# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=64

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

**Page:** 65

---

## [Choosing a convention for complex numbers in DifferentiationInterface](https://discourse.julialang.org/t/choosing-a-convention-for-complex-numbers-in-differentiationinterface/124433)

<div class="topic-metadata">

**Author:** [@gdalle](https://discourse.julialang.org/u/gdalle)\
**Replies:** 3\
**Last updated:** [January 7, 2025, 8:46am UTC](https://discourse.julialang.org/t/choosing-a-convention-for-complex-numbers-in-differentiationinterface/124433 "2025-01-07T08:46:17Z")

</div>

Hi everyone, As DifferentiationInterface.jl gains more traction, I find myself forced to confront the issue of AD with complex numbers. Right now they are not officially supported, but they should be and I wonder what t…

---

## [Unit tangent vector in Gridap.jl](https://discourse.julialang.org/t/unit-tangent-vector-in-gridap-jl/108181)

<div class="topic-metadata">

**Author:** [@andy45](https://discourse.julialang.org/u/andy45)\
**Replies:** 4\
**Last updated:** [January 7, 2025, 8:38am UTC](https://discourse.julialang.org/t/unit-tangent-vector-in-gridap-jl/108181 "2025-01-07T08:38:16Z")

</div>

Hi. I am trying to solve two-dimensional Stokes-Darcy equations using Gridap.jl. One of the terms in a weak formulation has the form {\\int\_{I}\\lambda\\left(u\\cdot\\tau\\right)\\left(v\\cdot\\tau\\right)ds} where \\tau is a unit …

---

## [Best practices for managing websocket/http server lifecycle](https://discourse.julialang.org/t/best-practices-for-managing-websocket-http-server-lifecycle/124434)

<div class="topic-metadata">

**Author:** [@danvinci](https://discourse.julialang.org/u/danvinci)\
**Replies:** 12\
**Last updated:** [January 7, 2025, 2:12am UTC](https://discourse.julialang.org/t/best-practices-for-managing-websocket-http-server-lifecycle/124434 "2025-01-07T02:12:24Z")

</div>

Hello folks! I’m experimenting with HTTP.jl and I’m trying to put in a place a watchdog task that would regularly check on the server, and spin up a new one if it goes down. The issue I’m encountering is that I get thi…

---

## [Using MathOptInterface.AbstractOptimizer in parametric type declaration](https://discourse.julialang.org/t/using-mathoptinterface-abstractoptimizer-in-parametric-type-declaration/124486)

<div class="topic-metadata">

**Author:** [@danrib07](https://discourse.julialang.org/u/danrib07)\
**Replies:** 1\
**Last updated:** [January 6, 2025, 11:40pm UTC](https://discourse.julialang.org/t/using-mathoptinterface-abstractoptimizer-in-parametric-type-declaration/124486 "2025-01-06T23:40:06Z")

</div>

Hi all, I have a question regarding using the MathOptInterface.AbstractOptimizer for parametric type declaration when defining a composite type. For example, take the type definition below: using JuMP # JuMP reexports …

---

## [ODE solving is fast on DifferentialEquation@7.9.0 but significantly slower on later versions](https://discourse.julialang.org/t/ode-solving-is-fast-on-differentialequation-7-9-0-but-significantly-slower-on-later-versions/124377)

<div class="topic-metadata">

**Author:** [@equi](https://discourse.julialang.org/u/equi)\
**Replies:** 10\
**Last updated:** [January 6, 2025, 10:12am UTC](https://discourse.julialang.org/t/ode-solving-is-fast-on-differentialequation-7-9-0-but-significantly-slower-on-later-versions/124377 "2025-01-06T10:12:14Z")

</div>

When solving the same ODE (a 100-dimensional strongly slow-fast system, where the non-smooth component is approximated using hyperbolic tangent function ) problem using DifferentialEquations.jl , I noticed that ODE solvi…

