# Latest

**URL:** https://discourse.julialang.org/latest.md?page=925

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

**Page:** 926

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## [Manipulating Panel Data in Julia](https://discourse.julialang.org/t/manipulating-panel-data-in-julia/83109)

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**Author:** [@IljaK91](https://discourse.julialang.org/u/IljaK91)\
**Replies:** 6\
**Last updated:** [September 13, 2022, 6:30pm UTC](https://discourse.julialang.org/t/manipulating-panel-data-in-julia/83109 "2022-09-13T18:30:23Z")

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Hey everyone, I was looking for a straightforward way to do common manipulations in panel data within Julia. For instance, let’s say I have a panel of many countries and years. I would like to calculate the growth rate …

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## [Why does the first enum member value default to zero instead of one?](https://discourse.julialang.org/t/why-does-the-first-enum-member-value-default-to-zero-instead-of-one/87219)

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**Author:** [@mthelm85](https://discourse.julialang.org/u/mthelm85)\
**Replies:** 3\
**Last updated:** [September 13, 2022, 6:13pm UTC](https://discourse.julialang.org/t/why-does-the-first-enum-member-value-default-to-zero-instead-of-one/87219 "2022-09-13T18:13:57Z")

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I’m just curious since Julia uses 1-based indexing. E.g. julia\> @enum Color Red Blue julia\> Red Red::Color = 0 julia\> Blue Blue::Color = 1

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## [TrajectoryOptimization.jl minimal time problem](https://discourse.julialang.org/t/trajectoryoptimization-jl-minimal-time-problem/82795)

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**Author:** [@a6a3uh](https://discourse.julialang.org/u/a6a3uh)\
**Replies:** 17\
**Last updated:** [September 13, 2022, 6:13pm UTC](https://discourse.julialang.org/t/trajectoryoptimization-jl-minimal-time-problem/82795 "2022-09-13T18:13:12Z")

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Maybe some of authors of the package are around here to answer the question. Is it possible to formulate minimal time trajectory optimization problem with TrajectoryOptimization.jl? How can I go about if I don’t know in …

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## [Automatic bifurcation diagram for a simple model](https://discourse.julialang.org/t/automatic-bifurcation-diagram-for-a-simple-model/87227)

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**Author:** [@zmoitier](https://discourse.julialang.org/u/zmoitier)\
**Replies:** 0\
**Last updated:** [September 13, 2022, 5:43pm UTC](https://discourse.julialang.org/t/automatic-bifurcation-diagram-for-a-simple-model/87227 "2022-09-13T17:43:11Z")

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I am trying to compute the bifurcation diagram using BifucationKit.jl associated to the equation: find a vector u and a scalar λ such that Au - λu - u.^3 = 0 where A is a real symmetric matrix. For this problem, the theo…

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## [Save and restore namespace](https://discourse.julialang.org/t/save-and-restore-namespace/87120)

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**Author:** [@Rossati](https://discourse.julialang.org/u/Rossati)\
**Replies:** 7\
**Last updated:** [September 13, 2022, 4:06pm UTC](https://discourse.julialang.org/t/save-and-restore-namespace/87120 "2022-09-13T16:06:52Z")

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Hi I am trying to generate a form using gtk in module; the problem arise when I (de)generate two form because the data of the second form obfuscates that of the first. I only have two alternatives in mind: save the n…

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## [Understanding on MetaProgramming](https://discourse.julialang.org/t/understanding-on-metaprogramming/87223)

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**Author:** [@Brian1](https://discourse.julialang.org/u/Brian1)\
**Replies:** 0\
**Last updated:** [September 13, 2022, 3:59pm UTC](https://discourse.julialang.org/t/understanding-on-metaprogramming/87223 "2022-09-13T15:59:11Z")

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I has had always been much difficulty on understaning MetaProgramming. Here is an example. I tried again and again to get to the target. These codes works fine. But I believe thers must be some more brief way to get to …

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## [Migrating old html posts to Franklin](https://discourse.julialang.org/t/migrating-old-html-posts-to-franklin/87214)

