# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=61

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

**Page:** 62

---

## [Batched gradients and hessians with Flux](https://discourse.julialang.org/t/batched-gradients-and-hessians-with-flux/125130)

<div class="topic-metadata">

**Author:** [@Gattu\_Mytraya](https://discourse.julialang.org/u/Gattu_Mytraya)\
**Replies:** 10\
**Last updated:** [January 25, 2025, 10:55pm UTC](https://discourse.julialang.org/t/batched-gradients-and-hessians-with-flux/125130 "2025-01-25T22:55:35Z")

</div>

Hi, I am new to Flux, so I am not sure how to do the following. Say I have some model(params, x) where the model returns an A dimensional output, there are B params, and x is a C dimensional input. I have D inputs su…

---

## [JuMP.jl optimization which solver](https://discourse.julialang.org/t/jump-jl-optimization-which-solver/125182)

<div class="topic-metadata">

**Author:** [@bernhard](https://discourse.julialang.org/u/bernhard)\
**Replies:** 5\
**Last updated:** [January 25, 2025, 9:48pm UTC](https://discourse.julialang.org/t/jump-jl-optimization-which-solver/125182 "2025-01-25T21:48:10Z")

</div>

I have an optimization problem, but I am unsure which solver to use. I think JuMP.jl might work for this (the problem looks linear to me). Either @objective(....) gives me an error or optimize!(model) errors. The prob…

---

## [Vacuum & Substrate](https://discourse.julialang.org/t/vacuum-substrate/125161)

<div class="topic-metadata">

**Author:** [@Vincenzo\_Pierro](https://discourse.julialang.org/u/Vincenzo_Pierro)\
**Replies:** 5\
**Last updated:** [January 25, 2025, 9:46am UTC](https://discourse.julialang.org/t/vacuum-substrate/125161 "2025-01-25T09:46:06Z")

</div>

how I can define a infinite layer of Vacuum. It is no clear the substrate how can be defined in the structure

---

## [Unexpected coalesced group behaviour in CUDA.jl](https://discourse.julialang.org/t/unexpected-coalesced-group-behaviour-in-cuda-jl/125109)

<div class="topic-metadata">

**Author:** [@eldee](https://discourse.julialang.org/u/eldee)\
**Replies:** 3\
**Last updated:** [January 25, 2025, 8:07am UTC](https://discourse.julialang.org/t/unexpected-coalesced-group-behaviour-in-cuda-jl/125109 "2025-01-25T08:07:31Z")

</div>

Hi, When experimenting a bit with cooperative groups and in particular coalesced groups, I’ve encountered some strange behaviour which I cannot explain. As a simple example, consider using CUDA using CUDA: i32 functio…

---

## [Is it possible to do topology optimization with JuMP.jl?](https://discourse.julialang.org/t/is-it-possible-to-do-topology-optimization-with-jump-jl/125075)

<div class="topic-metadata">

**Author:** [@maphdze](https://discourse.julialang.org/u/maphdze)\
**Replies:** 4\
**Last updated:** [January 24, 2025, 10:49pm UTC](https://discourse.julialang.org/t/is-it-possible-to-do-topology-optimization-with-jump-jl/125075 "2025-01-24T22:49:30Z")

</div>

Hello everyone! I would like to know if it is possible to do topology optimization with JuMP.jl? For topology optimization problems the stiffness matrix changes in each step, could this be formulated in JuMP.jl? In the t…

---

## [Help making ForwardDiff.derivative work](https://discourse.julialang.org/t/help-making-forwarddiff-derivative-work/125167)

<div class="topic-metadata">

**Author:** [@miguelborrero](https://discourse.julialang.org/u/miguelborrero)\
**Replies:** 2\
**Last updated:** [January 24, 2025, 1:42pm UTC](https://discourse.julialang.org/t/help-making-forwarddiff-derivative-work/125167 "2025-01-24T13:42:45Z")

</div>

Hi there, I define my custom parametric types as follows: struct Parameters{T} """ inmutable type to pack the parameters estimated. """ ϕ::T λ::T γ₁::T end struct MarketPostEstimation{T} …

---

## [How to save Plots.jl with pgfplotsx() without dimensions and other properties?](https://discourse.julialang.org/t/how-to-save-plots-jl-with-pgfplotsx-without-dimensions-and-other-properties/112158)

