# Latest

**URL:** https://discourse.julialang.org/latest.md?page=976

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

**Page:** 977

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## [Benchmarking all() vs for-loop](https://discourse.julialang.org/t/benchmarking-all-vs-for-loop/84483)

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**Author:** [@RobertGregg](https://discourse.julialang.org/u/RobertGregg)\
**Replies:** 4\
**Last updated:** [July 20, 2022, 1:02am UTC](https://discourse.julialang.org/t/benchmarking-all-vs-for-loop/84483 "2022-07-20T01:02:00Z")

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Is it possible to get the same performance from the all() function compared to the for-loop equivalent? v = rand(1:2,1\_000\_000) idx = findall(isequal(1),v) function f1(v,idx) @inbounds for i in idx if v\[i\] …

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## [Parse types from string](https://discourse.julialang.org/t/parse-types-from-string/84518)

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**Author:** [@ohmsweetohm1](https://discourse.julialang.org/u/ohmsweetohm1)\
**Replies:** 2\
**Last updated:** [July 20, 2022, 11:12am UTC](https://discourse.julialang.org/t/parse-types-from-string/84518 "2022-07-20T11:12:03Z")

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If I have a string of a function how can I parse the types from it? str = """ foo( bar::Bar, baz::AbstractVector{Baz}, var::Dict{Symbol,Var}=d, zar::Dict{Symbol,Zar} = k, rar::Dict{Symbol,Rar}, rar::Dict{S…

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## [About StatsKit and Reexport](https://discourse.julialang.org/t/about-statskit-and-reexport/84519)

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**Author:** [@Freya\_the\_Goddess](https://discourse.julialang.org/u/Freya_the_Goddess)\
**Replies:** 1\
**Last updated:** [July 20, 2022, 10:00am UTC](https://discourse.julialang.org/t/about-statskit-and-reexport/84519 "2022-07-20T10:00:37Z")

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I just want to know the example of using StatsKit for DataFrames… why would someone install StatsKit if they already have the packages like Distributions.jl or DataFrames.jl ? Why we need StatsKit with Reexport. A new…

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## [To all noobs like me please read Bogumił Kamiński's blog especially the latest about why he uses main()](https://discourse.julialang.org/t/to-all-noobs-like-me-please-read-bogumil-kaminskis-blog-especially-the-latest-about-why-he-uses-main/84485)

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**Author:** [@anon69491625](https://discourse.julialang.org/u/anon69491625)\
**Replies:** 3\
**Last updated:** [July 20, 2022, 9:57am UTC](https://discourse.julialang.org/t/to-all-noobs-like-me-please-read-bogumil-kaminskis-blog-especially-the-latest-about-why-he-uses-main/84485 "2022-07-20T09:57:16Z")

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Hi all I would suggest that a LOT my MANY mistakes in julia would have been avoided by reading Bogumił Kamiński’s blog entries. They are FUN, easy to read and informative. This latest one knocks it out of the ball park…

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## [Creating a function that does not import outer scope variables](https://discourse.julialang.org/t/creating-a-function-that-does-not-import-outer-scope-variables/84481)

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**Author:** [@raphaelchinchilla](https://discourse.julialang.org/u/raphaelchinchilla)\
**Replies:** 7\
**Last updated:** [July 20, 2022, 9:52am UTC](https://discourse.julialang.org/t/creating-a-function-that-does-not-import-outer-scope-variables/84481 "2022-07-20T09:52:26Z")

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Julia allows functions to see variables outside of their scope, something like y=2 function f(x) x+y end I agree this can often be useful, but for me this is generally a source of bugs. A typical error that I do is …

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## [Question about String index?](https://discourse.julialang.org/t/question-about-string-index/84520)

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**Author:** [@Raymond](https://discourse.julialang.org/u/Raymond)\
**Replies:** 3\
**Last updated:** [July 20, 2022, 9:32am UTC](https://discourse.julialang.org/t/question-about-string-index/84520 "2022-07-20T09:32:04Z")

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Dear all, julia\> s = "abcdefg" "abcdefg" julia\> s\[end-4, end\] ERROR: MethodError: no method matching axes(::String, ::Int64) Closest candidates are: axes(::AbstractDataFrame, ::Integer) at ~/.julia/packages/DataFrame…