---

## [Note on eachindex behavior with GroupedDataFrame](https://discourse.julialang.org/t/note-on-eachindex-behavior-with-groupeddataframe/124439)

<div class="topic-metadata">

**Author:** [@George9000](https://discourse.julialang.org/u/George9000)\
**Replies:** 1\
**Last updated:** [January 5, 2025, 10:56am UTC](https://discourse.julialang.org/t/note-on-eachindex-behavior-with-groupeddataframe/124439 "2025-01-05T10:56:04Z")

</div>

eachindex used on a GroupedDataFrame, returns a GroupKey, such as GroupKey: (site = 'b',). When using the indices to create figure layouts in Makie or other plotting packages, (Axis(fig\[i, 1\]), one should explicitly ask…

---

## ["Quality of life" functions for CUDA.jl or GPUArrays.jl](https://discourse.julialang.org/t/quality-of-life-functions-for-cuda-jl-or-gpuarrays-jl/124220)

<div class="topic-metadata">

**Author:** [@anprasad](https://discourse.julialang.org/u/anprasad)\
**Replies:** 1\
**Last updated:** [January 5, 2025, 8:35am UTC](https://discourse.julialang.org/t/quality-of-life-functions-for-cuda-jl-or-gpuarrays-jl/124220 "2025-01-05T08:35:26Z")

</div>

First off, I want to thank the maintainers of JuliaGPU for the unbelievable work they’re doing. Even for someone like me who’s just beginning to write basic GPU kernels, it’s been easier and more illuminating to do so in…

---

## [How to define vector-valued @operator in JuMP](https://discourse.julialang.org/t/how-to-define-vector-valued-operator-in-jump/124438)

<div class="topic-metadata">

**Author:** [@Rick](https://discourse.julialang.org/u/Rick)\
**Replies:** 4\
**Last updated:** [January 5, 2025, 4:43am UTC](https://discourse.julialang.org/t/how-to-define-vector-valued-operator-in-jump/124438 "2025-01-05T04:43:07Z")

</div>

Hi, I am trying to solve a nonlinear model using JuMP. Part of the constraints come from the gradient of a nonlinear function. I am trying to compute it using ForwardDiff. As such, I need to define an operator and then …

---

## [How to exactly solve large overdetermined systems of linear equations](https://discourse.julialang.org/t/how-to-exactly-solve-large-overdetermined-systems-of-linear-equations/86710)

<div class="topic-metadata">

**Author:** [@nsajko](https://discourse.julialang.org/u/nsajko)\
**Replies:** 16\
**Last updated:** [January 4, 2025, 5:48pm UTC](https://discourse.julialang.org/t/how-to-exactly-solve-large-overdetermined-systems-of-linear-equations/86710 "2025-01-04T17:48:02Z")

</div>

Suppose I have, e.g., 250 linear equations with Rational{BigInt} coefficients, with 150 variables. If the system is inconsistent I want to know about it, otherwise I want the exact solution. Is there an easier way than …

---

## [How to save interactive plot with GLMakie](https://discourse.julialang.org/t/how-to-save-interactive-plot-with-glmakie/124352)

<div class="topic-metadata">

**Author:** [@Luigi\_Marongiu](https://discourse.julialang.org/u/Luigi_Marongiu)\
**Replies:** 5\
**Last updated:** [January 4, 2025, 3:15pm UTC](https://discourse.julialang.org/t/how-to-save-interactive-plot-with-glmakie/124352 "2025-01-04T15:15:10Z")

</div>

I am drawing an interactive plot with GLMakie that includes sliders. Is it possible to make a button to save the figure, preferably with the sliders or better with/without it? I can draw the button, but is there a simpl…

---

## [GLMakie LoadError when plotting contour](https://discourse.julialang.org/t/glmakie-loaderror-when-plotting-contour/124424)