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**Author:** [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Replies:** 1\
**Last updated:** [September 13, 2022, 3:52pm UTC](https://discourse.julialang.org/t/migrating-old-html-posts-to-franklin/87214 "2022-09-13T15:52:36Z")

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I would like to migrate my old Hugo-based setup to Franklin. I am not going to re-edit the Markdown files, so I just want to copy over everything (generated HTML) in post/ so that the old links indexed in search engines…

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## [VSCode julia terminal goes partially white-on-white after screensaver wake (linux)](https://discourse.julialang.org/t/vscode-julia-terminal-goes-partially-white-on-white-after-screensaver-wake-linux/87222)

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**Author:** [@dlakelan](https://discourse.julialang.org/u/dlakelan)\
**Replies:** 0\
**Last updated:** [September 13, 2022, 3:39pm UTC](https://discourse.julialang.org/t/vscode-julia-terminal-goes-partially-white-on-white-after-screensaver-wake-linux/87222 "2022-09-13T15:39:04Z")

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Anyone else seen this behavior? I typed “foobar” at the prompt, but only the b shows up, none of the warnings are visible… etc. On Linux, with nvidia drivers. Changing the color theme, and then changing it back fix…

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## [Why doesn't \`vect\` return a union-typed result if the number of elements is small?](https://discourse.julialang.org/t/why-doesnt-vect-return-a-union-typed-result-if-the-number-of-elements-is-small/87155)

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**Author:** [@jishnub](https://discourse.julialang.org/u/jishnub)\
**Replies:** 3\
**Last updated:** [September 13, 2022, 3:28pm UTC](https://discourse.julialang.org/t/why-doesnt-vect-return-a-union-typed-result-if-the-number-of-elements-is-small/87155 "2022-09-13T15:28:41Z")

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Eg.: julia\> struct A end julia\> struct B end julia\> \[A(), B()\] 2-element Vector{Any}: A() B() Would it not be better to return julia\> Union{A,B}\[A(), B()\] 2-element Vector{Union{A, B}}: A() B() instead, as this…

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## [Juliaup on linux & systemd](https://discourse.julialang.org/t/juliaup-on-linux-systemd/87196)

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**Author:** [@Steven\_Sagaert](https://discourse.julialang.org/u/Steven_Sagaert)\
**Replies:** 2\
**Last updated:** [September 13, 2022, 3:13pm UTC](https://discourse.julialang.org/t/juliaup-on-linux-systemd/87196 "2022-09-13T15:13:42Z")

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Hi, I’ve installed juliaup on a CentOS 8.3 server and everything works fine for interactive use. However when I try to start a service via systemd it fails. Note that I have installed juliaup (& julia) as root user and…

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## [How to return one value for a Matrix comparison with a value?](https://discourse.julialang.org/t/how-to-return-one-value-for-a-matrix-comparison-with-a-value/87159)

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**Author:** [@Amro](https://discourse.julialang.org/u/Amro)\
**Replies:** 7\
**Last updated:** [September 13, 2022, 2:24pm UTC](https://discourse.julialang.org/t/how-to-return-one-value-for-a-matrix-comparison-with-a-value/87159 "2022-09-13T14:24:28Z")

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I want to compare the values of a matrix with a value (such such if bigger than zero) and return true if so. How can I do that, cause below is returning a mtrix? julia\> RR=ones(5,10) 5×10 Matrix{Float64}: 1.0 1.0 1.0…

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## [Julia 1.8.1 absolutely does not work in VSCode](https://discourse.julialang.org/t/julia-1-8-1-absolutely-does-not-work-in-vscode/87141)

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**Author:** [@abharg](https://discourse.julialang.org/u/abharg)\
**Replies:** 11\
**Last updated:** [September 13, 2022, 2:15pm UTC](https://discourse.julialang.org/t/julia-1-8-1-absolutely-does-not-work-in-vscode/87141 "2022-09-13T14:15:17Z")

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I have tried uninstalling and reinstalling Julia 1.8.1, I have tried uninstalling and reinstalling VSCode, I have tried uninstalling and reinstalling the Julia extension in VSCode, I have checked that the settings.json f…

