# Latest

**URL:** https://discourse.julialang.org/latest.md?page=511

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

**Page:** 512

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## [Documenter.jl: @repl generated output differs from REPL](https://discourse.julialang.org/t/documenter-jl-repl-generated-output-differs-from-repl/108713)

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**Author:** [@matthias314](https://discourse.julialang.org/u/matthias314)\
**Replies:** 0\
**Last updated:** [January 12, 2024, 12:54am UTC](https://discourse.julialang.org/t/documenter-jl-repl-generated-output-differs-from-repl/108713 "2024-01-12T00:54:27Z")

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Let’s say I want to generate the REPL sequence julia\> f(x) = x f (generic function with 1 method) julia\> repr(f) "f" with a @repl block in Documenter.jl. If I write \`\`\`@repl f(x) = x repr(f) \`\`\` then I get the outpu…

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## [Parametric type construction with Parameters.jl fails](https://discourse.julialang.org/t/parametric-type-construction-with-parameters-jl-fails/108712)

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**Author:** [@apo383](https://discourse.julialang.org/u/apo383)\
**Replies:** 0\
**Last updated:** [January 12, 2024, 12:40am UTC](https://discourse.julialang.org/t/parametric-type-construction-with-parameters-jl-fails/108712 "2024-01-12T00:40:36Z")

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I like how @with\_kw can construct new type instances based on an existing one, and was successful with it until I made my struct parametric. First, the non-parametric version: using Parameters abstract type SomeTypes en…

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## [Loopless calculations](https://discourse.julialang.org/t/loopless-calculations/108628)

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**Author:** [@SergeantMike](https://discourse.julialang.org/u/SergeantMike)\
**Replies:** 12\
**Last updated:** [January 11, 2024, 11:27pm UTC](https://discourse.julialang.org/t/loopless-calculations/108628 "2024-01-11T23:27:28Z")

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As an Ecologist, I have a hard time wrapping my head around some of the more esoteric mathematical voo-doo that Julia does, and by that I mean pretty much anything more complicated than x+y=z. With that said, here’s wha…

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## [Race condition reading from Pipe](https://discourse.julialang.org/t/race-condition-reading-from-pipe/108707)

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**Author:** [@goerz](https://discourse.julialang.org/u/goerz)\
**Replies:** 1\
**Last updated:** [January 11, 2024, 11:10pm UTC](https://discourse.julialang.org/t/race-condition-reading-from-pipe/108707 "2024-01-11T23:10:24Z")

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Splitting this off from A \`tee\` option for \`IOCapture\` Does the following minimal working example for asynchronously reading data from a Pipe involve a race condition? using Random function main() pipe = Pipe() …

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## [Optimizating computational time of gradient on big linear UDEs](https://discourse.julialang.org/t/optimizating-computational-time-of-gradient-on-big-linear-udes/108645)

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**Author:** [@jarroyoe](https://discourse.julialang.org/u/jarroyoe)\
**Replies:** 11\
**Last updated:** [January 11, 2024, 10:28pm UTC](https://discourse.julialang.org/t/optimizating-computational-time-of-gradient-on-big-linear-udes/108645 "2024-01-11T22:28:25Z")

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I have an high-dimensional UDE model that includes a linear model. A MWE of the linear component of the model is: using ForwardDiff, DifferentialEquations, SciMLSensitivity trainingData = rand(100,4) p0 = rand(100,100)…

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## [Quadratures and cubatures with Dirac deltas](https://discourse.julialang.org/t/quadratures-and-cubatures-with-dirac-deltas/108683)

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**Author:** [@homocomputeris](https://discourse.julialang.org/u/homocomputeris)\
**Replies:** 11\
**Last updated:** [January 11, 2024, 6:46pm UTC](https://discourse.julialang.org/t/quadratures-and-cubatures-with-dirac-deltas/108683 "2024-01-11T18:46:46Z")

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Are there ways to compute cubatures of functions that include the Dirac delta function?

