# Specific Domains **URL:** https://discourse.julialang.org/c/domain/10.md?page=7 [Latest](https://discourse.julialang.org/latest.md) · [Categories](https://discourse.julialang.org/categories.md) · [Tags](https://discourse.julialang.org/tags.md) **Page:** 8 --- ## [Avoiding Mutation vs Allocation](https://discourse.julialang.org/t/avoiding-mutation-vs-allocation/137123)
**Author:** [@johnb](https://discourse.julialang.org/u/johnb)\ **Replies:** 7\ **Last updated:** [May 15, 2026, 2:35pm UTC](https://discourse.julialang.org/t/avoiding-mutation-vs-allocation/137123 "2026-05-15T14:35:33Z")
I’ve been writing code for dynamic models in Julia for a few years now, and I keep running into a conflict between allocations and mutation. To improve ODE solve performance, I need to write in-place functions and preall… --- ## [More Barplots](https://discourse.julialang.org/t/more-barplots/137117)
**Author:** [@Mervyn\_Larrier](https://discourse.julialang.org/u/Mervyn_Larrier)\ **Replies:** 10\ **Last updated:** [May 15, 2026, 11:02am UTC](https://discourse.julialang.org/t/more-barplots/137117 "2026-05-15T11:02:03Z")
Hi all. Round two of figuring out bar plots in Makie. Given the data, I would like to plot one set of data and then stack the other data on top of it. In my last question, my issue was resolved with the n\_dodge attribute… --- ## [Error and Segfault with DeviceIterator for parallel DataLoader on sharded ReactantDevice](https://discourse.julialang.org/t/error-and-segfault-with-deviceiterator-for-parallel-dataloader-on-sharded-reactantdevice/137074)
**Author:** [@benjwweber](https://discourse.julialang.org/u/benjwweber)\ **Replies:** 1\ **Last updated:** [May 14, 2026, 10:28pm UTC](https://discourse.julialang.org/t/error-and-segfault-with-deviceiterator-for-parallel-dataloader-on-sharded-reactantdevice/137074 "2026-05-14T22:28:16Z")
I am trying to load a data set via a DataLoader/DeviceIterator to a sharded ReactantDevice. I have replicated it here with a mock data set. However I run into a variety of errors or segfaults if I do this. Is there anyth… --- ## [Supressing "Info:" in XGBoost package?](https://discourse.julialang.org/t/supressing-info-in-xgboost-package/137121)
**Author:** [@Snowy](https://discourse.julialang.org/u/Snowy)\ **Replies:** 1\ **Last updated:** [May 14, 2026, 4:16pm UTC](https://discourse.julialang.org/t/supressing-info-in-xgboost-package/137121 "2026-05-14T16:16:51Z")
Hi, When training an XGBoost the xgboost.jl package provides information about the rmse value: This is helpful when training first but when running in production I might not want my terminal to be filled with this, … --- ## [Makie Bar Plots](https://discourse.julialang.org/t/makie-bar-plots/137098)
**Author:** [@Mervyn\_Larrier](https://discourse.julialang.org/u/Mervyn_Larrier)\ **Replies:** 3\ **Last updated:** [May 13, 2026, 4:50pm UTC](https://discourse.julialang.org/t/makie-bar-plots/137098 "2026-05-13T16:50:06Z")
I feel as though I’m probably missing something obvious, but there don’t seem to be a lot of examples for bar plots in Makie that don’t point you back towards AoG. How can I get these bars to be properly dodged? Here is … --- ## [Oxygen.jl is faster than FastAPI, Flask and Rocket](https://discourse.julialang.org/t/oxygen-jl-is-faster-than-fastapi-flask-and-rocket/100389)
**Author:** [@Jose\_Diaz](https://discourse.julialang.org/u/Jose_Diaz)\ **Replies:** 9\ **Last updated:** [May 12, 2026, 12:18pm UTC](https://discourse.julialang.org/t/oxygen-jl-is-faster-than-fastapi-flask-and-rocket/100389 "2026-05-12T12:18:54Z")
Running some benchmarks ---- 1000 HTTP Requests ---- Flask Server --- 1.7611534595489502 seconds in total --- --- 0.0017611534595489502 seconds per iteration --- FastAPI Server --- 1.5010621547698975 seconds in total --… --- ## [Kernel Density Estimate boundary problems](https://discourse.julialang.org/t/kernel-density-estimate-boundary-problems/115200)