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## [Relocation target is out of range using JITLink](https://discourse.julialang.org/t/relocation-target-is-out-of-range-using-jitlink/79568)

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**Author:** [@alexfanqi](https://discourse.julialang.org/u/alexfanqi)\
**Replies:** 8\
**Last updated:** [September 13, 2022, 1:49pm UTC](https://discourse.julialang.org/t/relocation-target-is-out-of-range-using-jitlink/79568 "2022-09-13T13:49:35Z")

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Hi there, I am testing my luck to port julia to riscv64. I know this is not a supported platform, but I can almost get a sysimage with a bit dirty hacks, except that I get stuck in bootstrapping SuiteSparse/src/cholmod.…

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## [Updating to the current stable release (v1.8.1) using juliaup](https://discourse.julialang.org/t/updating-to-the-current-stable-release-v1-8-1-using-juliaup/87132)

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**Author:** [@rud-lucien](https://discourse.julialang.org/u/rud-lucien)\
**Replies:** 4\
**Last updated:** [September 13, 2022, 2:11pm UTC](https://discourse.julialang.org/t/updating-to-the-current-stable-release-v1-8-1-using-juliaup/87132 "2022-09-13T14:11:30Z")

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Hi, I was attempting to update to the latest stable release of Julia (v1.8.1) using juliaup, however I was unsuccessful. I tried \[juliaup self update\] and \[juliaup update release\] commands but was only able to update to…

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## [Using fixed points from dynamicalsystems.jl in BifurcationKit.jl](https://discourse.julialang.org/t/using-fixed-points-from-dynamicalsystems-jl-in-bifurcationkit-jl/87213)

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**Author:** [@Sergey\_Novak](https://discourse.julialang.org/u/Sergey_Novak)\
**Replies:** 4\
**Last updated:** [September 13, 2022, 2:08pm UTC](https://discourse.julialang.org/t/using-fixed-points-from-dynamicalsystems-jl-in-bifurcationkit-jl/87213 "2022-09-13T14:08:19Z")

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I find fixed points by changing two parameters of a continuous system using the fixed point() function. How correctly use finded fixed points for plotting bifurcation diagram by BifurcationKit.jl? Are there any examp…

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## [Robust date conversion from string to DateTime](https://discourse.julialang.org/t/robust-date-conversion-from-string-to-datetime/87215)

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**Author:** [@scotts](https://discourse.julialang.org/u/scotts)\
**Replies:** 1\
**Last updated:** [September 13, 2022, 2:01pm UTC](https://discourse.julialang.org/t/robust-date-conversion-from-string-to-datetime/87215 "2022-09-13T14:01:47Z")

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I am having to convert dates in the following string format “24/9/2020” to DateTime format. DateTime does not deal with this basic format. I have come up with the following solution that does this for the data I’m deal…

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## [Finding possible keyword arguments](https://discourse.julialang.org/t/finding-possible-keyword-arguments/40752)

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**Author:** [@fgerick](https://discourse.julialang.org/u/fgerick)\
**Replies:** 18\
**Last updated:** [September 13, 2022, 1:23pm UTC](https://discourse.julialang.org/t/finding-possible-keyword-arguments/40752 "2022-09-13T13:23:39Z")

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This is inspired by this post: Is there a way of finding allowed keyword arguments for a function (e.g. bar) that passes its kwargs to another function, such as foo(;a=2,b=3) = a+b bar(;kwargs...) = foo(; kwargs...) s…

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## [Withprogress for Folds.jl](https://discourse.julialang.org/t/withprogress-for-folds-jl/87212)

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**Author:** [@joeldahne](https://discourse.julialang.org/u/joeldahne)\
**Replies:** 0\
**Last updated:** [September 13, 2022, 1:16pm UTC](https://discourse.julialang.org/t/withprogress-for-folds-jl/87212 "2022-09-13T13:16:46Z")

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I have been using Folds.jl for some computations and wanted to add a progress bar. I founds a withprogress function in Transducers.jl but it doesn’t seem to work with Folds.jl, at least not directly. This works using Fo…

