# General Usage

**URL:** https://discourse.julialang.org/c/usage/6.md?page=326

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

**Page:** 327

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## [Arpack is broken?](https://discourse.julialang.org/t/arpack-is-broken/94758)

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**Author:** [@marianoarnaiz](https://discourse.julialang.org/u/marianoarnaiz)\
**Replies:** 3\
**Last updated:** [February 19, 2023, 7:29pm UTC](https://discourse.julialang.org/t/arpack-is-broken/94758 "2023-02-19T19:29:35Z")

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Hi all. sorry to bother you guys. I wrote a code a couple of years back that used Arpack in julia. I am updating it but I can´t run it. In my notes for it I have this: Arpacy\_jll must be the newer version. The older …

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## [Vector of functions](https://discourse.julialang.org/t/vector-of-functions/94811)

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**Author:** [@erlebach](https://discourse.julialang.org/u/erlebach)\
**Replies:** 5\
**Last updated:** [February 19, 2023, 11:54pm UTC](https://discourse.julialang.org/t/vector-of-functions/94811 "2023-02-19T23:54:36Z")

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I am trying to encode a Vector of functions. I wrote the following: # Does not work if I replace function by AbstractFunction a = Vector{Function}(undef, 5) for i in 1:5 a\[i\](t) = cos(i\*t) end I get the error: ER…

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## [Julia, detecting errors at compile time](https://discourse.julialang.org/t/julia-detecting-errors-at-compile-time/94762)

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**Author:** [@zeroexcuses](https://discourse.julialang.org/u/zeroexcuses)\
**Replies:** 6\
**Last updated:** [February 19, 2023, 11:52pm UTC](https://discourse.julialang.org/t/julia-detecting-errors-at-compile-time/94762 "2023-02-19T23:52:40Z")

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Setting aside Julia’s JIT runtime (even Java has a JIT, but javac, which does \*.java → jvm bytecode catches lots of errors): What is the most advanced tool for catching “no method/impl found for dispatch” errors “ahead …

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## [Deploy pages from branches](https://discourse.julialang.org/t/deploy-pages-from-branches/94274)

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**Author:** [@Rex\_Wang](https://discourse.julialang.org/u/Rex_Wang)\
**Replies:** 1\
**Last updated:** [February 19, 2023, 11:16pm UTC](https://discourse.julialang.org/t/deploy-pages-from-branches/94274 "2023-02-19T23:16:08Z")

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When translating the docs of a repo, it is natural to write codes in different branch. Documenter.jl provides two ways to deploy docs from different sources: Hosting Documentation · Documenter.jl Deploy by version num…

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## [FastSphericalHarmonics -- signal(4) Illegal instructions](https://discourse.julialang.org/t/fastsphericalharmonics-signal-4-illegal-instructions/94872)

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**Author:** [@aquarelleX332](https://discourse.julialang.org/u/aquarelleX332)\
**Replies:** 4\
**Last updated:** [February 19, 2023, 8:20pm UTC](https://discourse.julialang.org/t/fastsphericalharmonics-signal-4-illegal-instructions/94872 "2023-02-19T20:20:09Z")

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Hello, I am trying to reproduce the code in the “Example 2: visualize some modes” of the FastSphericalHarmonics.jl package. Here is the code after I add FastSphericalHarmonics and CairoMakie: using FastSphericalHarmon…

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## [Questions about JSONRPC.jl](https://discourse.julialang.org/t/questions-about-jsonrpc-jl/94745)

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**Author:** [@BambOoxX](https://discourse.julialang.org/u/BambOoxX)\
**Replies:** 1\
**Last updated:** [February 19, 2023, 5:22pm UTC](https://discourse.julialang.org/t/questions-about-jsonrpc-jl/94745 "2023-02-19T17:22:58Z")

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Context I have a custom RPC that works between julia and .NET (discussed in previous posts of mine), though it helped me to understand how this kind of communication works between different softs, it is totally handmade,…

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## [Checking if a value is contained in a MutableBinaryHeap?](https://discourse.julialang.org/t/checking-if-a-value-is-contained-in-a-mutablebinaryheap/82069)

