# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1132

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

**Page:** 1133

---

## [Using Custom Structs for Nonlinear Optimization](https://discourse.julialang.org/t/using-custom-structs-for-nonlinear-optimization/75755)

<div class="topic-metadata">

**Author:** [@danny.s](https://discourse.julialang.org/u/danny.s)\
**Replies:** 1\
**Last updated:** [February 3, 2022, 10:35pm UTC](https://discourse.julialang.org/t/using-custom-structs-for-nonlinear-optimization/75755 "2022-02-03T22:35:55Z")

</div>

Hi, I’m new to JuMP and I’m trying to wrap my head around why what I’m doing is incorrect. A much simplified MWE is below: using JuMP, Ipopt M,N = 3,5 struct myPoly vec end function (f::myPoly)(x) ret = 0. …

---

## [Trouble Accessing Minimizer from Optim](https://discourse.julialang.org/t/trouble-accessing-minimizer-from-optim/75763)

<div class="topic-metadata">

**Author:** [@as2022](https://discourse.julialang.org/u/as2022)\
**Replies:** 2\
**Last updated:** [February 3, 2022, 9:37pm UTC](https://discourse.julialang.org/t/trouble-accessing-minimizer-from-optim/75763 "2022-02-03T21:37:28Z")

</div>

Hi All, I am new to Julia and I am using the Optim package for the first time. The optimize function seems to be finding a solution to my problem, but I cannot figure out how to access the solution. All I see is the obj…

---

## [Debugging in VS Code takes long time to start and then Stuck for julia code?](https://discourse.julialang.org/t/debugging-in-vs-code-takes-long-time-to-start-and-then-stuck-for-julia-code/75753)

<div class="topic-metadata">

**Author:** [@Amro](https://discourse.julialang.org/u/Amro)\
**Replies:** 0\
**Last updated:** [February 3, 2022, 8:11pm UTC](https://discourse.julialang.org/t/debugging-in-vs-code-takes-long-time-to-start-and-then-stuck-for-julia-code/75753 "2022-02-03T20:11:18Z")

</div>

I was using Run and Debug in VS code of my julia code normally. Just today, when I click on the debug, it takes almost 5 minutes to start and then I click continue, it freezes and then finish the debugging. I am wonderin…

---

## [Understanding an argument-modifying function](https://discourse.julialang.org/t/understanding-an-argument-modifying-function/75760)

<div class="topic-metadata">

**Author:** [@wub7quxa](https://discourse.julialang.org/u/wub7quxa)\
**Replies:** 2\
**Last updated:** [February 3, 2022, 9:10pm UTC](https://discourse.julialang.org/t/understanding-an-argument-modifying-function/75760 "2022-02-03T21:10:39Z")

</div>

I am using NLsolve to solve systems of nonlinear equations. Everything works fine, but I want to understand what this function does: function f!(F, x) F\[1\]=x\[1\]^2+3\*x\[2\]^2-9 F\[2\]=17\*x\[2\]-14\*x\[1\]^2+49 end f! app…

---

## [Is there a way to compile interactive tables into an HTML book in Julia?](https://discourse.julialang.org/t/is-there-a-way-to-compile-interactive-tables-into-an-html-book-in-julia/75533)

<div class="topic-metadata">

**Author:** [@WileyQuixotey](https://discourse.julialang.org/u/WileyQuixotey)\
**Replies:** 16\
**Last updated:** [February 3, 2022, 8:54pm UTC](https://discourse.julialang.org/t/is-there-a-way-to-compile-interactive-tables-into-an-html-book-in-julia/75533 "2022-02-03T20:54:29Z")

</div>

My lab uses HTML notebooks to communicate information to stakeholders. I am curious about migrating my workflow from R to Julia but am having trouble replicating an interactive table that I can include in the book like D…

---

## [Stipple with Oracle and Intersystems IRIS?](https://discourse.julialang.org/t/stipple-with-oracle-and-intersystems-iris/75751)

<div class="topic-metadata">

**Author:** [@bww00](https://discourse.julialang.org/u/bww00)\
**Replies:** 4\
**Last updated:** [February 3, 2022, 8:52pm UTC](https://discourse.julialang.org/t/stipple-with-oracle-and-intersystems-iris/75751 "2022-02-03T20:52:41Z")