<div class="topic-metadata">

**Author:** [@Jonas\_Bachmann](https://discourse.julialang.org/u/Jonas_Bachmann)\
**Replies:** 0\
**Last updated:** [January 4, 2025, 12:14pm UTC](https://discourse.julialang.org/t/glmakie-loaderror-when-plotting-contour/124424 "2025-01-04T12:14:41Z")

</div>

I am trying to make 3D contour plots in julia with GLMakie.jl. using GLMakie fig = Figure() ax = Axis3(fig\[1, 1\]) data = rand(30, 30, 30) surf = GLMakie.contour!(ax, data) save("fig.png", fig) When I run it, I get the…

---

## [Iterating through a continuous decision variable and retrieving its values](https://discourse.julialang.org/t/iterating-through-a-continuous-decision-variable-and-retrieving-its-values/124412)

<div class="topic-metadata">

**Author:** [@rolim.gustavo](https://discourse.julialang.org/u/rolim.gustavo)\
**Replies:** 4\
**Last updated:** [January 3, 2025, 5:29pm UTC](https://discourse.julialang.org/t/iterating-through-a-continuous-decision-variable-and-retrieving-its-values/124412 "2025-01-03T17:29:45Z")

</div>

Dear colleagues, I am implementing a branch-and-check procedure in JuMP that requires to extract some variable values. For instance, I have to retrieve the values of decision variable X, that is defined as follows: @va…

---

## [Qt Warning: \*path/to/file.qml\*: RangeError: Maximum call stack size exceeded](https://discourse.julialang.org/t/qt-warning-path-to-file-qml-rangeerror-maximum-call-stack-size-exceeded/122130)

<div class="topic-metadata">

**Author:** [@Valery](https://discourse.julialang.org/u/Valery)\
**Replies:** 7\
**Last updated:** [January 3, 2025, 1:31pm UTC](https://discourse.julialang.org/t/qt-warning-path-to-file-qml-rangeerror-maximum-call-stack-size-exceeded/122130 "2025-01-03T13:31:52Z")

</div>

When runing this using QML using Observables slidervalue = Observable(0.0) loadqml( joinpath(pwd(),"slider.qml"), variables = JuliaPropertyMap( "slidervalue" =\> slidervalue ) ) exec() and the content of “s…

---

## [How to select more than one object with Stipple.select()](https://discourse.julialang.org/t/how-to-select-more-than-one-object-with-stipple-select/124394)

<div class="topic-metadata">

**Author:** [@TheHedgehog2000](https://discourse.julialang.org/u/TheHedgehog2000)\
**Replies:** 1\
**Last updated:** [January 3, 2025, 12:34pm UTC](https://discourse.julialang.org/t/how-to-select-more-than-one-object-with-stipple-select/124394 "2025-01-03T12:34:10Z")

</div>

It’s straightforward using Stipple to select an object x from options y like Stipple.select(:x; options=:y) . Is there a way for x to be an array of options? More concretely, if y is an array of files that I’ve uploaded …

---

## [Using Knitro with ForwardDiff and JuMP](https://discourse.julialang.org/t/using-knitro-with-forwarddiff-and-jump/124396)

<div class="topic-metadata">

**Author:** [@Rick](https://discourse.julialang.org/u/Rick)\
**Replies:** 2\
**Last updated:** [January 3, 2025, 6:22am UTC](https://discourse.julialang.org/t/using-knitro-with-forwarddiff-and-jump/124396 "2025-01-03T06:22:22Z")

</div>

Hi, I am trying to use Knitro with JuMP which contains a constraint that imposes the gradient of a function to be 0. I want to compute the gradient using ForwardDiff. I found this can be done using Ipopt, but I cannot …

---

## [Update a Plotly chart in Pluto in response to a click?](https://discourse.julialang.org/t/update-a-plotly-chart-in-pluto-in-response-to-a-click/124382)