**Author:** [@vh94](https://discourse.julialang.org/u/vh94)\ **Replies:** 6\ **Last updated:** [May 11, 2026, 7:17am UTC](https://discourse.julialang.org/t/kernel-density-estimate-boundary-problems/115200 "2026-05-11T07:17:57Z")
Hello everyone, I am currently trying to calculate probability density curves using the KernelDensity.jl package, however I ran into some issues due to the nature of my data. I am not a statistician so i will have to e… --- ## [How to train dense nets several times faster than with Adam](https://discourse.julialang.org/t/how-to-train-dense-nets-several-times-faster-than-with-adam/137009)
**Author:** [@uwestoehr](https://discourse.julialang.org/u/uwestoehr)\ **Replies:** 4\ **Last updated:** [May 8, 2026, 10:36am UTC](https://discourse.julialang.org/t/how-to-train-dense-nets-several-times-faster-than-with-adam/137009 "2026-05-08T10:36:59Z")
I had the pleasure to give a lecture about the basics of neural nets at a university and purposely used Julia also for the practical lessons. As a side effect I wanted to explain my students how an optimizer can be deri… --- ## [Plots bug - arrows & xflip?](https://discourse.julialang.org/t/plots-bug-arrows-xflip/137024)
**Author:** [@BLI](https://discourse.julialang.org/u/BLI)\ **Replies:** 2\ **Last updated:** [May 7, 2026, 7:44pm UTC](https://discourse.julialang.org/t/plots-bug-arrows-xflip/137024 "2026-05-07T19:44:23Z")
Consider: plot(sin; lw=2, xlim=\[0,2pi\],label="") plot!(\[(1,-0.5),(pi,0)\]; lw=2, lc=:red, arrow=arrow(:closed, :head, 2.0, 2.0), label="") providing (as expected): But if I flip the x axis, I get something “wrong”… … --- ## [Tree-Structured Parzen Estimator (TPE) algorithm](https://discourse.julialang.org/t/tree-structured-parzen-estimator-tpe-algorithm/137001)
**Author:** [@Resul.Akay](https://discourse.julialang.org/u/Resul.Akay)\ **Replies:** 1\ **Last updated:** [May 6, 2026, 8:37am UTC](https://discourse.julialang.org/t/tree-structured-parzen-estimator-tpe-algorithm/137001 "2026-05-06T08:37:49Z")
Hello everyone, Is there any package that implements Tree-Structured Parzen Estimator (TPE) algorithm in Julia. TPE is the same algorithm behind Optuna and Hyperopt, two of the most widely used hyperparameter tuning fr… --- ## [API for FB Prophet model](https://discourse.julialang.org/t/api-for-fb-prophet-model/74138)
**Author:** [@mobar](https://discourse.julialang.org/u/mobar)\ **Replies:** 11\ **Last updated:** [May 6, 2026, 2:11am UTC](https://discourse.julialang.org/t/api-for-fb-prophet-model/74138 "2026-05-06T02:11:52Z")
Has anyone yet created an eay-to-use API in Julia for Facebook’s prophet model with a basic “fit” and “predict” functionality? (Quick Start | Prophet) I’m simply asking because there’s a good chance someone also has al… --- ## [Plots/GR & fill color of shapes?](https://discourse.julialang.org/t/plots-gr-fill-color-of-shapes/136993)
**Author:** [@BLI](https://discourse.julialang.org/u/BLI)\ **Replies:** 0\ **Last updated:** [May 5, 2026, 4:18pm UTC](https://discourse.julialang.org/t/plots-gr-fill-color-of-shapes/136993 "2026-05-05T16:18:48Z")
I figured it out – it was a stupidity done by Google AI Studio… for some weird reason, it had added a rectangle on top of the white rectangle… Arrrrghhhh --- ## [How to contribute an optimizer to the Optimisers.jl package](https://discourse.julialang.org/t/how-to-contribute-an-optimizer-to-the-optimisers-jl-package/136975)