</div>

Looking for an update on Stipple Thanks

---

## [CUDA AES implementation help: Parallelizing execution on Array{UInt8, 16} type inputs](https://discourse.julialang.org/t/cuda-aes-implementation-help-parallelizing-execution-on-array-uint8-16-type-inputs/75732)

<div class="topic-metadata">

**Author:** [@Nightshade\_Lemonade](https://discourse.julialang.org/u/Nightshade_Lemonade)\
**Replies:** 6\
**Last updated:** [February 3, 2022, 8:13pm UTC](https://discourse.julialang.org/t/cuda-aes-implementation-help-parallelizing-execution-on-array-uint8-16-type-inputs/75732 "2022-02-03T20:13:37Z")

</div>

I’m trying to do AES on the GPU. My latest attempt looks something like this: # AES has a similar function signature to this function blockAdd(b::Array{UInt8, 16})::Array{UInt8, 16} a = UInt8\[0 for i in 1:16\] fo…

---

## [Looping over previous row efficiency](https://discourse.julialang.org/t/looping-over-previous-row-efficiency/75749)

<div class="topic-metadata">

**Author:** [@korilium](https://discourse.julialang.org/u/korilium)\
**Replies:** 1\
**Last updated:** [February 3, 2022, 7:56pm UTC](https://discourse.julialang.org/t/looping-over-previous-row-efficiency/75749 "2022-02-03T19:56:14Z")

</div>

So I have a dataset with all stock prices and i want to compute the returns. I have done this the following way: test = copy(dollar\_portfolio) returns = copy(dollar\_portfolio\[2:end,:\]) @time for column in 2:length(doll…

---

## [Can I use Makie.jl without GPU](https://discourse.julialang.org/t/can-i-use-makie-jl-without-gpu/75590)

<div class="topic-metadata">

**Author:** [@matic\_lauko](https://discourse.julialang.org/u/matic_lauko)\
**Replies:** 5\
**Last updated:** [February 3, 2022, 8:01pm UTC](https://discourse.julialang.org/t/can-i-use-makie-jl-without-gpu/75590 "2022-02-03T20:01:55Z")

</div>

Hello, I’m trying to build an interactive graph, but I don’t have a GPU on my computer, can I still use Makie.jl. If not what would you recommend? Thank you for your help!

---

## [Dictionary use and assignment](https://discourse.julialang.org/t/dictionary-use-and-assignment/75746)

<div class="topic-metadata">

**Author:** [@Tominapa](https://discourse.julialang.org/u/Tominapa)\
**Replies:** 3\
**Last updated:** [February 3, 2022, 7:54pm UTC](https://discourse.julialang.org/t/dictionary-use-and-assignment/75746 "2022-02-03T19:54:02Z")

</div>

I have a question related to dictionary initialization. The code snippet illustrates the problem: function DictGen(KeyList, InitVal) return Dict(i =\> InitVal for i in collect(Iterators.product(KeyList...))) end # m…

---

## [Getting Allocations with Static Arrays](https://discourse.julialang.org/t/getting-allocations-with-static-arrays/75744)

<div class="topic-metadata">

**Author:** [@TI36XPro](https://discourse.julialang.org/u/TI36XPro)\
**Replies:** 5\
**Last updated:** [February 3, 2022, 6:49pm UTC](https://discourse.julialang.org/t/getting-allocations-with-static-arrays/75744 "2022-02-03T18:49:32Z")

</div>

Hello, I am trying to optimize some code and have some questions on behavior I am observing related to static arrays. I have read that if you have lots of small arrays (less than 100 elements) then static arrays are on…

---

## [Edit .NL files using JuMP](https://discourse.julialang.org/t/edit-nl-files-using-jump/75712)

<div class="topic-metadata">

**Author:** [@Luca](https://discourse.julialang.org/u/Luca)\
**Replies:** 1\
**Last updated:** [February 3, 2022, 5:41pm UTC](https://discourse.julialang.org/t/edit-nl-files-using-jump/75712 "2022-02-03T17:41:09Z")

</div>

Dear all, I would like to run a solvers comparison on several instances of MINLPLib. I can get the .NL files for each instance. Now, I would like to reformulate several instances and I need to edit the .NL files (in par…

---

## [Symlink can not create hardlink in windows10](https://discourse.julialang.org/t/symlink-can-not-create-hardlink-in-windows10/75702)