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## [Inplace array modification performances](https://discourse.julialang.org/t/inplace-array-modification-performances/84044)

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**Author:** [@dgasteau](https://discourse.julialang.org/u/dgasteau)\
**Replies:** 4\
**Last updated:** [July 20, 2022, 7:09am UTC](https://discourse.julialang.org/t/inplace-array-modification-performances/84044 "2022-07-20T07:09:48Z")

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Hi, I am trying to improve the memory management of some complex iterative procedure. Basically the procedure could be synthesized to for ii = 1:Nt do some partial arrays value update Compute some stuff (include fft…

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## [Unpacking from a collection](https://discourse.julialang.org/t/unpacking-from-a-collection/84276)

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**Author:** [@uje](https://discourse.julialang.org/u/uje)\
**Replies:** 5\
**Last updated:** [July 20, 2022, 6:27am UTC](https://discourse.julialang.org/t/unpacking-from-a-collection/84276 "2022-07-20T06:27:56Z")

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In python I could do this and the result will be as follows \>\>\> a, b, \*c, d = \[1, 2, 3, 4, 5, 6\] \>\>\>a 1 \>\>\>b 2 \>\>\>c \[3, 4, 5\] \>\>\>d 6 I know there’s unpacking in Julia and know how to use it. But the part where I can pa…

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## [Julia v1.6.7 has been released](https://discourse.julialang.org/t/julia-v1-6-7-has-been-released/84504)

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**Author:** [@ararslan](https://discourse.julialang.org/u/ararslan)\
**Replies:** 0\
**Last updated:** [July 20, 2022, 5:28am UTC](https://discourse.julialang.org/t/julia-v1-6-7-has-been-released/84504 "2022-07-20T05:28:21Z")

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Julia version 1.6.7, the seventh patch release in the 1.6 LTS series of releases, is now available. Binaries are available at https://julialang.org/downloads in the “long-term support (LTS) release” section for the follo…

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## [LinearMap : error while running LinearMap](https://discourse.julialang.org/t/linearmap-error-while-running-linearmap/41966)

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**Author:** [@saikrishna](https://discourse.julialang.org/u/saikrishna)\
**Replies:** 17\
**Last updated:** [July 20, 2022, 4:12am UTC](https://discourse.julialang.org/t/linearmap-error-while-running-linearmap/41966 "2022-07-20T04:12:15Z")

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I tried to run Julia-1.6.0 dev version in my laptop. When running the LinearMap function, I encountered an error, which I have attached along with this query. I would like any suggestions to improve. Thanks in advance, …

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## [Vector{Task}() and Vector{Task}](https://discourse.julialang.org/t/vector-task-and-vector-task/84500)

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**Author:** [@marllos](https://discourse.julialang.org/u/marllos)\
**Replies:** 4\
**Last updated:** [July 20, 2022, 3:54am UTC](https://discourse.julialang.org/t/vector-task-and-vector-task/84500 "2022-07-20T03:54:28Z")

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Hello everyone! What is the difference between Vector{Task}() and Vector{Task}? The code below does not work with Vector{Task}, only with Vector{Task}(). Is there a better way to write this code? Julia Version 1.7.3 f…

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## [Clarification about the "be concise" section in the community standards guideline](https://discourse.julialang.org/t/clarification-about-the-be-concise-section-in-the-community-standards-guideline/84453)

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**Author:** [@rht](https://discourse.julialang.org/u/rht)\
**Replies:** 7\
**Last updated:** [July 20, 2022, 2:55am UTC](https://discourse.julialang.org/t/clarification-about-the-be-concise-section-in-the-community-standards-guideline/84453 "2022-07-20T02:55:31Z")

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Quoting the content of the relevant section in the community standards guideline Constructive criticism and suggestions are welcome, but high-traffic forums do not generally have the bandwidth for extensive discourse. …

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## [Constraint seems linear but the compiler determined it was quadratic. Not sure why or how to fix](https://discourse.julialang.org/t/constraint-seems-linear-but-the-compiler-determined-it-was-quadratic-not-sure-why-or-how-to-fix/84426)