**Author:** [@uwestoehr](https://discourse.julialang.org/u/uwestoehr)\ **Replies:** 0\ **Last updated:** [May 4, 2026, 4:07am UTC](https://discourse.julialang.org/t/how-to-contribute-an-optimizer-to-the-optimisers-jl-package/136975 "2026-05-04T04:07:17Z")
Since almost 2 years I use Flux and Lux and thus the Optimisers.jl package. Since I need for scientific reasons also tests with optimizers not supported by the Optimisers.jl package, I wrote them for my own. I want now … --- ## [Multi objective Markov decision processes](https://discourse.julialang.org/t/multi-objective-markov-decision-processes/111982)
**Author:** [@slwu89](https://discourse.julialang.org/u/slwu89)\ **Replies:** 11\ **Last updated:** [May 3, 2026, 10:49am UTC](https://discourse.julialang.org/t/multi-objective-markov-decision-processes/111982 "2026-05-03T10:49:14Z")
Hi all. If this is the wrong section, please let me know and I’ll move my question. I am curious if there is any work on multi-objective MDPs in Julia. I’m not very familiar with the MDP landscape in Julia; I perused th… --- ## [Subplots and axis labels](https://discourse.julialang.org/t/subplots-and-axis-labels/136960)
**Author:** [@bernardofpc](https://discourse.julialang.org/u/bernardofpc)\ **Replies:** 1\ **Last updated:** [May 2, 2026, 1:37pm UTC](https://discourse.julialang.org/t/subplots-and-axis-labels/136960 "2026-05-02T13:37:26Z")
I’ve been using Plots.jl for some time, but never managed to figure out the correct way of producing a figure with subplots and axis labels. In most cases, it seems axis labels are positioned outside of the plot area, a… --- ## [Gurobi fails to invoke the primal simplex method when doing column generation?](https://discourse.julialang.org/t/gurobi-fails-to-invoke-the-primal-simplex-method-when-doing-column-generation/133675)
**Author:** [@WalterMadelim](https://discourse.julialang.org/u/WalterMadelim)\ **Replies:** 18\ **Last updated:** [April 30, 2026, 9:17pm UTC](https://discourse.julialang.org/t/gurobi-fails-to-invoke-the-primal-simplex-method-when-doing-column-generation/133675 "2026-04-30T21:17:20Z")
I have a refreshing discovery today, based on my acquaintance Column generation · JuMP wherein, the only thing I changed was the solver (I used Gurobi instead of HiGHS). This is the master LP’s re-solving logging I acq… --- ## [Speed issue for Quadratic Program](https://discourse.julialang.org/t/speed-issue-for-quadratic-program/136898)
**Author:** [@vaibhav.u](https://discourse.julialang.org/u/vaibhav.u)\ **Replies:** 4\ **Last updated:** [April 30, 2026, 9:16pm UTC](https://discourse.julialang.org/t/speed-issue-for-quadratic-program/136898 "2026-04-30T21:16:30Z")
I am dealing with a projection problem in a space defined by multiple linear constraints, with a problem dimension of about 1000, and I have 1000 such problems in a ‘for’ loop. I initially used the OSQP solver with JuMP,… --- ## [How to update Makie.jl plot based on ComputeGraph?](https://discourse.julialang.org/t/how-to-update-makie-jl-plot-based-on-computegraph/136730)
**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\ **Replies:** 12\ **Last updated:** [April 29, 2026, 8:29pm UTC](https://discourse.julialang.org/t/how-to-update-makie-jl-plot-based-on-computegraph/136730 "2026-04-29T20:29:18Z")
I am using the ComputeGraph feature of Makie.jl for the first time. After adding widgets (observables) as nodes in the graph, I also added nodes for the plot objects: # initialize scene with elements # that do not depen… --- ## [MTK programmatic populating initial guess values](https://discourse.julialang.org/t/mtk-programmatic-populating-initial-guess-values/136912)