<div class="topic-metadata">

**Author:** [@babaq](https://discourse.julialang.org/u/babaq)\
**Replies:** 2\
**Last updated:** [February 3, 2022, 5:37pm UTC](https://discourse.julialang.org/t/symlink-can-not-create-hardlink-in-windows10/75702 "2022-02-03T17:37:31Z")

</div>

I tried mklink link target and mklink \\h link target in windows CMD, and it works fine. But when using symlink(target, link), it always creates soft link regardless of absolute/relative path. Is anyone have similar exp…

---

## [Using multiple index variables in Turing model](https://discourse.julialang.org/t/using-multiple-index-variables-in-turing-model/75743)

<div class="topic-metadata">

**Author:** [@ewcrombe](https://discourse.julialang.org/u/ewcrombe)\
**Replies:** 0\
**Last updated:** [February 3, 2022, 5:33pm UTC](https://discourse.julialang.org/t/using-multiple-index-variables-in-turing-model/75743 "2022-02-03T17:33:40Z")

</div>

Hello everyone, I would like to use two index variables in a model, but I don’t know how to do it… I would like to do something like this: @model function m2(A, G, D) α ~ MvNormal(\[\[0 0\] \[0 0\]\], …

---

## [Artifact from file rather than url](https://discourse.julialang.org/t/artifact-from-file-rather-than-url/75737)

<div class="topic-metadata">

**Author:** [@pizza](https://discourse.julialang.org/u/pizza)\
**Replies:** 1\
**Last updated:** [February 3, 2022, 5:20pm UTC](https://discourse.julialang.org/t/artifact-from-file-rather-than-url/75737 "2022-02-03T17:20:32Z")

</div>

Hi all, Trying to add OhMyREPL in my Windows setup at work fails because of artifact fzf. After some investigation, it turned out my company firewall blocks anything binary. Proxy environment variables are properly con…

---

## [Can I change my username so that it matches my GitHub username?](https://discourse.julialang.org/t/can-i-change-my-username-so-that-it-matches-my-github-username/70173)

<div class="topic-metadata">

**Author:** [@giancarloantonucci](https://discourse.julialang.org/u/giancarloantonucci)\
**Replies:** 6\
**Last updated:** [February 3, 2022, 5:00pm UTC](https://discourse.julialang.org/t/can-i-change-my-username-so-that-it-matches-my-github-username/70173 "2022-02-03T17:00:02Z")

</div>

As per title: Can I change my username so that it matches my GitHub username?

---

## [How to use Log10 axis scale for Makie heatmaps](https://discourse.julialang.org/t/how-to-use-log10-axis-scale-for-makie-heatmaps/75722)

<div class="topic-metadata">

**Author:** [@fnoessler](https://discourse.julialang.org/u/fnoessler)\
**Replies:** 2\
**Last updated:** [February 3, 2022, 3:07pm UTC](https://discourse.julialang.org/t/how-to-use-log10-axis-scale-for-makie-heatmaps/75722 "2022-02-03T15:07:52Z")

</div>

Hello, I cannot figure out how to properly set a log10 axis scale for heatmaps. I get an error of invalid x-limits even if I set positive axis limits. I know log10 is not defined for negative values (when I dont want a …

---

## [If and symbol, bug or feature?](https://discourse.julialang.org/t/if-and-symbol-bug-or-feature/75729)

<div class="topic-metadata">

**Author:** [@bertschi](https://discourse.julialang.org/u/bertschi)\
**Replies:** 6\
**Last updated:** [February 3, 2022, 3:12pm UTC](https://discourse.julialang.org/t/if-and-symbol-bug-or-feature/75729 "2022-02-03T15:12:41Z")

</div>

Hi, first of all many thanks for Julia … what a great language! As I could not find this issue, I post it here: When using an if statement with a symbol, the parser seems to understand it differently as I would: if t…

---

## [Efficient way to get indices of true elements from BitArray](https://discourse.julialang.org/t/efficient-way-to-get-indices-of-true-elements-from-bitarray/75731)

<div class="topic-metadata">

**Author:** [@rmsmsgood](https://discourse.julialang.org/u/rmsmsgood)\
**Replies:** 5\
**Last updated:** [February 3, 2022, 3:00pm UTC](https://discourse.julialang.org/t/efficient-way-to-get-indices-of-true-elements-from-bitarray/75731 "2022-02-03T15:00:58Z")