<div class="topic-metadata">

**Author:** [@homocomputeris](https://discourse.julialang.org/u/homocomputeris)\
**Replies:** 1\
**Last updated:** [January 24, 2025, 11:31am UTC](https://discourse.julialang.org/t/how-to-save-plots-jl-with-pgfplotsx-without-dimensions-and-other-properties/112158 "2025-01-24T11:31:10Z")

</div>

Plots.jl saves pgfplotsx() figures like this: ... width={150.4mm}, height={99.6mm}, xlabel style={...}, ylabel style={...}, ... How do I prevent these properties from being written to the file?

---

## [Non-Differentiable Constraints](https://discourse.julialang.org/t/non-differentiable-constraints/125113)

<div class="topic-metadata">

**Author:** [@Alessio\_Bellisomi](https://discourse.julialang.org/u/Alessio_Bellisomi)\
**Replies:** 3\
**Last updated:** [January 24, 2025, 10:18am UTC](https://discourse.julialang.org/t/non-differentiable-constraints/125113 "2025-01-24T10:18:03Z")

</div>

I am trying to write an optimization routine for insurance book. The target is to be able to increase the return without affecting the tail value at risk by modifying the shares for each contract. This is an example of …

---

## [Feature proposal: Saving symbolic derivatives](https://discourse.julialang.org/t/feature-proposal-saving-symbolic-derivatives/124956)

<div class="topic-metadata">

**Author:** [@KSepetanc](https://discourse.julialang.org/u/KSepetanc)\
**Replies:** 2\
**Last updated:** [January 24, 2025, 9:55am UTC](https://discourse.julialang.org/t/feature-proposal-saving-symbolic-derivatives/124956 "2025-01-24T09:55:14Z")

</div>

@odow I am starting discussion about new feature for MathOptSymbolicAD.jl . I think adding option to save symbolic derivative expressions to file would be useful. Many of us develop applications where we do not care ab…

---

## [How to refer to a JuMP variable using a string when the model is defined in a module?](https://discourse.julialang.org/t/how-to-refer-to-a-jump-variable-using-a-string-when-the-model-is-defined-in-a-module/125122)

<div class="topic-metadata">

**Author:** [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Replies:** 3\
**Last updated:** [January 24, 2025, 8:23am UTC](https://discourse.julialang.org/t/how-to-refer-to-a-jump-variable-using-a-string-when-the-model-is-defined-in-a-module/125122 "2025-01-24T08:23:26Z")

</div>

Hello, in a JuMP model I need to fix some variables, and these variables to fix are defined in a dictionary. This works: using JuMP, Ipopt fvars = Dict{String,Float64}("c" =\> 5) m = Model(Ipopt.Optimizer) # \[...\] @va…

---

## [MLX and Apple silicon](https://discourse.julialang.org/t/mlx-and-apple-silicon/125136)

<div class="topic-metadata">

**Author:** [@Hareruya](https://discourse.julialang.org/u/Hareruya)\
**Replies:** 4\
**Last updated:** [January 24, 2025, 2:44am UTC](https://discourse.julialang.org/t/mlx-and-apple-silicon/125136 "2025-01-24T02:44:02Z")

</div>

Good evening. I have recently bought an M4 MacbookPro Max and have been using it to do some programming in my free time, messing around with image processing on the side. The machine is very powerful and energy efficien…

---

## [Placing dotplot over violin plot](https://discourse.julialang.org/t/placing-dotplot-over-violin-plot/115253)

<div class="topic-metadata">

**Author:** [@Max\_Beez](https://discourse.julialang.org/u/Max_Beez)\
**Replies:** 6\
**Last updated:** [January 23, 2025, 3:42pm UTC](https://discourse.julialang.org/t/placing-dotplot-over-violin-plot/115253 "2025-01-23T15:42:41Z")

</div>

I am trying to create a violin plot with the individual data points overlayed over the violin plot. IF I create a violin using Plots.violin(data) and then dotplot!(data) I get a result of side-by-side rather than overlay…

---

## [Learning Machine Learning (SVM) with Julia](https://discourse.julialang.org/t/learning-machine-learning-svm-with-julia/36083)