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**Author:** [@johnabs](https://discourse.julialang.org/u/johnabs)\
**Replies:** 10\
**Last updated:** [July 20, 2022, 1:52am UTC](https://discourse.julialang.org/t/constraint-seems-linear-but-the-compiler-determined-it-was-quadratic-not-sure-why-or-how-to-fix/84426 "2022-07-20T01:52:39Z")

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Hi all, I’m doing some optimization on weighted graphs, and one of my constraints is showing up as quadratic for some reason, and JuMP says it’s can’t convert it to Affine, even though the docs say this is possible. (“B…

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## [Need help for github action adaption](https://discourse.julialang.org/t/need-help-for-github-action-adaption/84439)

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**Author:** [@Rratic](https://discourse.julialang.org/u/Rratic)\
**Replies:** 1\
**Last updated:** [July 19, 2022, 11:50pm UTC](https://discourse.julialang.org/t/need-help-for-github-action-adaption/84439 "2022-07-19T23:50:15Z")

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Currently I’m developing a package and wants it to be easily used by github actions, and I plan to write the code under src/git.jl But the problem is I can’t figure out what I should do after reading related docs and vi…

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## [\[ANN\] Virtual.jl: optimizing dynamic calls away through "virtual" multiple dispatch](https://discourse.julialang.org/t/ann-virtual-jl-optimizing-dynamic-calls-away-through-virtual-multiple-dispatch/84413)

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**Author:** [@thautwarm](https://discourse.julialang.org/u/thautwarm)\
**Replies:** 14\
**Last updated:** [July 19, 2022, 10:43pm UTC](https://discourse.julialang.org/t/ann-virtual-jl-optimizing-dynamic-calls-away-through-virtual-multiple-dispatch/84413 "2022-07-19T22:43:56Z")

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P.S: Recently I’m planning to implement a zero-latency scripting language in Julia, hence I need this feature. The package can be regarded as a generalization to ValSplit.jl, supporting fast runtime polymorphisms for mul…

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## [Passing jacobian generated from ModelingToolkit to ODEFunction for EnsembleGPUArray](https://discourse.julialang.org/t/passing-jacobian-generated-from-modelingtoolkit-to-odefunction-for-ensemblegpuarray/84198)

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**Author:** [@RicardoFR](https://discourse.julialang.org/u/RicardoFR)\
**Replies:** 7\
**Last updated:** [July 19, 2022, 10:52pm UTC](https://discourse.julialang.org/t/passing-jacobian-generated-from-modelingtoolkit-to-odefunction-for-ensemblegpuarray/84198 "2022-07-19T22:52:43Z")

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Hello all! I want to do some tests with GPU Parallel Ensemble Simulation using DifferentialEquations.jl. As a starting point, I was looking into the example in the DiffEqGPU.jl page. Regarding Stiff ODEs, it’s said that…

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## [Drawing an ellipsoid to visualize a tensor](https://discourse.julialang.org/t/drawing-an-ellipsoid-to-visualize-a-tensor/31286)

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**Author:** [@KirillGerke](https://discourse.julialang.org/u/KirillGerke)\
**Replies:** 10\
**Last updated:** [July 19, 2022, 10:33pm UTC](https://discourse.julialang.org/t/drawing-an-ellipsoid-to-visualize-a-tensor/31286 "2022-07-19T22:33:54Z")

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Dear All, I am struggling with some problem in writing my code in Julia and, thus, ask for your assistance… What i want to do: visualize a tensor (3x3 matrix) as ellipsoid Problem: 1) not sure about which graphical fr…

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## [Is there anything users can do to help move Apple Silicon support from Tier 3 to Tier 1?](https://discourse.julialang.org/t/is-there-anything-users-can-do-to-help-move-apple-silicon-support-from-tier-3-to-tier-1/72739)

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**Author:** [@CameronBieganek](https://discourse.julialang.org/u/CameronBieganek)\
**Replies:** 33\
**Last updated:** [July 19, 2022, 10:17pm UTC](https://discourse.julialang.org/t/is-there-anything-users-can-do-to-help-move-apple-silicon-support-from-tier-3-to-tier-1/72739 "2022-07-19T22:17:34Z")

