# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=222

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

**Page:** 223

---

## [Question about applying a customized branch and bound in Julia and the JuMP package](https://discourse.julialang.org/t/question-about-applying-a-customized-branch-and-bound-in-julia-and-the-jump-package/93136)

<div class="topic-metadata">

**Author:** [@Alex\_ricci](https://discourse.julialang.org/u/Alex_ricci)\
**Replies:** 3\
**Last updated:** [January 19, 2023, 2:34am UTC](https://discourse.julialang.org/t/question-about-applying-a-customized-branch-and-bound-in-julia-and-the-jump-package/93136 "2023-01-19T02:34:08Z")

</div>

I am trying to develop a customised branch and bound algorithm in Julia with the JuMP package. The problem only has binary variables. What I do is relaxing the problem to its linear counterpart and getting the variable …

---

## [Anybody know why this error occurs when trying to define a Catalyst @reaction\_network in Jupyter Notebooks?](https://discourse.julialang.org/t/anybody-know-why-this-error-occurs-when-trying-to-define-a-catalyst-reaction-network-in-jupyter-notebooks/93119)

<div class="topic-metadata">

**Author:** [@jonathanfischer97](https://discourse.julialang.org/u/jonathanfischer97)\
**Replies:** 4\
**Last updated:** [January 19, 2023, 2:19am UTC](https://discourse.julialang.org/t/anybody-know-why-this-error-occurs-when-trying-to-define-a-catalyst-reaction-network-in-jupyter-notebooks/93119 "2023-01-19T02:19:35Z")

</div>

---

## [ForwardDiff AD Error using distributed within Turing @model](https://discourse.julialang.org/t/forwarddiff-ad-error-using-distributed-within-turing-model/93111)

<div class="topic-metadata">

**Author:** [@abhishek-venket](https://discourse.julialang.org/u/abhishek-venket)\
**Replies:** 0\
**Last updated:** [January 17, 2023, 7:17pm UTC](https://discourse.julialang.org/t/forwarddiff-ad-error-using-distributed-within-turing-model/93111 "2023-01-17T19:17:00Z")

</div>

I am trying to estimate the posterior distributions of a couple of parameters of a system of ODEs. The probabilistic model is data ~ MvNormal(y\_sim, σ² \* I), where data contains sensor measurements of a quantity of inte…

---

## [Stochastic (L-)BFGS](https://discourse.julialang.org/t/stochastic-l-bfgs/93138)

<div class="topic-metadata">

**Author:** [@jbrea](https://discourse.julialang.org/u/jbrea)\
**Replies:** 1\
**Last updated:** [January 18, 2023, 4:33pm UTC](https://discourse.julialang.org/t/stochastic-l-bfgs/93138 "2023-01-18T16:33:26Z")

</div>

Anyone knows of a julia implementation of a stochastic (L-)BFGS variant, like e.g. described here or described here or implemented in pytorch here?

---

## [Poincare map DifferentialEquations.jl](https://discourse.julialang.org/t/poincare-map-differentialequations-jl/92308)

<div class="topic-metadata">

**Author:** [@Sergey\_Novak](https://discourse.julialang.org/u/Sergey_Novak)\
**Replies:** 14\
**Last updated:** [January 18, 2023, 9:02am UTC](https://discourse.julialang.org/t/poincare-map-differentialequations-jl/92308 "2023-01-18T09:02:24Z")

</div>

Hello, i have system: function model(u, p ,t) E, x, u\_, y = u τ, α, τ\_D, J, U0, ΔU0, τ\_y, β, xthr, ythr, I0 = p U(y, U0, ΔU0, ythr) = U0 + ΔU0 / ( 1 + exp( -50 \* ( y - ythr ) ) ) σ(x, xthr)= 1 …

---

## [Use of linear operators on a GPU](https://discourse.julialang.org/t/use-of-linear-operators-on-a-gpu/92899)

<div class="topic-metadata">

**Author:** [@shakedregev](https://discourse.julialang.org/u/shakedregev)\
**Replies:** 3\
**Last updated:** [January 18, 2023, 7:12am UTC](https://discourse.julialang.org/t/use-of-linear-operators-on-a-gpu/92899 "2023-01-18T07:12:19Z")

</div>

Say I have a sparse matrices $A$ and $B=D\*A^T$ and their product is dense. I want to solve systems with them using an iterative method from Krylov.jl. On a CPU, I can do opC =LinearOperator(A)\*LinearOperator(B) cg(opC,…