<div class="topic-metadata">

**Author:** [@Fred](https://discourse.julialang.org/u/Fred)\
**Replies:** 10\
**Last updated:** [March 18, 2020, 4:38pm UTC](https://discourse.julialang.org/t/learning-machine-learning-svm-with-julia/36083 "2020-03-18T16:38:42Z")

</div>

Hi ! I would like to learn machine learning, SVM in particular. I am a complete newbie and I search few advices from experimented user before starting. 1- Is it a good idea to learn SVM with Julia or it will be much mo…

---

## [Fitting a truncated distribution](https://discourse.julialang.org/t/fitting-a-truncated-distribution/125067)

<div class="topic-metadata">

**Author:** [@johannesnauta](https://discourse.julialang.org/u/johannesnauta)\
**Replies:** 0\
**Last updated:** [January 22, 2025, 10:33am UTC](https://discourse.julialang.org/t/fitting-a-truncated-distribution/125067 "2025-01-22T10:33:22Z")

</div>

In Distributions.jl, is there no build-in functionality to fit truncated distributions? Of course I can write a small routine to do this, but either I cannot find documentation on it, or it is perhaps not implemented? If…

---

## [JuMP register function](https://discourse.julialang.org/t/jump-register-function/125099)

<div class="topic-metadata">

**Author:** [@Sushrut\_Deshpande](https://discourse.julialang.org/u/Sushrut_Deshpande)\
**Replies:** 4\
**Last updated:** [January 23, 2025, 6:33am UTC](https://discourse.julialang.org/t/jump-register-function/125099 "2025-01-23T06:33:44Z")

</div>

Hello, This is my first time using JuMP hence my question is basic. The following fails using JuMP, Ipopt f(x) = x\[1\]^2 + x\[2\]^2 ∇f(x) = \[2\*x\[1\], 2\*x\[2\]\] ∇²f(x) = \[2 0; 0 2\] model = Model(Ipopt.Optimizer) register(mo…

---

## [Makie recipe to plot ODESolution of DifferentialEquations.jl?](https://discourse.julialang.org/t/makie-recipe-to-plot-odesolution-of-differentialequations-jl/105879)

<div class="topic-metadata">

**Author:** [@homocomputeris](https://discourse.julialang.org/u/homocomputeris)\
**Replies:** 11\
**Last updated:** [January 23, 2025, 12:28am UTC](https://discourse.julialang.org/t/makie-recipe-to-plot-odesolution-of-differentialequations-jl/105879 "2025-01-23T00:28:55Z")

</div>

Related to this question. Is there a recipe to plot the DiffEq solution components against time? I tried Makie.convert\_arguments(sol::ODESolution) = (sol.t, \[\[v\[1\] for v in sol.u\], \[\[v\[2\] for v in sol.u\]\]\]) but it pl…

---

## [Updates to JuMP dependencies (MathOptInterface) affecting results](https://discourse.julialang.org/t/updates-to-jump-dependencies-mathoptinterface-affecting-results/125058)

<div class="topic-metadata">

**Author:** [@nealhughes](https://discourse.julialang.org/u/nealhughes)\
**Replies:** 3\
**Last updated:** [January 22, 2025, 7:22pm UTC](https://discourse.julialang.org/t/updates-to-jump-dependencies-mathoptinterface-affecting-results/125058 "2025-01-22T19:22:56Z")

</div>

I have a large JuMP project developed on older versions of Julia (1.7.0) and JuMP (1.22.1) (because I was stuck on a corporate IT system and it was hard to update). I’ve since moved my project to a new IT system, and us…

---

## [Organising JuliaAstro meeting](https://discourse.julialang.org/t/organising-juliaastro-meeting/72313)

<div class="topic-metadata">

**Author:** [@giordano](https://discourse.julialang.org/u/giordano)\
**Replies:** 5\
**Last updated:** [January 22, 2025, 3:01pm UTC](https://discourse.julialang.org/t/organising-juliaastro-meeting/72313 "2025-01-22T15:01:56Z")

</div>

We’re organising the first JuliaAstro call! This will be a very preliminary meeting, to know each other and talk about the development of Julia packages in the astronomy/astrophysics domain. If you’re interest in this …

---

## [Makie log scale axis with nicer ticks](https://discourse.julialang.org/t/makie-log-scale-axis-with-nicer-ticks/125062)

<div class="topic-metadata">

**Author:** [@Oto\_Brzobohaty](https://discourse.julialang.org/u/Oto_Brzobohaty)\
**Replies:** 3\
**Last updated:** [January 22, 2025, 1:02pm UTC](https://discourse.julialang.org/t/makie-log-scale-axis-with-nicer-ticks/125062 "2025-01-22T13:02:57Z")

</div>

Is there any way how to set the ticks in log scale axis automatically (default) to be only 10^N, where N is an integer? I do not like the 10^0.5 10^1.5 etc.