<div class="topic-metadata">

**Author:** [@Kirby\_Zhang](https://discourse.julialang.org/u/Kirby_Zhang)\
**Replies:** 2\
**Last updated:** [January 2, 2025, 9:57pm UTC](https://discourse.julialang.org/t/update-a-plotly-chart-in-pluto-in-response-to-a-click/124382 "2025-01-02T21:57:14Z")

</div>

I would like to highlight the point that was clicked in a Plotly chart, within a Pluto notebook. I understand that since Pluto doesn’t support WebIO, you cannot use PlotlyJS but must use PlutoPlotly. Based on a supplied …

---

## [Compute integral for DelaunayTriangulation.jl to be able to solve PDE with FiniteVolumeMethod.jl](https://discourse.julialang.org/t/compute-integral-for-delaunaytriangulation-jl-to-be-able-to-solve-pde-with-finitevolumemethod-jl/124310)

<div class="topic-metadata">

**Author:** [@B4rtel](https://discourse.julialang.org/u/B4rtel)\
**Replies:** 4\
**Last updated:** [January 2, 2025, 3:20pm UTC](https://discourse.julialang.org/t/compute-integral-for-delaunaytriangulation-jl-to-be-able-to-solve-pde-with-finitevolumemethod-jl/124310 "2025-01-02T15:20:13Z")

</div>

Hi :), I would like to solve a advection PDE of the form \\frac{\\partial}{\\partial t} f(x,t) = - \\nabla\_x \\cdot \\left(\\left(\\int \[\\phi(p\_1(x,y),\\phi(p\_2(x,y)\]\\odot (y-x) f(y,t) \\text{d} y\\right) f(x,t)\\right) for p\_a(x\_i…

---

## [Second order gradient with Lux, Zygote, CUDA, Enzyme](https://discourse.julialang.org/t/second-order-gradient-with-lux-zygote-cuda-enzyme/124301)

<div class="topic-metadata">

**Author:** [@Tomas\_Pevny](https://discourse.julialang.org/u/Tomas_Pevny)\
**Replies:** 12\
**Last updated:** [January 2, 2025, 2:48pm UTC](https://discourse.julialang.org/t/second-order-gradient-with-lux-zygote-cuda-enzyme/124301 "2025-01-02T14:48:04Z")

</div>

Dear All, I had a small pet project over the christmas, for some very specific application (steganography) I want to train a neural network while regularizing the gradient with respect to the input, which means that dur…

---

## [Unable to construct \`ADNLPModel\` with a matrix of linear constraints](https://discourse.julialang.org/t/unable-to-construct-adnlpmodel-with-a-matrix-of-linear-constraints/124361)

<div class="topic-metadata">

**Author:** [@ForceBru](https://discourse.julialang.org/u/ForceBru)\
**Replies:** 3\
**Last updated:** [January 2, 2025, 1:14pm UTC](https://discourse.julialang.org/t/unable-to-construct-adnlpmodel-with-a-matrix-of-linear-constraints/124361 "2025-01-02T13:14:04Z")

</div>

The documentation of ADNLPModels.ADNLPModel suggests that there are methods that accept a matrix A to signify linear constraints: ADNLPModel(f, x0, A, lcon, ucon) ADNLPModel(f, x0, lvar, uvar, A, lcon, ucon) These cons…

---

## [GeoStats.jl 2025 survey](https://discourse.julialang.org/t/geostats-jl-2025-survey/124362)

<div class="topic-metadata">

**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\
**Replies:** 0\
**Last updated:** [January 2, 2025, 12:21pm UTC](https://discourse.julialang.org/t/geostats-jl-2025-survey/124362 "2025-01-02T12:21:04Z")

</div>

---

## [How to use sol.retcode to catch ODE instability?](https://discourse.julialang.org/t/how-to-use-sol-retcode-to-catch-ode-instability/124274)