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Is there anything users can do to help move Apple Silicon support from Tier 3 to Tier 1? Given that most new Mac machines now have an M1 chip, it seems like there will be more and more Julia programmers wanting to use a …

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## [Generating group id column in DataFrames?](https://discourse.julialang.org/t/generating-group-id-column-in-dataframes/83768)

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**Author:** [@Raymond](https://discourse.julialang.org/u/Raymond)\
**Replies:** 17\
**Last updated:** [July 19, 2022, 9:42pm UTC](https://discourse.julialang.org/t/generating-group-id-column-in-dataframes/83768 "2022-07-19T21:42:57Z")

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Here is an example data. julia\> b = DataFrame(city = \["BJ", "BJ", "BJ", "HF", "HF", "TS", "TS"\], year = \[1990, 1991, 1992, 1990, 1991, 1990, 1991\], cpi = \[1, 2, 3, 4, 5, 2, 1\]) 7×3 DataFrame Row │ city year cpi …

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## [Why does Julia 1.6.5 and 1.7.1 generate differnent random values using the same seed?](https://discourse.julialang.org/t/why-does-julia-1-6-5-and-1-7-1-generate-differnent-random-values-using-the-same-seed/84482)

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**Author:** [@etorkia](https://discourse.julialang.org/u/etorkia)\
**Replies:** 4\
**Last updated:** [July 19, 2022, 9:02pm UTC](https://discourse.julialang.org/t/why-does-julia-1-6-5-and-1-7-1-generate-differnent-random-values-using-the-same-seed/84482 "2022-07-19T21:02:11Z")

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I found that if you start a fresh session in both 1.6.5. and 1.7.1 you get different results. I found this glitch while running doctests… and I will never be able to run Documenter.jl with this kind of craziness. using …

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## [Count number of overlapping polygons with Julia?](https://discourse.julialang.org/t/count-number-of-overlapping-polygons-with-julia/57400)

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**Author:** [@vlandau](https://discourse.julialang.org/u/vlandau)\
**Replies:** 2\
**Last updated:** [July 19, 2022, 8:36pm UTC](https://discourse.julialang.org/t/count-number-of-overlapping-polygons-with-julia/57400 "2022-07-19T20:36:30Z")

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Hi all, I have a series of partially overlapping polygons in a single shapefile, and I need to create a new shapefile that has the number of overlapping polygons in each intersection. e.g. this. There is a way to do it …

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## [Convert Non-linear objective function from Maximization to Minimization](https://discourse.julialang.org/t/convert-non-linear-objective-function-from-maximization-to-minimization/84478)

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**Author:** [@sophiepavia](https://discourse.julialang.org/u/sophiepavia)\
**Replies:** 3\
**Last updated:** [July 19, 2022, 8:31pm UTC](https://discourse.julialang.org/t/convert-non-linear-objective-function-from-maximization-to-minimization/84478 "2022-07-19T20:31:26Z")

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Hello! I have the following non linear objective function. How can I convert this maximization objective function to a minimization problem? I have read conflicting material online, some say to multiple the problem by …

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## [Complex colormap in Julia Plots?](https://discourse.julialang.org/t/complex-colormap-in-julia-plots/84212)

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**Author:** [@PrintRind](https://discourse.julialang.org/u/PrintRind)\
**Replies:** 8\
**Last updated:** [July 19, 2022, 8:19pm UTC](https://discourse.julialang.org/t/complex-colormap-in-julia-plots/84212 "2022-07-19T20:19:32Z")

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Hi, is there any colormap that can be used together with Julia Plots that encodes amplitude and phase of a complex field in a single color plot? E.g. hue encodes the phase and “lightness” or value the amplitude. Simil…

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## [2022 Julia User & Developer Survey and Julia T-Shirt Contest](https://discourse.julialang.org/t/2022-julia-user-developer-survey-and-julia-t-shirt-contest/83910)