---

## [Virtual (or lazy) representation of a repeated array](https://discourse.julialang.org/t/virtual-or-lazy-representation-of-a-repeated-array/124954)

<div class="topic-metadata">

**Author:** [@Alexander-Barth](https://discourse.julialang.org/u/Alexander-Barth)\
**Replies:** 4\
**Last updated:** [January 22, 2025, 12:22pm UTC](https://discourse.julialang.org/t/virtual-or-lazy-representation-of-a-repeated-array/124954 "2025-01-22T12:22:50Z")

</div>

Is there an array type, that allows me to create a virtual (or lazy) representation of the following array x ? sz = (64, 64, 2, 10589) tmp = reshape(range(-1,1,64),(:,1,1,1)); x = repeat(tmp,1,sz\[2\],sz\[3\],sz\[4\]); It …

---

## [Agents abmexploration callback errors in "on hover"](https://discourse.julialang.org/t/agents-abmexploration-callback-errors-in-on-hover/124675)

<div class="topic-metadata">

**Author:** [@Niall](https://discourse.julialang.org/u/Niall)\
**Replies:** 7\
**Last updated:** [January 22, 2025, 10:38am UTC](https://discourse.julialang.org/t/agents-abmexploration-callback-errors-in-on-hover/124675 "2025-01-22T10:38:18Z")

</div>

Hi. I’m struggling a bit with understanding all the details of using abmexploration with the Agents package. I got occasional crashes with small models, but they greatly increased with large numbers of agents. Finally, I…

---

## [Working with JDBC in Julia](https://discourse.julialang.org/t/working-with-jdbc-in-julia/125030)

<div class="topic-metadata">

**Author:** [@GregorM](https://discourse.julialang.org/u/GregorM)\
**Replies:** 1\
**Last updated:** [January 22, 2025, 10:37am UTC](https://discourse.julialang.org/t/working-with-jdbc-in-julia/125030 "2025-01-22T10:37:09Z")

</div>

In the last couple of years I have been using Julia for various data projects in different companies. What I’m always struggling with is getting all the needed data out of a database. In most cases databases can be acces…

---

## [Unsatisfying results from the calibration of a model](https://discourse.julialang.org/t/unsatisfying-results-from-the-calibration-of-a-model/124912)

<div class="topic-metadata">

**Author:** [@Iforire](https://discourse.julialang.org/u/Iforire)\
**Replies:** 3\
**Last updated:** [January 22, 2025, 9:17am UTC](https://discourse.julialang.org/t/unsatisfying-results-from-the-calibration-of-a-model/124912 "2025-01-22T09:17:54Z")

</div>

Hi everyone, First of all, I am quite new to Julia and not at all an expert in either coding or optimization/modelling! I want to calibate the following model with 2 parameters to calibrate (K\[1\] and K\[2\]) and 2 variab…

---

## [Bilevel JuMP](https://discourse.julialang.org/t/bilevel-jump/44068)

<div class="topic-metadata">

**Author:** [@dty](https://discourse.julialang.org/u/dty)\
**Replies:** 50\
**Last updated:** [January 22, 2025, 3:59am UTC](https://discourse.julialang.org/t/bilevel-jump/44068 "2025-01-22T03:59:34Z")

</div>

How to define the right objective function in jump？Is there a problem with my definition? In addition, if the objective function is composed of multiple sub functions and cannot be represented by a single formula, the su…