---

## [Raw file streaming read for SampledSignals](https://discourse.julialang.org/t/raw-file-streaming-read-for-sampledsignals/93125)

<div class="topic-metadata">

**Author:** [@minetest2048](https://discourse.julialang.org/u/minetest2048)\
**Replies:** 0\
**Last updated:** [January 18, 2023, 3:57am UTC](https://discourse.julialang.org/t/raw-file-streaming-read-for-sampledsignals/93125 "2023-01-18T03:57:54Z")

</div>

Is there a package where it implements something like GitHub - JuliaAudio/LibSndFile.jl: Julia Interface to libsndfile but with raw file, something like stream = loadstreaming("myfile.raw";format=Complex{Float32},n\_chan…

---

## [How to format sequential data to be used in reccurence models when batches are needed?](https://discourse.julialang.org/t/how-to-format-sequential-data-to-be-used-in-reccurence-models-when-batches-are-needed/93060)

<div class="topic-metadata">

**Author:** [@mantzaris](https://discourse.julialang.org/u/mantzaris)\
**Replies:** 6\
**Last updated:** [January 18, 2023, 2:23am UTC](https://discourse.julialang.org/t/how-to-format-sequential-data-to-be-used-in-reccurence-models-when-batches-are-needed/93060 "2023-01-18T02:23:40Z")

</div>

What is the best (recommended) way to store sequence data for recurrence models in Flux when it is aimed to be used in ‘batches’? At the moment I store the X data (features) as onehot hot encoded where the features span …

---

## [Deep Reinforcement Learning](https://discourse.julialang.org/t/deep-reinforcement-learning/93104)

<div class="topic-metadata">

**Author:** [@DFKMB](https://discourse.julialang.org/u/DFKMB)\
**Replies:** 1\
**Last updated:** [January 17, 2023, 6:50pm UTC](https://discourse.julialang.org/t/deep-reinforcement-learning/93104 "2023-01-17T18:50:11Z")

</div>

Are there any libraries for Deep Reinforcement Learning in Julia that have cover PPOs and DDPMs as they relate to finance? If so, I have a follow up question.

---

## [Hiring Quantum Information Science Julia programmers (cross-post)](https://discourse.julialang.org/t/hiring-quantum-information-science-julia-programmers-cross-post/93098)

<div class="topic-metadata">

**Author:** [@Krastanov](https://discourse.julialang.org/u/Krastanov)\
**Replies:** 0\
**Last updated:** [January 17, 2023, 2:28pm UTC](https://discourse.julialang.org/t/hiring-quantum-information-science-julia-programmers-cross-post/93098 "2023-01-17T14:28:48Z")

</div>

A cross-post for the Julia Quantum hackers that do not peruse the job board of this forum. We (The NSF Center for Quantum Networks and UMass Amherst) are hiring people interested in high-fidelity simulations of quantum …

---

## [Makie.jl Export with transparent background](https://discourse.julialang.org/t/makie-jl-export-with-transparent-background/93087)

<div class="topic-metadata">

**Author:** [@Kevin\_Kleinbeck](https://discourse.julialang.org/u/Kevin_Kleinbeck)\
**Replies:** 1\
**Last updated:** [January 17, 2023, 1:52pm UTC](https://discourse.julialang.org/t/makie-jl-export-with-transparent-background/93087 "2023-01-17T13:52:19Z")

</div>

I have a high resolution dataset, about 1000x1000 points for which I want to export the surface plot, like in fig = Figure(resolution = (1000, 1300), figure\_padding = (0, 26, 2, 0)) axis = Axis3(fig\[1, 1\], azimuth = π…

---

## [Unable to use InteractiveDynamics and Agents as Part of my Package](https://discourse.julialang.org/t/unable-to-use-interactivedynamics-and-agents-as-part-of-my-package/78265)

<div class="topic-metadata">

**Author:** [@codekomali](https://discourse.julialang.org/u/codekomali)\
**Replies:** 18\
**Last updated:** [January 17, 2023, 12:56pm UTC](https://discourse.julialang.org/t/unable-to-use-interactivedynamics-and-agents-as-part-of-my-package/78265 "2023-01-17T12:56:55Z")