**Author:** [@mark.garnett](https://discourse.julialang.org/u/mark.garnett)\ **Replies:** 4\ **Last updated:** [April 29, 2026, 3:36pm UTC](https://discourse.julialang.org/t/mtk-programmatic-populating-initial-guess-values/136912 "2026-04-29T15:36:34Z")
Hi all, this should be really easy but I can’t quite figure it out. When you create an MTK system, and want to solve it as a NonlinearProblem, ODEProblem, or whatever, you often need provide an initial guess or initial … --- ## [Makie: how to add some gap to the right end of a figure?](https://discourse.julialang.org/t/makie-how-to-add-some-gap-to-the-right-end-of-a-figure/136907)
**Author:** [@Datseris](https://discourse.julialang.org/u/Datseris)\ **Replies:** 5\ **Last updated:** [April 29, 2026, 9:08am UTC](https://discourse.julialang.org/t/makie-how-to-add-some-gap-to-the-right-end-of-a-figure/136907 "2026-04-29T09:08:39Z")
I have a figure that is composed of two columns. Each column is itself a GridLayout. I am having the problem that on the right end of the figure, the axes labels go over the figure boundary: How do I fix this? I don’t… --- ## [CUDA.jl with @threads causing memory leak?](https://discourse.julialang.org/t/cuda-jl-with-threads-causing-memory-leak/136853)
**Author:** [@noetheriankoala](https://discourse.julialang.org/u/noetheriankoala)\ **Replies:** 3\ **Last updated:** [April 27, 2026, 10:23pm UTC](https://discourse.julialang.org/t/cuda-jl-with-threads-causing-memory-leak/136853 "2026-04-27T22:23:37Z")
Hello. First of all, I am using Julia v1.12.6, CUDA v5.11.2, and FLoops v0.2.2. Consider the following code and comments. using CUDA using Base.Threads function func1() A = CuArray{Float64}(undef, 1500, 1500, 1000)… --- ## [JuMP: unused \`@operator\` has critical impact](https://discourse.julialang.org/t/jump-unused-operator-has-critical-impact/136895)
**Author:** [@cstjean](https://discourse.julialang.org/u/cstjean)\ **Replies:** 2\ **Last updated:** [April 27, 2026, 5:45am UTC](https://discourse.julialang.org/t/jump-unused-operator-has-critical-impact/136895 "2026-04-27T05:45:25Z")
I have some model defined like fake\_fun(a,b) = 0 function my\_model() ... @operator(m, unused\_op, 2, fake\_fun) ... end where both unused\_op and fake\_fun are not used anywhere except on that line. With thi… --- ## [Modify axis options when using Plots.jl with pgfplotsx backend](https://discourse.julialang.org/t/modify-axis-options-when-using-plots-jl-with-pgfplotsx-backend/121292)
**Author:** [@lcm](https://discourse.julialang.org/u/lcm)\ **Replies:** 3\ **Last updated:** [April 26, 2026, 4:31pm UTC](https://discourse.julialang.org/t/modify-axis-options-when-using-plots-jl-with-pgfplotsx-backend/121292 "2026-04-26T16:31:33Z")
I am using Plots.jl with the pgfplotsx() backend for emitting .tikz files. Together with the tikzscale LaTeX package this makes for nice plots for a TeX document. However, in the emitted plots there are a lot of options… --- ## [AD over runtime-selected fields in nested structs — design patterns?](https://discourse.julialang.org/t/ad-over-runtime-selected-fields-in-nested-structs-design-patterns/136882)
**Author:** [@stevenhughes](https://discourse.julialang.org/u/stevenhughes)\ **Replies:** 4\ **Last updated:** [April 26, 2026, 12:10pm UTC](https://discourse.julialang.org/t/ad-over-runtime-selected-fields-in-nested-structs-design-patterns/136882 "2026-04-26T12:10:49Z")
We have a framework where users define models as nested structs and declare at runtime which fields are optimization variables. The framework then needs to differentiate constraints/objectives with respect to those selec… --- ## [Error 10005: Cannot retrieve UnbdRay from Gurobi](https://discourse.julialang.org/t/error-10005-cannot-retrieve-unbdray-from-gurobi/136886)