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**Author:** [@Alejandro\_Quiaro\_San](https://discourse.julialang.org/u/Alejandro_Quiaro_San)\
**Replies:** 2\
**Last updated:** [February 19, 2023, 4:28pm UTC](https://discourse.julialang.org/t/checking-if-a-value-is-contained-in-a-mutablebinaryheap/82069 "2023-02-19T16:28:37Z")

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Hello guys, I need to test if a value is contained in a MutableBinaryHeap. I may have the following Tuple t: 6-element Vector{Tuple{Int64, Float64}}: (1, Inf) (2, Inf) (3, Inf) (4, Inf) (5, Inf) (6, Inf) For the…

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## [Using the Julia VScode extension on NixOS](https://discourse.julialang.org/t/using-the-julia-vscode-extension-on-nixos/94879)

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**Author:** [@Panadestein](https://discourse.julialang.org/u/Panadestein)\
**Replies:** 0\
**Last updated:** [February 19, 2023, 2:27pm UTC](https://discourse.julialang.org/t/using-the-julia-vscode-extension-on-nixos/94879 "2023-02-19T14:27:23Z")

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Similar questions have been asked a number of times in the forum, but mostly for Windows and Mac users. I am on the NixOS unstable flake, using Julia 1.8.5 and VScode 1.75.1. I am getting this error when I open any Julia…

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## [PackageCompiler EXE-File: How suppress extra DOS-Window beside GUI-Window (Gtk4)](https://discourse.julialang.org/t/packagecompiler-exe-file-how-suppress-extra-dos-window-beside-gui-window-gtk4/94846)

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**Author:** [@Ralf\_Dietrich](https://discourse.julialang.org/u/Ralf_Dietrich)\
**Replies:** 2\
**Last updated:** [February 19, 2023, 12:58pm UTC](https://discourse.julialang.org/t/packagecompiler-exe-file-how-suppress-extra-dos-window-beside-gui-window-gtk4/94846 "2023-02-19T12:58:35Z")

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Hello guys am experimenting with PackageCompiler at the moment and so far have always created EXE files that only run in a DOS window. This works so far also quite well. But now I have created a small GUI application w…

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## [Compile time: we can't find any impls for this multi dispatch fn?](https://discourse.julialang.org/t/compile-time-we-cant-find-any-impls-for-this-multi-dispatch-fn/94736)

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**Author:** [@zeroexcuses](https://discourse.julialang.org/u/zeroexcuses)\
**Replies:** 22\
**Last updated:** [February 19, 2023, 12:41pm UTC](https://discourse.julialang.org/t/compile-time-we-cant-find-any-impls-for-this-multi-dispatch-fn/94736 "2023-02-19T12:41:39Z")

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A bit of n00b question. Coming from a Scala / Rust background, I really really prefer compile time errors to runtime errors. Right now, my biggest frustration with Julia is that issues of “we can’t find an impl for thi…

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## [Flatten to a vector](https://discourse.julialang.org/t/flatten-to-a-vector/30408)

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**Author:** [@yakir12](https://discourse.julialang.org/u/yakir12)\
**Replies:** 26\
**Last updated:** [February 19, 2023, 11:55am UTC](https://discourse.julialang.org/t/flatten-to-a-vector/30408 "2023-02-19T11:55:41Z")

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Sorry @Raf, I can’t seem to find the documentation for this simple question: Is there a way for Flatten.flatten to return a Vector instead of a Tuple of the parameters? Right now I simply do: \[flatten(mystruct)...\] T…

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## [How to insert hooks into arbitrary places](https://discourse.julialang.org/t/how-to-insert-hooks-into-arbitrary-places/94841)

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**Author:** [@Lilith](https://discourse.julialang.org/u/Lilith)\
**Replies:** 4\
**Last updated:** [February 19, 2023, 1:00am UTC](https://discourse.julialang.org/t/how-to-insert-hooks-into-arbitrary-places/94841 "2023-02-19T01:00:01Z")

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I want to log every call of f(::T). I don’t know at design time what the implementation of f(::T) is, so I can’t reproduce it. One idea is to save m = which(f, Tuple{T}) and then insert a hook with f(x::T) = (log(x); in…

