vector B. I want to solve the system using backslash C = A\\B , and it works, but it is taking too long. Is there a way to parallelize this and utilize multiple core…

[Previous page](https://discourse.julialang.org/latest.md?page=584)

[Next page](https://discourse.julialang.org/latest.md?page=586)