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## [How do I edit and test code changes in a package](https://discourse.julialang.org/t/how-do-i-edit-and-test-code-changes-in-a-package/108686)

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**Author:** [@Fenrir\_Sivar](https://discourse.julialang.org/u/Fenrir_Sivar)\
**Replies:** 7\
**Last updated:** [January 11, 2024, 8:31pm UTC](https://discourse.julialang.org/t/how-do-i-edit-and-test-code-changes-in-a-package/108686 "2024-01-11T20:31:01Z")

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I’m new to Julia and inherited a package from a work member (the only one with Julia experience around, left the company) I know how to install the package from my git repo, but I have no clue how to make my local chan…

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## [How to update function coefficients during run time](https://discourse.julialang.org/t/how-to-update-function-coefficients-during-run-time/108700)

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**Author:** [@alex-s-gardner](https://discourse.julialang.org/u/alex-s-gardner)\
**Replies:** 2\
**Last updated:** [January 11, 2024, 7:52pm UTC](https://discourse.julialang.org/t/how-to-update-function-coefficients-during-run-time/108700 "2024-01-11T19:52:52Z")

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I need to define a function: ddx(v) = ((v\[4\] + v\[6\]) / 2 - v\[5\]) / X.^ 2 where X is only known at run time and changes with each high level iteration of a loop. I’ve tried using @eval: @eval ddx(v) = ((v\[4\] + v\[6\]) /…

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## [How to get rid of the straight line?](https://discourse.julialang.org/t/how-to-get-rid-of-the-straight-line/108646)

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**Author:** [@kim1](https://discourse.julialang.org/u/kim1)\
**Replies:** 11\
**Last updated:** [January 11, 2024, 6:54pm UTC](https://discourse.julialang.org/t/how-to-get-rid-of-the-straight-line/108646 "2024-01-11T18:54:37Z")

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Hi guys this may sound weird but Im trying to plot my graph without the straight line that connecting to the curve in it, unfortunately I dont know how from my own equation. :joy: so that the result at the end i will get…

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## [How to return all variable values of a non-simplified system of equations from a structurally-simplified solution output](https://discourse.julialang.org/t/how-to-return-all-variable-values-of-a-non-simplified-system-of-equations-from-a-structurally-simplified-solution-output/107915)

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**Author:** [@chris-hampel-CA](https://discourse.julialang.org/u/chris-hampel-CA)\
**Replies:** 13\
**Last updated:** [January 11, 2024, 5:46pm UTC](https://discourse.julialang.org/t/how-to-return-all-variable-values-of-a-non-simplified-system-of-equations-from-a-structurally-simplified-solution-output/107915 "2024-01-11T17:46:00Z")

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Hello, I am using MTK to solve a system of algebraic nonlinear equations. Using structural\_simplify() helps make these types of problems much easier to solve. However, I have noticed an inefficiency when trying to retu…

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## [Update & call for community involvement on the Facebook group "Julia programming language"](https://discourse.julialang.org/t/update-call-for-community-involvement-on-the-facebook-group-julia-programming-language/108692)

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**Author:** [@Alex\_Tantos](https://discourse.julialang.org/u/Alex_Tantos)\
**Replies:** 2\
**Last updated:** [January 11, 2024, 5:22pm UTC](https://discourse.julialang.org/t/update-call-for-community-involvement-on-the-facebook-group-julia-programming-language/108692 "2024-01-11T17:22:47Z")

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I haven’t been using FB as frequently anymore, but today, entirely by accident, I noticed that over the past few weeks, I have been receiving notifications for new members in the Julia Programming Language group. At some…

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## [CURAND no longer makes CU Array for Complex Numbers](https://discourse.julialang.org/t/curand-no-longer-makes-cu-array-for-complex-numbers/108602)

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**Author:** [@Allan\_Baker](https://discourse.julialang.org/u/Allan_Baker)\
**Replies:** 6\
**Last updated:** [January 11, 2024, 5:13pm UTC](https://discourse.julialang.org/t/curand-no-longer-makes-cu-array-for-complex-numbers/108602 "2024-01-11T17:13:33Z")

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I feel I am doing something wrong. I’m not an expert in this GPU coding, so I was happy when I got this working maybe a year or two ago. I’m revisiting this code and it has stopped working. I have a vector of complex …