</div>

I am trying to use the latest InteractiveDynamics v0.20 and Agents v5.0 as part of my project. Since yesterday, I am getting the following error, whenever I try to precompile my package. ERROR: LoadError: UndefVarError:…

---

## [Add agent to random position in 3D GridSpace](https://discourse.julialang.org/t/add-agent-to-random-position-in-3d-gridspace/92847)

<div class="topic-metadata">

**Author:** [@sea\_slug](https://discourse.julialang.org/u/sea_slug)\
**Replies:** 4\
**Last updated:** [January 17, 2023, 12:47pm UTC](https://discourse.julialang.org/t/add-agent-to-random-position-in-3d-gridspace/92847 "2023-01-17T12:47:24Z")

</div>

I am trying to create a 3D ABM using agents.jl. I am stuck with a very simple issue, I cannot add agents to the GridSpace. I just want to give each agent a random starting point in 3D space. I have cannibalised the wolf…

---

## [Flux on gpu and inference optimization](https://discourse.julialang.org/t/flux-on-gpu-and-inference-optimization/93016)

<div class="topic-metadata">

**Author:** [@Fabrice\_Rosay](https://discourse.julialang.org/u/Fabrice_Rosay)\
**Replies:** 2\
**Last updated:** [January 17, 2023, 7:38am UTC](https://discourse.julialang.org/t/flux-on-gpu-and-inference-optimization/93016 "2023-01-17T07:38:59Z")

</div>

Hi, I’m currently running an Alphazero replica with Flux. As you may know most of the time is spent during selfplay and essentially doing neural network inferences. I’m currently using a batchsize of 512 and when mesuri…

---

## [Aligning Multi-line Text (in Makie)](https://discourse.julialang.org/t/aligning-multi-line-text-in-makie/93012)

<div class="topic-metadata">

**Author:** [@Whyborn](https://discourse.julialang.org/u/Whyborn)\
**Replies:** 2\
**Last updated:** [January 17, 2023, 4:44am UTC](https://discourse.julialang.org/t/aligning-multi-line-text-in-makie/93012 "2023-01-17T04:44:32Z")

</div>

Hi, Is it possible to do multiline text alignment in Makie plots LaTeX equation style? For example, describing some fluid conditions, I would like to write text something like: text!(ax, location, text = "p=100kPa\\nT=3…

---

## [Axis labels in makie.jl 3d plots](https://discourse.julialang.org/t/axis-labels-in-makie-jl-3d-plots/93050)

<div class="topic-metadata">

**Author:** [@math\_opt](https://discourse.julialang.org/u/math_opt)\
**Replies:** 0\
**Last updated:** [January 16, 2023, 9:19pm UTC](https://discourse.julialang.org/t/axis-labels-in-makie-jl-3d-plots/93050 "2023-01-16T21:19:42Z")

</div>

I have a very basic question about plotting 3D data using Makie.jl. How to set the axes labels? An MWE is provided below: using CairoMakie using Random fig = scatter(rand(10), rand(10), rand(10)) xlabel!("label-1") yl…

---

## [Creating a Binary Vector from a ZIP File](https://discourse.julialang.org/t/creating-a-binary-vector-from-a-zip-file/93044)

<div class="topic-metadata">

**Author:** [@maxstb11](https://discourse.julialang.org/u/maxstb11)\
**Replies:** 0\
**Last updated:** [January 16, 2023, 7:42pm UTC](https://discourse.julialang.org/t/creating-a-binary-vector-from-a-zip-file/93044 "2023-01-16T19:42:28Z")

</div>

Hello everyone, I have an Issue getting the correct binary Vector of a ZIP File when using the Package ZipFile.jl I want to use the GoogleCloud.jl Package to upload a zip file. Since the insert method only allows to pa…

---

## [Defining a history function for Delay Differential Equations using past data points](https://discourse.julialang.org/t/defining-a-history-function-for-delay-differential-equations-using-past-data-points/92935)

<div class="topic-metadata">

**Author:** [@tom-plaa](https://discourse.julialang.org/u/tom-plaa)\
**Replies:** 3\
**Last updated:** [January 16, 2023, 3:52pm UTC](https://discourse.julialang.org/t/defining-a-history-function-for-delay-differential-equations-using-past-data-points/92935 "2023-01-16T15:52:58Z")

</div>

I was trying to figure out how to define delay differential equations using DifferentialEquations.jl, but even after reading through the documentation, I am somewhat confused on how to define the history function. I am s…