</div>

I usually use the following: x = rand(Bool, 10) (1:length(x))\[x\] Result: julia\> x = rand(Bool, 10) 10-element Vector{Bool}: 0 1 0 0 0 1 1 0 0 0 julia\> (1:length(x))\[x\] 3-element Vector{Int64}: 2 6 7 But…

---

## [How to use DiscreteCallbacks with sundials.jl IDA solver? How to implement reinit!?](https://discourse.julialang.org/t/how-to-use-discretecallbacks-with-sundials-jl-ida-solver-how-to-implement-reinit/75674)

<div class="topic-metadata">

**Author:** [@TobiasFranz](https://discourse.julialang.org/u/TobiasFranz)\
**Replies:** 8\
**Last updated:** [February 3, 2022, 2:36pm UTC](https://discourse.julialang.org/t/how-to-use-discretecallbacks-with-sundials-jl-ida-solver-how-to-implement-reinit/75674 "2022-02-03T14:36:00Z")

</div>

I’m solving large DAE-Systems derived from PDEs for electrochemical systems. I’m using the IDA solver because the ODE solvers (DAE formulated as ODE in mass matrix form) are not working (all of them are unstable) for my …

---

## [DiffEqOperators and DifferentialEquations: solving a coupled system of PDEs](https://discourse.julialang.org/t/diffeqoperators-and-differentialequations-solving-a-coupled-system-of-pdes/74722)

<div class="topic-metadata">

**Author:** [@ash](https://discourse.julialang.org/u/ash)\
**Replies:** 14\
**Last updated:** [February 3, 2022, 2:14pm UTC](https://discourse.julialang.org/t/diffeqoperators-and-differentialequations-solving-a-coupled-system-of-pdes/74722 "2022-02-03T14:14:55Z")

</div>

I am trying to solve a system of coupled PDEs shown below: and . I have written some simple code using DifferentialEquations.jl and DiffEqOperators.jl hoping to solve this system: using DifferentialEquations using…

---

## [Exact solution of linear system with Symbolics](https://discourse.julialang.org/t/exact-solution-of-linear-system-with-symbolics/75718)

<div class="topic-metadata">

**Author:** [@sijo](https://discourse.julialang.org/u/sijo)\
**Replies:** 2\
**Last updated:** [February 3, 2022, 1:37pm UTC](https://discourse.julialang.org/t/exact-solution-of-linear-system-with-symbolics/75718 "2022-02-03T13:37:51Z")

</div>

How can I get an exact solution to a linear system using Symbolics.jl? For example: @variables x y Symbolics.solve\_for(\[x + y ~ 2, x - y ~ 1\], \[x, y\]) # Result: 2-element Vector…

---

## [Julia Programmers Ranked by Contributions](https://discourse.julialang.org/t/julia-programmers-ranked-by-contributions/75572)

<div class="topic-metadata">

**Author:** [@rafael.guerra](https://discourse.julialang.org/u/rafael.guerra)\
**Replies:** 12\
**Last updated:** [February 3, 2022, 1:06pm UTC](https://discourse.julialang.org/t/julia-programmers-ranked-by-contributions/75572 "2022-02-03T13:06:41Z")

</div>

I came across this Julia Programmers Ranked by Contributions, but I don’t really know how to interpret it. Are there any other similar Julia rankings that you are aware of?

---

## [Julia + VSCode Import error from ModelingToolkit](https://discourse.julialang.org/t/julia-vscode-import-error-from-modelingtoolkit/75720)

<div class="topic-metadata">

**Author:** [@koustavpal](https://discourse.julialang.org/u/koustavpal)\
**Replies:** 1\
**Last updated:** [February 3, 2022, 11:40am UTC](https://discourse.julialang.org/t/julia-vscode-import-error-from-modelingtoolkit/75720 "2022-02-03T11:40:07Z")

</div>

Hi, I’m trying to get started with ModelingToolKit. I’m using Julia through a jupyter notebook in VSCode. The environment is different from the default environment used by the command line julia executable. Julia itself…

---

## [Phylodynamic simulations in Julia](https://discourse.julialang.org/t/phylodynamic-simulations-in-julia/75719)

<div class="topic-metadata">

**Author:** [@koustavpal](https://discourse.julialang.org/u/koustavpal)\
**Replies:** 1\
**Last updated:** [February 3, 2022, 11:37am UTC](https://discourse.julialang.org/t/phylodynamic-simulations-in-julia/75719 "2022-02-03T11:37:49Z")