<div class="topic-metadata">

**Author:** [@Luigi\_Marongiu](https://discourse.julialang.org/u/Luigi_Marongiu)\
**Replies:** 3\
**Last updated:** [January 2, 2025, 10:08am UTC](https://discourse.julialang.org/t/how-to-use-sol-retcode-to-catch-ode-instability/124274 "2025-01-02T10:08:07Z")

</div>

I would like to make an interactive plot with GLMakie. There are some instances when the ODEs generate instability. I would like to plot a label “INSTABILITY DETECTED” in the plot itself when instability occurs. I under…

---

## [PowerModelsDistribution.jl defining new objective](https://discourse.julialang.org/t/powermodelsdistribution-jl-defining-new-objective/124269)

<div class="topic-metadata">

**Author:** [@Glon](https://discourse.julialang.org/u/Glon)\
**Replies:** 4\
**Last updated:** [January 1, 2025, 9:42pm UTC](https://discourse.julialang.org/t/powermodelsdistribution-jl-defining-new-objective/124269 "2025-01-01T21:42:50Z")

</div>

Hello all, What if I want to define a new objective for running OPF in PowerModelsDistribution.jl? How can I do this? If someone can share me an example, I would really appreciate it. Thank you!

---

## [Wind Rose 'hard' stacked barplot edges in GLMakie](https://discourse.julialang.org/t/wind-rose-hard-stacked-barplot-edges-in-glmakie/124277)

<div class="topic-metadata">

**Author:** [@ewillcox](https://discourse.julialang.org/u/ewillcox)\
**Replies:** 5\
**Last updated:** [January 1, 2025, 9:16pm UTC](https://discourse.julialang.org/t/wind-rose-hard-stacked-barplot-edges-in-glmakie/124277 "2025-01-01T21:16:52Z")

</div>

Hello, I am aiming to draw a wind rose similar to the below (from PlotlyJS.jl) in Makie. I can plot a stacked barplot into a PolarAxis: using GLMakie; using ColorSchemes; tbl = (cat = \[1, 1, 1, 2, 2, 2, 3, 3, 3\], …

---

## [SOCP and SDP solver errors in PowerModelsDistribution.jl](https://discourse.julialang.org/t/socp-and-sdp-solver-errors-in-powermodelsdistribution-jl/123945)

<div class="topic-metadata">

**Author:** [@Glon](https://discourse.julialang.org/u/Glon)\
**Replies:** 5\
**Last updated:** [January 1, 2025, 7:39pm UTC](https://discourse.julialang.org/t/socp-and-sdp-solver-errors-in-powermodelsdistribution-jl/123945 "2025-01-01T19:39:22Z")

</div>

Hello all, I am trying to use PowerModelsDistribution to solve a SDP and SOCP formulation. Below is my code. using PowerModelsDistribution using SCS Test\_Case = parse\_file(“C:/ACOPF/Julia/case3balancedbattery.dss”) …

---

## [Equivalence to add\_nonlinear\_constraint in new JuMP version](https://discourse.julialang.org/t/equivalence-to-add-nonlinear-constraint-in-new-jump-version/122901)

<div class="topic-metadata">

**Author:** [@VPBML](https://discourse.julialang.org/u/VPBML)\
**Replies:** 10\
**Last updated:** [December 31, 2024, 9:22pm UTC](https://discourse.julialang.org/t/equivalence-to-add-nonlinear-constraint-in-new-jump-version/122901 "2024-12-31T21:22:54Z")

</div>

Hi, I have used the functions add\_nonlinear\_constraint/ add\_nonlinear\_expression/ add\_nonlinear\_objective in the old version of JuMP to add programmatically-generated Expr objects to models. I wonder if these functions …

---

## [Recommendations for Julia Packages for FEA to be used in shape and topology optimization of 3D Shell Structures](https://discourse.julialang.org/t/recommendations-for-julia-packages-for-fea-to-be-used-in-shape-and-topology-optimization-of-3d-shell-structures/124270)