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## [Can I export some particular C bindings for GPU drivers to see?](https://discourse.julialang.org/t/can-i-export-some-particular-c-bindings-for-gpu-drivers-to-see/94852)

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**Author:** [@heyx3](https://discourse.julialang.org/u/heyx3)\
**Replies:** 0\
**Last updated:** [February 18, 2023, 8:58pm UTC](https://discourse.julialang.org/t/can-i-export-some-particular-c-bindings-for-gpu-drivers-to-see/94852 "2023-02-18T20:58:51Z")

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I’m trying to use ModernGL.jl to make a graphics program. However, my NVidia driver keeps using my integrated graphics instead of my discrete card. I can manually fix this in my driver settings, but I don’t want to have …

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## [Package License](https://discourse.julialang.org/t/package-license/7109)

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**Author:** [@RaulDurand](https://discourse.julialang.org/u/RaulDurand)\
**Replies:** 15\
**Last updated:** [February 18, 2023, 6:03pm UTC](https://discourse.julialang.org/t/package-license/7109 "2023-02-18T18:03:34Z")

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Julia and (most?) Julia packages are developed under the MIT license, which is a very permissive one. Is there any problem/concern (with Julia philosophy maybe, or any other restriction) to use a different license as GN…

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## [How to Create Bollinger Bands and Moving Average in Julia with Plots and DataFrame?](https://discourse.julialang.org/t/how-to-create-bollinger-bands-and-moving-average-in-julia-with-plots-and-dataframe/94794)

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**Author:** [@Freya\_the\_Goddess](https://discourse.julialang.org/u/Freya_the_Goddess)\
**Replies:** 2\
**Last updated:** [February 18, 2023, 5:06pm UTC](https://discourse.julialang.org/t/how-to-create-bollinger-bands-and-moving-average-in-julia-with-plots-and-dataframe/94794 "2023-02-18T17:06:50Z")

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Hi all, I want to plot a graph with Bollinger Bands and Moving Average indicator, the data will be loaded from CSV. Here are my conditions: I have this code to show graph and histogram from CSV data in Julia (previou…

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## [Automatically run unit tests](https://discourse.julialang.org/t/automatically-run-unit-tests/94534)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 7\
**Last updated:** [February 18, 2023, 3:43pm UTC](https://discourse.julialang.org/t/automatically-run-unit-tests/94534 "2023-02-18T15:43:52Z")

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Is there a way to automatically re-run the tests of a package when one of the dependencies gets updated? I have a large package that I did not touch a few months, and now I see three dependencies were updated such that …

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## [What is the most idiomatic way to implement bounds checking in \`getindex\` for arbitrary types?](https://discourse.julialang.org/t/what-is-the-most-idiomatic-way-to-implement-bounds-checking-in-getindex-for-arbitrary-types/94779)

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**Author:** [@loonatick-src](https://discourse.julialang.org/u/loonatick-src)\
**Replies:** 3\
**Last updated:** [February 18, 2023, 4:34am UTC](https://discourse.julialang.org/t/what-is-the-most-idiomatic-way-to-implement-bounds-checking-in-getindex-for-arbitrary-types/94779 "2023-02-18T04:34:47Z")

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Specifically, I have two main requirements in mind. It should throw BoundsError with complete information. The @inbounds macro should work as intended for this type, i.e. elide the bounds checking entirely Item 1 seem…

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## [Registry for docs CI not updated?](https://discourse.julialang.org/t/registry-for-docs-ci-not-updated/94807)

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**Author:** [@lmiq](https://discourse.julialang.org/u/lmiq)\
**Replies:** 1\
**Last updated:** [February 18, 2023, 1:32am UTC](https://discourse.julialang.org/t/registry-for-docs-ci-not-updated/94807 "2023-02-18T01:32:11Z")

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Is there any reason for the Julia registry to remain outdated in the Docs CI only? I’m having trouble with this run: update compat entry · m3g/ComplexMixtures.jl@606dc97 · GitHub Which fails with a compatibility proble…

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## [CSV.write writeshortest error](https://discourse.julialang.org/t/csv-write-writeshortest-error/90336)