</div>

Hi, I am trying to figure out the best way to perform phylodynamic simulations in Julia. I’ve come across the Gillespie.jl, Biosimulation.jl and the ModellingToolKit.jl packages. Great talk for ModelingToolKit.jl by the…

---

## [Inconsistency with \`reduce(vcat, v)\` when the vector has a single element](https://discourse.julialang.org/t/inconsistency-with-reduce-vcat-v-when-the-vector-has-a-single-element/75694)

<div class="topic-metadata">

**Author:** [@Iagoba\_Apellaniz](https://discourse.julialang.org/u/Iagoba_Apellaniz)\
**Replies:** 4\
**Last updated:** [February 3, 2022, 10:21am UTC](https://discourse.julialang.org/t/inconsistency-with-reduce-vcat-v-when-the-vector-has-a-single-element/75694 "2022-02-03T10:21:14Z")

</div>

Hello! I guess that this might have been discussed somewhere. But I couldn’t find it. I’ll put an example to show the problem, which in my opinion needs at least some consideration julia\> vcat(1,2) == reduce(vcat, \[1,2\]…

---

## [\[ANN\] FaultDetectionTools.jl - Fault Detection and Isolation Tools](https://discourse.julialang.org/t/ann-faultdetectiontools-jl-fault-detection-and-isolation-tools/75663)

<div class="topic-metadata">

**Author:** [@andreasvarga](https://discourse.julialang.org/u/andreasvarga)\
**Replies:** 0\
**Last updated:** [February 2, 2022, 2:37pm UTC](https://discourse.julialang.org/t/ann-faultdetectiontools-jl-fault-detection-and-isolation-tools/75663 "2022-02-02T14:37:29Z")

</div>

I am pleased to announce the release v1.0 of the package FaultDetectionTools for the solution of synthesis problems of fault detection and model detection filters using model-based approaches. These filters are the mai…

---

## [Confusing output of status --outdated while trying out a PR branch](https://discourse.julialang.org/t/confusing-output-of-status-outdated-while-trying-out-a-pr-branch/75707)

<div class="topic-metadata">

**Author:** [@jishnub](https://discourse.julialang.org/u/jishnub)\
**Replies:** 2\
**Last updated:** [February 3, 2022, 10:18am UTC](https://discourse.julialang.org/t/confusing-output-of-status-outdated-while-trying-out-a-pr-branch/75707 "2022-02-03T10:18:29Z")

</div>

I’m trying out an unregistered branch of MKL (@v1.8) pkg\> activate --temp Activating new project at \`/tmp/jl\_LRkm83\` (jl\_LRkm83) pkg\> add https://github.com/JuliaLinearAlgebra/MKL.jl#vs/lp64 Updating git-repo \`ht…

---

## [Outperformed by Matlab](https://discourse.julialang.org/t/outperformed-by-matlab/71603)

<div class="topic-metadata">

**Author:** [@Germinator](https://discourse.julialang.org/u/Germinator)\
**Replies:** 54\
**Last updated:** [November 23, 2021, 7:28pm UTC](https://discourse.julialang.org/t/outperformed-by-matlab/71603 "2021-11-23T19:28:46Z")

</div>

Dear Julia users, I am trying to set up the normal equations ( https://en.wikipedia.org/wiki/Linear\_least\_squares ) which means constructing X'X and X'y in (X'X+\\lambda M) w = X'y where M is SPD, and in my case, each…

---

## [Tracing memory occupied by existing variables](https://discourse.julialang.org/t/tracing-memory-occupied-by-existing-variables/75680)

<div class="topic-metadata">

**Author:** [@Tomas\_Pevny](https://discourse.julialang.org/u/Tomas_Pevny)\
**Replies:** 8\
**Last updated:** [February 3, 2022, 9:02am UTC](https://discourse.julialang.org/t/tracing-memory-occupied-by-existing-variables/75680 "2022-02-03T09:02:03Z")

</div>

Hi All, We are searching for a cause, why our server eventually consumes all memory and crashes, a topic discussed here Poor performance of garbage collection in multi-threaded application We have tried to execute GC m…

[Previous page](https://discourse.julialang.org/latest.md?page=1131)

[Next page](https://discourse.julialang.org/latest.md?page=1133)