**Author:** [@WalterMadelim](https://discourse.julialang.org/u/WalterMadelim)\ **Replies:** 4\ **Last updated:** [April 26, 2026, 11:39am UTC](https://discourse.julialang.org/t/error-10005-cannot-retrieve-unbdray-from-gurobi/136886 "2026-04-26T11:39:08Z")
Is this a bug? julia\> Gurobi.GRBsetdblattrarray(lps.o, "Obj", 1, xllen, mst.Xlb) 0 julia\> function opt\_and\_ter(m) # my definition of optimize! and return Gurobi's termination code o, r = m.o, m.refi … --- ## [Ignore masked tokens (Flux.jl)](https://discourse.julialang.org/t/ignore-masked-tokens-flux-jl/75591)
**Author:** [@spragud2](https://discourse.julialang.org/u/spragud2)\ **Replies:** 6\ **Last updated:** [April 24, 2026, 7:56pm UTC](https://discourse.julialang.org/t/ignore-masked-tokens-flux-jl/75591 "2026-04-24T19:56:14Z")
Hi, I’m working on implementing a seq2seq model in Flux. Is there a standard method, or if not a suitable approach, for ignoring masked tokens when computing the gradient? E.g. sentences of differing lengths, following … --- ## [Makie: WGLMakie after reverse proxy (nginx)](https://discourse.julialang.org/t/makie-wglmakie-after-reverse-proxy-nginx/136847)
**Author:** [@dmolina](https://discourse.julialang.org/u/dmolina)\ **Replies:** 6\ **Last updated:** [April 24, 2026, 9:45am UTC](https://discourse.julialang.org/t/makie-wglmakie-after-reverse-proxy-nginx/136847 "2026-04-24T09:45:06Z")
Dear all, I have a notebook in Pluto/PlutoSliderServer with several interactive graphics in a server for my students. My previous version was using Plots, but it was awfully slow, so I decided to try the WGLMakie and Ob… --- ## [Unpredictable Compilation Performance of MTK-Generated Functions](https://discourse.julialang.org/t/unpredictable-compilation-performance-of-mtk-generated-functions/136827)
**Author:** [@chen\_hardworking](https://discourse.julialang.org/u/chen_hardworking)\ **Replies:** 19\ **Last updated:** [April 24, 2026, 5:14am UTC](https://discourse.julialang.org/t/unpredictable-compilation-performance-of-mtk-generated-functions/136827 "2026-04-24T05:14:18Z")
Problem Statement: I am reporting a critical bottleneck regarding the compilation and loading stability of functions generated by ModelingToolkit.jl. My experience shows that the complexity of the generated symbolic Jaco… --- ## [Number of threads assigned via SLURM](https://discourse.julialang.org/t/number-of-threads-assigned-via-slurm/136820)
**Author:** [@pulk\_jain](https://discourse.julialang.org/u/pulk_jain)\ **Replies:** 5\ **Last updated:** [April 24, 2026, 4:50am UTC](https://discourse.julialang.org/t/number-of-threads-assigned-via-slurm/136820 "2026-04-24T04:50:26Z")
I am trying to run some multi-threaded code on a cluster using SLURM. #SBATCH --cpus-per-task=4 JPATH=$HOME/.juliaup/bin export JULIA\_DEPOT\_PATH="/my/storage/dir/.julia:" export JULIA\_NUM\_THREADS=auto $JPATH/julia main\_… --- ## [How to improve structural\_simplify performance?](https://discourse.julialang.org/t/how-to-improve-structural-simplify-performance/127260)
**Author:** [@Bart\_van\_de\_Lint](https://discourse.julialang.org/u/Bart_van_de_Lint)\ **Replies:** 17\ **Last updated:** [April 23, 2026, 4:08am UTC](https://discourse.julialang.org/t/how-to-improve-structural-simplify-performance/127260 "2026-04-23T04:08:24Z")
Modelingtoolkits structural\_simplify can be very slow on bigger systems. What can I do to improve it’s performance? Should I write my equations in a certain way, should I split up big equations into smaller ones, or shou… [Previous page](https://discourse.julialang.org/c/domain/10.md?page=6) [Next page](https://discourse.julialang.org/c/domain/10.md?page=8)