---

## [Extracting ODEProblem formulas and passing them to JuMP NLExpressions](https://discourse.julialang.org/t/extracting-odeproblem-formulas-and-passing-them-to-jump-nlexpressions/92910)

<div class="topic-metadata">

**Author:** [@zornsllama](https://discourse.julialang.org/u/zornsllama)\
**Replies:** 4\
**Last updated:** [January 16, 2023, 3:52pm UTC](https://discourse.julialang.org/t/extracting-odeproblem-formulas-and-passing-them-to-jump-nlexpressions/92910 "2023-01-16T15:52:21Z")

</div>

I am trying to write a code that extracts a model’s equations from a DiffEq.jl ODEProblem or ModelingToolkit.jl ODESystem and copies them into JuMP.jl NLExpressions for use in nonlinear programming. In particular, I need…

---

## [SVD on a matrix that does not fit into memory](https://discourse.julialang.org/t/svd-on-a-matrix-that-does-not-fit-into-memory/92802)

<div class="topic-metadata">

**Author:** [@aasdelat](https://discourse.julialang.org/u/aasdelat)\
**Replies:** 20\
**Last updated:** [January 16, 2023, 3:44pm UTC](https://discourse.julialang.org/t/svd-on-a-matrix-that-does-not-fit-into-memory/92802 "2023-01-16T15:44:17Z")

</div>

I am looking for a function that makes a SVD on a matrix that does not fit into memory. I am interested in using just one computer, although an answer for a cluster can be useful for other users. The python dask package…

---

## [3 yaxes with Makie?](https://discourse.julialang.org/t/3-yaxes-with-makie/93032)

<div class="topic-metadata">

**Author:** [@ohmsweetohm1](https://discourse.julialang.org/u/ohmsweetohm1)\
**Replies:** 1\
**Last updated:** [January 16, 2023, 3:42pm UTC](https://discourse.julialang.org/t/3-yaxes-with-makie/93032 "2023-01-16T15:42:36Z")

</div>

Is it possible to make 3 or more y-axes with Makie.jl? You can plot the data but how to move the spines? fig=Figure() ax11 = Axis(fig\[1,1\], ylabel="Series 1") lines!(cumsum(randn(1000))) ax12 = Axis(fig\[1,1\], yticklabel…

---

## [How do I make sure that GPU functions use the maximum potential config for performance?](https://discourse.julialang.org/t/how-do-i-make-sure-that-gpu-functions-use-the-maximum-potential-config-for-performance/92989)

<div class="topic-metadata">

**Author:** [@Ahmed\_Salih](https://discourse.julialang.org/u/Ahmed_Salih)\
**Replies:** 3\
**Last updated:** [January 16, 2023, 3:13pm UTC](https://discourse.julialang.org/t/how-do-i-make-sure-that-gpu-functions-use-the-maximum-potential-config-for-performance/92989 "2023-01-16T15:13:07Z")

</div>

Hello! I am doing some programming on GPU using CUDA. Instead of writing kernels I am doing the recommended approach of using commonly available functions for GPU programming in CUDA.jl such as “.”, “map” etc. I notic…

---

## ["x" Argument in Optimization.OptimizationProblem](https://discourse.julialang.org/t/x-argument-in-optimization-optimizationproblem/92971)

<div class="topic-metadata">

**Author:** [@jonlym](https://discourse.julialang.org/u/jonlym)\
**Replies:** 1\
**Last updated:** [January 16, 2023, 3:49am UTC](https://discourse.julialang.org/t/x-argument-in-optimization-optimizationproblem/92971 "2023-01-16T03:49:48Z")

</div>

The docs for Optimization.OptimizationProblem refer to u and u₀ but neither are included in the argument list. Should the second positional argument (i.e., x) be relabeled to u? If they’re not representing the same thing…

---

## [Numerically stable derivative of logerf without catastrophic cancellation](https://discourse.julialang.org/t/numerically-stable-derivative-of-logerf-without-catastrophic-cancellation/92992)

<div class="topic-metadata">

**Author:** [@user22](https://discourse.julialang.org/u/user22)\
**Replies:** 4\
**Last updated:** [January 15, 2023, 4:56pm UTC](https://discourse.julialang.org/t/numerically-stable-derivative-of-logerf-without-catastrophic-cancellation/92992 "2023-01-15T16:56:08Z")