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## [Mapslices and @threads](https://discourse.julialang.org/t/mapslices-and-threads/28138)

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**Author:** [@Paul\_Soderlind](https://discourse.julialang.org/u/Paul_Soderlind)\
**Replies:** 4\
**Last updated:** [January 11, 2024, 4:57pm UTC](https://discourse.julialang.org/t/mapslices-and-threads/28138 "2024-01-11T16:57:17Z")

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I am fooling around with 1.30-rc1 and would like to understand how to make a call on mapslices threaded. Since mapslices can emulate a loop over an array dimension, it would nice to make that “loop” Threads.@threads. Do…

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## [JuliaCon 2024: CFP is now live!](https://discourse.julialang.org/t/juliacon-2024-cfp-is-now-live/106234)

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**Author:** [@ranjan](https://discourse.julialang.org/u/ranjan)\
**Replies:** 1\
**Last updated:** [January 11, 2024, 4:16pm UTC](https://discourse.julialang.org/t/juliacon-2024-cfp-is-now-live/106234 "2024-01-11T16:16:03Z")

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The JuliaCon 2024 Call for Proposals deadline is Wednesday, January 31 at 10:59 PM (UTC)! Submit your talk idea for the Global JuliaCon 2024 at the Philips Stadion in Eindhoven, NL on 9-13 July 2024.

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## [Learning rate decay in callback function](https://discourse.julialang.org/t/learning-rate-decay-in-callback-function/107859)

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**Author:** [@KianH](https://discourse.julialang.org/u/KianH)\
**Replies:** 3\
**Last updated:** [January 11, 2024, 4:10pm UTC](https://discourse.julialang.org/t/learning-rate-decay-in-callback-function/107859 "2024-01-11T16:10:06Z")

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I was wondering if there is a way to access the learning rate through a callback function when using Lux.jl and Optimization.jl packages. For instance in the line below: Optimization.solve(optprob, ADAM(1e-3), callback …

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## [FFTW with @parallel seg faults](https://discourse.julialang.org/t/fftw-with-parallel-seg-faults/10590)

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**Author:** [@mzilhao](https://discourse.julialang.org/u/mzilhao)\
**Replies:** 7\
**Last updated:** [January 11, 2024, 3:47pm UTC](https://discourse.julialang.org/t/fftw-with-parallel-seg-faults/10590 "2024-01-11T15:47:05Z")

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hi all, I have a code that I’m trying to trivially parallelize with @parallel, but I’m getting a strange segmentation fault that I’ve tracked down to a call to FFTW.plan\_r2r. This is the simplest example that reproduces…

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## [Package extention for Test allways loads](https://discourse.julialang.org/t/package-extention-for-test-allways-loads/108668)

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**Author:** [@Impressium](https://discourse.julialang.org/u/Impressium)\
**Replies:** 1\
**Last updated:** [January 11, 2024, 2:35pm UTC](https://discourse.julialang.org/t/package-extention-for-test-allways-loads/108668 "2024-01-11T14:35:51Z")

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Hi all :slight\_smile: I want to use some default during testing and put them in my packages in the ext foulder. In the Project.toml I put: \[weakdeps\] Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40" \[extensions\] TestExt…

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## [Converting Gtk.GtkAspectFrame to Gtk4.jl](https://discourse.julialang.org/t/converting-gtk-gtkaspectframe-to-gtk4-jl/108684)

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**Author:** [@xor0110](https://discourse.julialang.org/u/xor0110)\
**Replies:** 1\
**Last updated:** [January 11, 2024, 2:10pm UTC](https://discourse.julialang.org/t/converting-gtk-gtkaspectframe-to-gtk4-jl/108684 "2024-01-11T14:10:18Z")

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There seems to be a few subtle changes between Gtk.jl to Gtk4.jl that I’m just not able to figure out by myself. Perhaps anyone has a clue? In Gtk there’s a af = GtkAspectFrame("label", 0.5, 0.5, 4/3), that you can then…