---

## [Makie - \`\]test Makie\` 1 test stuck?](https://discourse.julialang.org/t/makie-test-makie-1-test-stuck/125038)

<div class="topic-metadata">

**Author:** [@p\_f](https://discourse.julialang.org/u/p_f)\
**Replies:** 0\
**Last updated:** [January 21, 2025, 6:49pm UTC](https://discourse.julialang.org/t/makie-test-makie-1-test-stuck/125038 "2025-01-21T18:49:40Z")

</div>

Hi, I’ve attempted to fix a bug in Makie, and am attempting to run the tests. I’ve got an environment with Makie, GLMakie, CairoMakie and ReferenceTests all dev’d. I then typed \]test Makie. tests never finished, so I c…

---

## [Solver and AD advice for nonlinear LS problem](https://discourse.julialang.org/t/solver-and-ad-advice-for-nonlinear-ls-problem/125014)

<div class="topic-metadata">

**Author:** [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Replies:** 5\
**Last updated:** [January 21, 2025, 5:26pm UTC](https://discourse.julialang.org/t/solver-and-ad-advice-for-nonlinear-ls-problem/125014 "2025-01-21T17:26:51Z")

</div>

(This is a vague open-ended question for which I cannot provide an MWE.) I have a nonlinear least squares problem \\min\_x \\| f(x) \\|\_2^2 where x \\in \\mathbb{R}^N, N \\approx 20...40, and f(x) has about 100–200 elements…

---

## [Changing the relstep of AutoFiniteDiff() in an OptimizationFunction](https://discourse.julialang.org/t/changing-the-relstep-of-autofinitediff-in-an-optimizationfunction/125004)

<div class="topic-metadata">

**Author:** [@Bart\_van\_de\_Lint](https://discourse.julialang.org/u/Bart_van_de_Lint)\
**Replies:** 5\
**Last updated:** [January 21, 2025, 11:19am UTC](https://discourse.julialang.org/t/changing-the-relstep-of-autofinitediff-in-an-optimizationfunction/125004 "2025-01-21T11:19:58Z")

</div>

I want to define an OptimizationProblem using Optimization.jl and FiniteDiff: optf = OptimizationFunction(f\_zero, AutoFiniteDiff()) prob = OptimizationProblem(optf, \[stretched\_tether\_length - 0.05, 0.0, 0.0, 0.0…

---

## [Errors in Discretization in ModelingToolkit.jl](https://discourse.julialang.org/t/errors-in-discretization-in-modelingtoolkit-jl/124403)

<div class="topic-metadata">

**Author:** [@JustPickedThisUp](https://discourse.julialang.org/u/JustPickedThisUp)\
**Replies:** 5\
**Last updated:** [January 21, 2025, 10:25am UTC](https://discourse.julialang.org/t/errors-in-discretization-in-modelingtoolkit-jl/124403 "2025-01-21T10:25:17Z")

</div>

Hello, I’ve been trying to solve this time dependent Schrodingers equation with these conditions: It keeps throwing up errors like AssertionError: There must be the same number of equations and unknowns, got 2 equat…

---

## [Help with continuation using BifurcationKit.jl](https://discourse.julialang.org/t/help-with-continuation-using-bifurcationkit-jl/124965)

<div class="topic-metadata">

**Author:** [@iclo3](https://discourse.julialang.org/u/iclo3)\
**Replies:** 4\
**Last updated:** [January 21, 2025, 9:15am UTC](https://discourse.julialang.org/t/help-with-continuation-using-bifurcationkit-jl/124965 "2025-01-21T09:15:49Z")

</div>

Hello all, Relatively new to BifurcationKit (I have used other continuation software in the past). I’ve been able to get a 2D system (quite similar to the 3D system I’m having trouble with) to work, so any help or advic…

---

## [Control on density plot marker shape and color](https://discourse.julialang.org/t/control-on-density-plot-marker-shape-and-color/124846)

<div class="topic-metadata">

**Author:** [@Nick1](https://discourse.julialang.org/u/Nick1)\
**Replies:** 3\
**Last updated:** [January 21, 2025, 7:12am UTC](https://discourse.julialang.org/t/control-on-density-plot-marker-shape-and-color/124846 "2025-01-21T07:12:47Z")

</div>

I am trying to plot different probability densities on the same plot from a data frame, based on a group. However, there is an overlap on the lines and I need to use different marker shapes and colors for better visibili…

[Previous page](https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=60)

[Next page](https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=62)