</div>

I need to evaluate the derivative of a logerf function fun with respect to x within the widest possible range of x. At the moment, the derivative is calculated through the function dfun. using LogExpFunctions using Fini…

---

## [How to use data for training and tests with glm?](https://discourse.julialang.org/t/how-to-use-data-for-training-and-tests-with-glm/92928)

<div class="topic-metadata">

**Author:** [@jcbritobr](https://discourse.julialang.org/u/jcbritobr)\
**Replies:** 5\
**Last updated:** [January 13, 2023, 5:07pm UTC](https://discourse.julialang.org/t/how-to-use-data-for-training-and-tests-with-glm/92928 "2023-01-13T17:07:07Z")

</div>

Hello, good morning. I’m having troubles to separate and use my data for training and tests with glm. Once I have tests and training data, I had fit my model with train data, but can’t understand how to predic with my t…

---

## [How to capture model output with loss in Flux.withgradient](https://discourse.julialang.org/t/how-to-capture-model-output-with-loss-in-flux-withgradient/92766)

<div class="topic-metadata">

**Author:** [@reachtarunhere](https://discourse.julialang.org/u/reachtarunhere)\
**Replies:** 3\
**Last updated:** [January 13, 2023, 2:54pm UTC](https://discourse.julialang.org/t/how-to-capture-model-output-with-loss-in-flux-withgradient/92766 "2023-01-13T14:54:59Z")

</div>

Here is the sample code for my training loop function train() @showprogress for i in 1:10 l, grads = Flux.withgradient(m -\> lossfn(m(X), Y), model) fmap(model, grads\[1\]) do p, g p .= p .-…

---

## [MySQL Connection closes when writing to database from multiple workers](https://discourse.julialang.org/t/mysql-connection-closes-when-writing-to-database-from-multiple-workers/92916)

<div class="topic-metadata">

**Author:** [@SanAlphaTau](https://discourse.julialang.org/u/SanAlphaTau)\
**Replies:** 1\
**Last updated:** [January 13, 2023, 2:26pm UTC](https://discourse.julialang.org/t/mysql-connection-closes-when-writing-to-database-from-multiple-workers/92916 "2023-01-13T14:26:12Z")

</div>

Heya, I am trying to write data generated by a compute intensive function into a database for storage and later analysis. I have been trying to use MySQL.jl to manage the connection. I am running into an issue where wh…

---

## [Machine Learning Classification](https://discourse.julialang.org/t/machine-learning-classification/92915)

<div class="topic-metadata">

**Author:** [@BadBoy](https://discourse.julialang.org/u/BadBoy)\
**Replies:** 3\
**Last updated:** [January 13, 2023, 1:41pm UTC](https://discourse.julialang.org/t/machine-learning-classification/92915 "2023-01-13T13:41:27Z")

</div>

How can I find the best subset of the predictors for a classification problem?? Any kind of help will be appreciated. Thanks in advance.

---

## [\`twiny\` in Plots somehow break the subplot margin](https://discourse.julialang.org/t/twiny-in-plots-somehow-break-the-subplot-margin/92901)

<div class="topic-metadata">

**Author:** [@babaq](https://discourse.julialang.org/u/babaq)\
**Replies:** 0\
**Last updated:** [January 12, 2023, 11:53pm UTC](https://discourse.julialang.org/t/twiny-in-plots-somehow-break-the-subplot-margin/92901 "2023-01-12T23:53:15Z")

</div>

Hi, For a subplot to have tight margins, i did this and plot looks fine. p=plot(layout=(1,3),leg=false) for i in 1:3 leftmargin = i==1 ? 6Plots.mm : -4Plots.mm heatmap!(p\[i\],rand(10,10),yticks=\[\];leftmargin) en…

---

## [Gurobi- failed to precompile](https://discourse.julialang.org/t/gurobi-failed-to-precompile/44606)

<div class="topic-metadata">

**Author:** [@MJMB](https://discourse.julialang.org/u/MJMB)\
**Replies:** 9\
**Last updated:** [January 13, 2023, 4:47am UTC](https://discourse.julialang.org/t/gurobi-failed-to-precompile/44606 "2023-01-13T04:47:40Z")

</div>

Hello, I have problem with gurobi, i am using MacBook Pro and suddenly it show me error that it failed to precompile, i have tried to remove it and add it again but it doesn’t work. my license is valid and i am using G…

[Previous page](https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=221)

[Next page](https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=223)