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## [Using and understanding multi-threading](https://discourse.julialang.org/t/using-and-understanding-multi-threading/108682)

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**Author:** [@Andrea\_Vigliotti](https://discourse.julialang.org/u/Andrea_Vigliotti)\
**Replies:** 1\
**Last updated:** [January 11, 2024, 2:01pm UTC](https://discourse.julialang.org/t/using-and-understanding-multi-threading/108682 "2024-01-11T14:01:30Z")

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so, I am trying to understand how multi threading works, I started julia as julia -t 16 on a 32 cores node where I reserved 8, then I run the example from the documentation here these are the lines function sum\_single(a…

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## [Using Polyester.jl with ChunkSplitters.jl](https://discourse.julialang.org/t/using-polyester-jl-with-chunksplitters-jl/108528)

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**Author:** [@Bruno\_Amorim](https://discourse.julialang.org/u/Bruno_Amorim)\
**Replies:** 4\
**Last updated:** [January 11, 2024, 1:33pm UTC](https://discourse.julialang.org/t/using-polyester-jl-with-chunksplitters-jl/108528 "2024-01-11T13:33:46Z")

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I am trying to paralelize a function, where I have some quantity a that I split in chunks and paralelize over the differente chunks. After that I combine the results obtained from all chunks. An example of this would be …

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## [Parallel PyJulia](https://discourse.julialang.org/t/parallel-pyjulia/108680)

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**Author:** [@Bart\_van\_de\_Lint](https://discourse.julialang.org/u/Bart_van_de_Lint)\
**Replies:** 0\
**Last updated:** [January 11, 2024, 12:57pm UTC](https://discourse.julialang.org/t/parallel-pyjulia/108680 "2024-01-11T12:57:00Z")

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I am trying to train a RL model for controlling a kite. I am using python for training, and julia for the simulation. I want to speed up training using parallel deep RL. When trying to run julia functions from python in …

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## [Importing only specific lines from large csv file](https://discourse.julialang.org/t/importing-only-specific-lines-from-large-csv-file/108672)

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**Author:** [@aris](https://discourse.julialang.org/u/aris)\
**Replies:** 6\
**Last updated:** [January 11, 2024, 12:23pm UTC](https://discourse.julialang.org/t/importing-only-specific-lines-from-large-csv-file/108672 "2024-01-11T12:23:05Z")

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Greetings everyone, I am dealing with a very large CSV file, and I would like to only read specific parts of it and import them as a matrix. Effectively, I want something like: using DelimitedFiles data = readdlm("myf…

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## [\[ANN\] Announcing MusicTheory.jl](https://discourse.julialang.org/t/ann-announcing-musictheory-jl/108444)

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**Author:** [@dpsanders](https://discourse.julialang.org/u/dpsanders)\
**Replies:** 31\
**Last updated:** [January 11, 2024, 12:07pm UTC](https://discourse.julialang.org/t/ann-announcing-musictheory-jl/108444 "2024-01-11T12:07:51Z")

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MusicTheory.jl I’m happy to announce the new package MusicTheory.jl. The goal of the package is to provide a foundation for representing musical objects in a Julian way. The main challenge has been to find the right ab…

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## [Substantial increase in time in copying an instantiated broadcasted object vs a non-instantiated one](https://discourse.julialang.org/t/substantial-increase-in-time-in-copying-an-instantiated-broadcasted-object-vs-a-non-instantiated-one/108673)

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**Author:** [@jishnub](https://discourse.julialang.org/u/jishnub)\
**Replies:** 2\
**Last updated:** [January 11, 2024, 11:49am UTC](https://discourse.julialang.org/t/substantial-increase-in-time-in-copying-an-instantiated-broadcasted-object-vs-a-non-instantiated-one/108673 "2024-01-11T11:49:58Z")

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I’m trying to understand the difference in performance here: julia\> using LinearAlgebra julia\> n=40; U = UpperTriangular(rand(n,n)); C = similar(U); B = Broadcast.broadcasted(\*, 2.0, U); julia\> @btime copyto!($C, $B);…