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**Author:** [@compleat](https://discourse.julialang.org/u/compleat)\
**Replies:** 17\
**Last updated:** [February 18, 2023, 12:00am UTC](https://discourse.julialang.org/t/csv-write-writeshortest-error/90336 "2023-02-18T00:00:51Z")

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I have been trying for several days to save a dataframe and cannot seem to avoid the same recurring error. Here is the beginning of my file: df\_rtns6\[1:5,1:5\] Date AAPL\_Close ABT\_Close ADBE\_Close AIG\_Close String Flo…

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## [Can Julia optimize mutable static arrays to be allocated on the stack?](https://discourse.julialang.org/t/can-julia-optimize-mutable-static-arrays-to-be-allocated-on-the-stack/66360)

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**Author:** [@greatpet](https://discourse.julialang.org/u/greatpet)\
**Replies:** 9\
**Last updated:** [February 17, 2023, 9:54pm UTC](https://discourse.julialang.org/t/can-julia-optimize-mutable-static-arrays-to-be-allocated-on-the-stack/66360 "2023-02-17T21:54:23Z")

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According to the documentation of StaticArrays.jl, mutable static arrays are implemented as mutable structs and are allocated on the heap even though their sizes are known at compile time. Is Julia’s compiler able to det…

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## [Pass by reference of map typed struct(CxxWrap.jl)](https://discourse.julialang.org/t/pass-by-reference-of-map-typed-struct-cxxwrap-jl/82545)

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**Author:** [@kemu](https://discourse.julialang.org/u/kemu)\
**Replies:** 1\
**Last updated:** [February 17, 2023, 6:50pm UTC](https://discourse.julialang.org/t/pass-by-reference-of-map-typed-struct-cxxwrap-jl/82545 "2023-02-17T18:50:09Z")

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pass by reference of map typed struct(CxxWrap.jl) Hi, I’m trying to pass the argument by reference from Julia to C++. This argument is simple struct, so I used map\_type at wrap module difinition. I am having trouble …

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## [Call c++ functions using ccall](https://discourse.julialang.org/t/call-c-functions-using-ccall/94799)

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**Author:** [@linwaytin](https://discourse.julialang.org/u/linwaytin)\
**Replies:** 5\
**Last updated:** [February 17, 2023, 6:39pm UTC](https://discourse.julialang.org/t/call-c-functions-using-ccall/94799 "2023-02-17T18:39:28Z")

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I have a library in c++, from which I want to call some function. I have tried CxxWrap, which kind of work and seems not stable and I sometimes got segmentation faults. I tried to call the function using ccall((:myFunc,…

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## [With CxxWrap, method cannot return an usable complex number](https://discourse.julialang.org/t/with-cxxwrap-method-cannot-return-an-usable-complex-number/94801)

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**Author:** [@gdmsl](https://discourse.julialang.org/u/gdmsl)\
**Replies:** 0\
**Last updated:** [February 17, 2023, 5:57pm UTC](https://discourse.julialang.org/t/with-cxxwrap-method-cannot-return-an-usable-complex-number/94801 "2023-02-17T17:57:42Z")

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Hi, I am trying to use CxxWrap to wrap a C++ library. I am wrapping a type that has a method that returns a std::complex. I have also wrapped the std::complex type, since it is not already in the CxxWrap library. The p…

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## [Makie and PackageCompiler error on Windows](https://discourse.julialang.org/t/makie-and-packagecompiler-error-on-windows/92663)

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**Author:** [@skleinbo](https://discourse.julialang.org/u/skleinbo)\
**Replies:** 3\
**Last updated:** [February 17, 2023, 4:22pm UTC](https://discourse.julialang.org/t/makie-and-packagecompiler-error-on-windows/92663 "2023-02-17T16:22:29Z")

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In a fresh environment Julia Version 1.8.4 Commit 00177ebc4f (2022-12-23 21:32 UTC) Platform Info: OS: Windows (x86\_64-w64-mingw32) CPU: 4 × Intel(R) Core(TM) i5-6500 CPU @ 3.20GHz WORD\_SIZE: 64 LIBM: libopenlib…

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## [Can an overloaded vector operator be broadcast?](https://discourse.julialang.org/t/can-an-overloaded-vector-operator-be-broadcast/94651)