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**Author:** [@ahclaster](https://discourse.julialang.org/u/ahclaster)\
**Replies:** 3\
**Last updated:** [July 19, 2022, 7:45pm UTC](https://discourse.julialang.org/t/2022-julia-user-developer-survey-and-julia-t-shirt-contest/83910 "2022-07-19T19:45:28Z")

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The 2022 Julia User & Developer Survey is open now - please respond today! The survey is available in English, Japanese and Spanish. Results will be presented at JuliaCon (past results). Respondents are invited to enter …

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## [Sentry support for Julia](https://discourse.julialang.org/t/sentry-support-for-julia/21237)

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**Author:** [@mrkaspa](https://discourse.julialang.org/u/mrkaspa)\
**Replies:** 6\
**Last updated:** [July 19, 2022, 7:34pm UTC](https://discourse.julialang.org/t/sentry-support-for-julia/21237 "2022-07-19T19:34:27Z")

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Has anyone have used sentry Platforms | Sentry Documentation with julia I can not find a package for it

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## [Speeding up some non-optimized Julia functions](https://discourse.julialang.org/t/speeding-up-some-non-optimized-julia-functions/84358)

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**Author:** [@O\_Julia](https://discourse.julialang.org/u/O_Julia)\
**Replies:** 47\
**Last updated:** [July 19, 2022, 7:09pm UTC](https://discourse.julialang.org/t/speeding-up-some-non-optimized-julia-functions/84358 "2022-07-19T19:09:07Z")

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Hi, I am converting some of my Python codes to Julia language. For minimal working example, I have simplified most time consuming part of my codes and give them below. In the current version. The Python codes are approxi…

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## [Why does Random.seed!() return different results in Atom and VSCode?](https://discourse.julialang.org/t/why-does-random-seed-return-different-results-in-atom-and-vscode/84287)

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**Author:** [@etorkia](https://discourse.julialang.org/u/etorkia)\
**Replies:** 3\
**Last updated:** [July 19, 2022, 6:18pm UTC](https://discourse.julialang.org/t/why-does-random-seed-return-different-results-in-atom-and-vscode/84287 "2022-07-19T18:18:48Z")

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I am trying to run Documenter.jl and the output results are different that the expected results due to a difference in sampling. I can reproduce a seeded result using 1 in both cases but different outputs! Any thoughts?

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## [Is there any reason to use NaN instead of missing?](https://discourse.julialang.org/t/is-there-any-reason-to-use-nan-instead-of-missing/84396)

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**Author:** [@Benny](https://discourse.julialang.org/u/Benny)\
**Replies:** 11\
**Last updated:** [July 19, 2022, 5:59pm UTC](https://discourse.julialang.org/t/is-there-any-reason-to-use-nan-instead-of-missing/84396 "2022-07-19T17:59:27Z")

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I know that NaN isn’t going away because of the IEEE 754 standard on floating point behavior, but is there ever a reason to use NaN instead of converting and using missings as much as possible? Both are propagating non-v…

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## [Change construction type parameters for a type in a vector?](https://discourse.julialang.org/t/change-construction-type-parameters-for-a-type-in-a-vector/84441)

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**Author:** [@emmettgb](https://discourse.julialang.org/u/emmettgb)\
**Replies:** 14\
**Last updated:** [July 19, 2022, 5:52pm UTC](https://discourse.julialang.org/t/change-construction-type-parameters-for-a-type-in-a-vector/84441 "2022-07-19T17:52:17Z")

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I have an abstract type: abstract type Pickle end I have a sub-type mutable struct Dill \<: Pickle rating::Integer end If I construct a Vector{Dill}: \[Dill(5), Dill(6,)\] The type of this is Vector{Dill}. What I …

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## [Research Engineer position at CNRM-CEN, Grenoble, France](https://discourse.julialang.org/t/research-engineer-position-at-cnrm-cen-grenoble-france/84480)

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**Author:** [@simonbyrne](https://discourse.julialang.org/u/simonbyrne)\
**Replies:** 0\
**Last updated:** [July 19, 2022, 5:03pm UTC](https://discourse.julialang.org/t/research-engineer-position-at-cnrm-cen-grenoble-france/84480 "2022-07-19T17:03:02Z")

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Design and implementation of a new physical snow model in Julia. For more details, see

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