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## [When is metaprogramming the best solution?](https://discourse.julialang.org/t/when-is-metaprogramming-the-best-solution/87197)

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**Author:** [@AwesomeQuest](https://discourse.julialang.org/u/AwesomeQuest)\
**Replies:** 2\
**Last updated:** [September 13, 2022, 1:08pm UTC](https://discourse.julialang.org/t/when-is-metaprogramming-the-best-solution/87197 "2022-09-13T13:08:28Z")

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Julia has all these fancy metaprogramming features but when is it actually most optimal or comfortable to use them? Follow up question: Is it ever worth it use metaprogramming in a complicated way?

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## [Video Frame Stacking for Nightsky videos](https://discourse.julialang.org/t/video-frame-stacking-for-nightsky-videos/87211)

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**Author:** [@Allan\_Baker](https://discourse.julialang.org/u/Allan_Baker)\
**Replies:** 0\
**Last updated:** [September 13, 2022, 12:15pm UTC](https://discourse.julialang.org/t/video-frame-stacking-for-nightsky-videos/87211 "2022-09-13T12:15:12Z")

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Anyone using Julia to do frame stacking to enhance night images of the sky from Webcams or Iphones, etc.

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## [Does Julia have more regressions than other languages? Possible solutions](https://discourse.julialang.org/t/does-julia-have-more-regressions-than-other-languages-possible-solutions/87203)

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**Author:** [@Palli](https://discourse.julialang.org/u/Palli)\
**Replies:** 1\
**Last updated:** [September 13, 2022, 12:05pm UTC](https://discourse.julialang.org/t/does-julia-have-more-regressions-than-other-languages-possible-solutions/87203 "2022-09-13T12:05:23Z")

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First, I’m just asking what other people feel or know regarding compared to other languages, say Python or C++. This one, and BigInt in general isn’t a huge concern, just a talking point: Another: I DO see regressio…

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## [Mapslices very slow](https://discourse.julialang.org/t/mapslices-very-slow/86826)

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**Author:** [@Lincoln\_Hannah](https://discourse.julialang.org/u/Lincoln_Hannah)\
**Replies:** 3\
**Last updated:** [September 13, 2022, 11:56am UTC](https://discourse.julialang.org/t/mapslices-very-slow/86826 "2022-09-13T11:56:53Z")

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new to CUDA mapsilces seems to run very slow. reduce is very fast but requires an accumulator (e.g. +) instead of a function (e.g. sum). I’d like to apply the linear\_interpolation function to slices of a matrix (or t…

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## [Able to use Plots without adding it to the active environment](https://discourse.julialang.org/t/able-to-use-plots-without-adding-it-to-the-active-environment/87201)

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**Author:** [@tom-plaa](https://discourse.julialang.org/u/tom-plaa)\
**Replies:** 4\
**Last updated:** [September 13, 2022, 11:33am UTC](https://discourse.julialang.org/t/able-to-use-plots-without-adding-it-to-the-active-environment/87201 "2022-09-13T11:33:14Z")

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As the title implies, I am able to use Plots without adding it to the active environment. It does not disrupt my workflow; in fact, it’s very convenient for testing my modules. I just created the thread because I would …

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## [Overload function application](https://discourse.julialang.org/t/overload-function-application/87205)

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**Author:** [@qwerty](https://discourse.julialang.org/u/qwerty)\
**Replies:** 1\
**Last updated:** [September 13, 2022, 11:24am UTC](https://discourse.julialang.org/t/overload-function-application/87205 "2022-09-13T11:24:25Z")

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I defined a struct like this: struct MyType a::Float64 end The problem is that I want to use all the functions defined on Float64 on MyType without having to rewrite them all. What is the best way to do this? My a…

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## [Debugging Julia code in VSCode opens Python debugger instead](https://discourse.julialang.org/t/debugging-julia-code-in-vscode-opens-python-debugger-instead/87198)