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**Author:** [@g2g](https://discourse.julialang.org/u/g2g)\
**Replies:** 15\
**Last updated:** [February 17, 2023, 4:35pm UTC](https://discourse.julialang.org/t/can-an-overloaded-vector-operator-be-broadcast/94651 "2023-02-17T16:35:51Z")

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I’m porting some projective geometric algebra (PGA) applications from ganja.js (JavaScript) to Julia+Makie. In the applications I’m porting (and I suspect in many other PGA applications) it would be convenient to be able…

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## [DataFrames Plot: Plot the year for the x-tick at x-axis](https://discourse.julialang.org/t/dataframes-plot-plot-the-year-for-the-x-tick-at-x-axis/94782)

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**Author:** [@Freya\_the\_Goddess](https://discourse.julialang.org/u/Freya_the_Goddess)\
**Replies:** 8\
**Last updated:** [February 17, 2023, 4:00pm UTC](https://discourse.julialang.org/t/dataframes-plot-plot-the-year-for-the-x-tick-at-x-axis/94782 "2023-02-17T16:00:54Z")

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Hi all, I am using the source of historical data from: Stock Market Indices - Investing.com I want to plot the price (graph plot) from the csv I downloaded (JKSE / Jakarta Stock Composite Index). But, the x-tick is nu…

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## [IRTools/Cassette question: Is it possible to replace everything with invokelatest?](https://discourse.julialang.org/t/irtools-cassette-question-is-it-possible-to-replace-everything-with-invokelatest/94785)

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**Author:** [@schlichtanders](https://discourse.julialang.org/u/schlichtanders)\
**Replies:** 4\
**Last updated:** [February 17, 2023, 1:41pm UTC](https://discourse.julialang.org/t/irtools-cassette-question-is-it-possible-to-replace-everything-with-invokelatest/94785 "2023-02-17T13:41:05Z")

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Hi there, I would like to build a rewriting system which ensures that everything will call the latest methods. This could be useful for developing long running applications like web servers. goal allinvokelatest() do …

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## [Which kernel is Jupyter running?](https://discourse.julialang.org/t/which-kernel-is-jupyter-running/93932)

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**Author:** [@stecrotti](https://discourse.julialang.org/u/stecrotti)\
**Replies:** 1\
**Last updated:** [February 17, 2023, 1:09pm UTC](https://discourse.julialang.org/t/which-kernel-is-jupyter-running/93932 "2023-02-17T13:09:25Z")

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Hi, I’ve set up several IJulia 1.8.0 kernels, a plain one, another with 4 threads, another with 10, and so on. I can start any of them without problems screenshot but once it’s up and going, there seems to be no infor…

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## [Makie surface not working with Observables](https://discourse.julialang.org/t/makie-surface-not-working-with-observables/94786)

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**Author:** [@AwesomeQuest](https://discourse.julialang.org/u/AwesomeQuest)\
**Replies:** 0\
**Last updated:** [February 17, 2023, 10:37am UTC](https://discourse.julialang.org/t/makie-surface-not-working-with-observables/94786 "2023-02-17T10:37:23Z")

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When I make a surface with Observables in Makie using GLMakie sep = Observable(.01) xlim = Observable(5) ylim = Observable(10) x = @lift(-$xlim:$sep:$xlim) y = @lift(-$ylim:$sep:$ylim) z = @lift(\[i\*j for i in $x, j in …

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## [Create Histogram of Monthly Return with CSV and DataFrames](https://discourse.julialang.org/t/create-histogram-of-monthly-return-with-csv-and-dataframes/94729)

<div class="topic-metadata">

**Author:** [@Freya\_the\_Goddess](https://discourse.julialang.org/u/Freya_the_Goddess)\
**Replies:** 6\
**Last updated:** [February 17, 2023, 8:49am UTC](https://discourse.julialang.org/t/create-histogram-of-monthly-return-with-csv-and-dataframes/94729 "2023-02-17T08:49:50Z")

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Hi all, I am reading this: and I want to plot a histogram for monthly return of a Shanghai Composite Index based on this code: using CSV, DataFrames #Read the CSV file and transform it into a DataFrame rai…

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