<div class="topic-metadata">

**Author:** [@Edan\_Lazerson](https://discourse.julialang.org/u/Edan_Lazerson)\
**Replies:** 6\
**Last updated:** [December 31, 2024, 6:57pm UTC](https://discourse.julialang.org/t/recommendations-for-julia-packages-for-fea-to-be-used-in-shape-and-topology-optimization-of-3d-shell-structures/124270 "2024-12-31T18:57:55Z")

</div>

Hello everyone, I’m working on my master’s project, which involves shape and topology optimization for a 3D shell structure. Initially, I plan to work within the linear static regime. Instead of writing my own finite el…

---

## [Is it possible to join two dataframes that returns a view of the original two?](https://discourse.julialang.org/t/is-it-possible-to-join-two-dataframes-that-returns-a-view-of-the-original-two/124296)

<div class="topic-metadata">

**Author:** [@okatsn](https://discourse.julialang.org/u/okatsn)\
**Replies:** 1\
**Last updated:** [December 31, 2024, 2:36am UTC](https://discourse.julialang.org/t/is-it-possible-to-join-two-dataframes-that-returns-a-view-of-the-original-two/124296 "2024-12-31T02:36:32Z")

</div>

In julia programming, is it possible to join two dataframes, where the joined dataframe is essentially a “view” of the original two? For example, julia\> name = DataFrame(ID=\[1, 2, 3\], Name=\["John Doe", "Jane Doe", "J…

---

## [Feasibility Inquiry: Building a Chemical Process Simulation and Optimization Package with JuMP](https://discourse.julialang.org/t/feasibility-inquiry-building-a-chemical-process-simulation-and-optimization-package-with-jump/109236)

<div class="topic-metadata">

**Author:** [@JackaChou](https://discourse.julialang.org/u/JackaChou)\
**Replies:** 44\
**Last updated:** [December 30, 2024, 3:56am UTC](https://discourse.julialang.org/t/feasibility-inquiry-building-a-chemical-process-simulation-and-optimization-package-with-jump/109236 "2024-12-30T03:56:21Z")

</div>

I am a user of JuMP and am aware that the Institute for the Design of Advanced Energy Systems (IDAES) is a recently developed tool built on Python that utilizes the Pyomo optimization modeling language (https://doi.org/…

---

## [Clp: 0 dependencies successfully precompiled in 4 seconds. 107 already precompiled](https://discourse.julialang.org/t/clp-0-dependencies-successfully-precompiled-in-4-seconds-107-already-precompiled/124148)

<div class="topic-metadata">

**Author:** [@anonymous\_user](https://discourse.julialang.org/u/anonymous_user)\
**Replies:** 8\
**Last updated:** [December 29, 2024, 11:09pm UTC](https://discourse.julialang.org/t/clp-0-dependencies-successfully-precompiled-in-4-seconds-107-already-precompiled/124148 "2024-12-29T23:09:39Z")

</div>

Help I cannot fix this on my Macbook julia\> Pkg.add(“Clp”) Resolving package versions… No Changes to ~/.julia/environments/v1.11/Project.toml No Changes to ~/.julia/environments/v1.11/Manifest.toml Precompiling proj…

---

## [Recommended workflow for map combining topography and street network](https://discourse.julialang.org/t/recommended-workflow-for-map-combining-topography-and-street-network/124208)

<div class="topic-metadata">

**Author:** [@fa-bien](https://discourse.julialang.org/u/fa-bien)\
**Replies:** 8\
**Last updated:** [December 29, 2024, 11:41am UTC](https://discourse.julialang.org/t/recommended-workflow-for-map-combining-topography-and-street-network/124208 "2024-12-29T11:41:51Z")

</div>

I want to plot what I imagine (perhaps naively) to be a simple map, combining a topographic layer and the street network, for a small geographic area (one city district). I believe I cannot use an already-existing layer …

[Previous page](https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=63)

[Next page](https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=65)