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**Author:** [@Shayan](https://discourse.julialang.org/u/Shayan)\
**Replies:** 1\
**Last updated:** [September 13, 2022, 10:27am UTC](https://discourse.julialang.org/t/debugging-julia-code-in-vscode-opens-python-debugger-instead/87198 "2022-09-13T10:27:40Z")

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I’m trying to debug a Julia script in VSCode, But the debugger opens the Python debugger instead: There isn’t an option for debugging .jl files. According to the official doc, I can hit F5 to trigger the debugger…

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## [How to Clean Julia Directory, Registries, etc After Long Usage?](https://discourse.julialang.org/t/how-to-clean-julia-directory-registries-etc-after-long-usage/87194)

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**Author:** [@Freya\_the\_Goddess](https://discourse.julialang.org/u/Freya_the_Goddess)\
**Replies:** 2\
**Last updated:** [September 13, 2022, 10:17am UTC](https://discourse.julialang.org/t/how-to-clean-julia-directory-registries-etc-after-long-usage/87194 "2022-09-13T10:17:03Z")

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Hi all, I have been using Julia everyday, I understand why people love Julia lang… #MeToo Thus, today I want to clean up things, where / which directories to clean? I am using Linux OS. Must be a lot of stacks that can …

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## [Findn(triu()) in Julia](https://discourse.julialang.org/t/findn-triu-in-julia/87167)

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**Author:** [@m\_shah2](https://discourse.julialang.org/u/m_shah2)\
**Replies:** 7\
**Last updated:** [September 13, 2022, 6:47am UTC](https://discourse.julialang.org/t/findn-triu-in-julia/87167 "2022-09-13T06:47:36Z")

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I am trying to run ai, aj = findn(triu(NA, 1)) and I am getting an error of function not defined UndefVarError: triu not defined Stacktrace: \[1\] top-level scope @ In\[62\]:2 \[2\] eval @ .\\boot.jl:368 \[inlined\] \[3\] in…

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## [ReinforcementLearning Gym spaces](https://discourse.julialang.org/t/reinforcementlearning-gym-spaces/87061)

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**Author:** [@chunky](https://discourse.julialang.org/u/chunky)\
**Replies:** 2\
**Last updated:** [September 13, 2022, 6:46am UTC](https://discourse.julialang.org/t/reinforcementlearning-gym-spaces/87061 "2022-09-13T06:46:51Z")

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I have a C++ Gym exposed as a C .dll/.so whose API was originally designed to be used for a Python OpenAI Gym using ctypes. Specifically, this only relies on “Box” for both action and observation; the continuous, multidi…

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## [The future of Julia, 1.6, 1.7-rc1, 1.8, 1.9, 1.10 and 2.0 and LTS](https://discourse.julialang.org/t/the-future-of-julia-1-6-1-7-rc1-1-8-1-9-1-10-and-2-0-and-lts/68143)

<div class="topic-metadata">

**Author:** [@Palli](https://discourse.julialang.org/u/Palli)\
**Replies:** 16\
**Last updated:** [September 13, 2022, 6:46am UTC](https://discourse.julialang.org/t/the-future-of-julia-1-6-1-7-rc1-1-8-1-9-1-10-and-2-0-and-lts/68143 "2022-09-13T06:46:44Z")

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Julia 1.7-rc1 \[EDIT: is done, 1.7-rc2 is coming\]. Julia 1.6 has been approved as LTS, while not yet announced (I would rather want 1.7 as LTS, but it’s not up to me). Julia 1.0.x has been the long-term support (LTS) rel…

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## [FLoops for updating a vector by index](https://discourse.julialang.org/t/floops-for-updating-a-vector-by-index/87186)

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**Author:** [@DanielVandH](https://discourse.julialang.org/u/DanielVandH)\
**Replies:** 7\
**Last updated:** [September 13, 2022, 6:03am UTC](https://discourse.julialang.org/t/floops-for-updating-a-vector-by-index/87186 "2022-09-13T06:03:40Z")

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I want to make the following function parallel. function build\_vector\_explicit(du, elements) for k ∈ elements du\[k\] += sin(k) end return nothing end This function takes in a vector du (not necessari…

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