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## [Julia crashing with jfptr\_task\_done\_hook\_75249.1](https://discourse.julialang.org/t/julia-crashing-with-jfptr-task-done-hook-75249-1/108676)

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**Author:** [@eveningsilverfox](https://discourse.julialang.org/u/eveningsilverfox)\
**Replies:** 1\
**Last updated:** [January 11, 2024, 11:35am UTC](https://discourse.julialang.org/t/julia-crashing-with-jfptr-task-done-hook-75249-1/108676 "2024-01-11T11:35:54Z")

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My julia code is crashing with the following error. RAM usage stays at a low value throughout, around 6/64GB. jfptr\_task\_done\_hook\_75249.1 at /home/aritra/julia-1.10.0/lib/julia/sys.so (unknown line) \_jl\_invoke at /cac…

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## [Setting up worker local buffers when using Distributed.jl](https://discourse.julialang.org/t/setting-up-worker-local-buffers-when-using-distributed-jl/108671)

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**Author:** [@RomeoV](https://discourse.julialang.org/u/RomeoV)\
**Replies:** 2\
**Last updated:** [January 11, 2024, 11:20am UTC](https://discourse.julialang.org/t/setting-up-worker-local-buffers-when-using-distributed-jl/108671 "2024-01-11T11:20:10Z")

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Hello all, I am in the process of incrementally optimizing an algorithm, having focused first on single-core performance, then threading, and now want to scale to Distributed workers. One key element of my optimization…

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## [Weird error in Flux model](https://discourse.julialang.org/t/weird-error-in-flux-model/108650)

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**Author:** [@artp96](https://discourse.julialang.org/u/artp96)\
**Replies:** 4\
**Last updated:** [January 11, 2024, 11:15am UTC](https://discourse.julialang.org/t/weird-error-in-flux-model/108650 "2024-01-11T11:15:29Z")

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I hate to blindly dump but I’m getting a weird error with this code. I’ve tried looking for something similar, and I’ve spent some time trying to debug it and even asked GPT-4 but I’m stumped. using cuDNN, Flux, CUDA h …

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## [How to change specific parameter in DifferentialEquations CallbackSet?](https://discourse.julialang.org/t/how-to-change-specific-parameter-in-differentialequations-callbackset/108378)

<div class="topic-metadata">

**Author:** [@Luigi\_Marongiu](https://discourse.julialang.org/u/Luigi_Marongiu)\
**Replies:** 7\
**Last updated:** [January 11, 2024, 11:02am UTC](https://discourse.julialang.org/t/how-to-change-specific-parameter-in-differentialequations-callbackset/108378 "2024-01-11T11:02:05Z")

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Hello, I am trying to run a simulation of a bacterial population with Julia. I set a function that takes one parameter (growth rate, mu) that should change at a specific time point (t\_in). I set the CallbackSet for the…

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## [Sampling (no inference) from a mixture model (compound probability distribution)](https://discourse.julialang.org/t/sampling-no-inference-from-a-mixture-model-compound-probability-distribution/108637)

<div class="topic-metadata">

**Author:** [@adomasbaliuka](https://discourse.julialang.org/u/adomasbaliuka)\
**Replies:** 3\
**Last updated:** [January 11, 2024, 10:09am UTC](https://discourse.julialang.org/t/sampling-no-inference-from-a-mixture-model-compound-probability-distribution/108637 "2024-01-11T10:09:15Z")

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I’ve never used Turing before and don’t have a lot of statistics knowledge but I’d love to be able to do this kind of thing anyway: I don’t have any data. I only want to compute the expectation value of a somewhat compl…

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## [How to start Pluto with a specified notebook?](https://discourse.julialang.org/t/how-to-start-pluto-with-a-specified-notebook/108665)

<div class="topic-metadata">

**Author:** [@ddrake](https://discourse.julialang.org/u/ddrake)\
**Replies:** 1\
**Last updated:** [January 11, 2024, 9:42am UTC](https://discourse.julialang.org/t/how-to-start-pluto-with-a-specified-notebook/108665 "2024-01-11T09:42:24Z")

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I have a Pluto notebook source file – say, my\_notebook.jl and would like to start the notebook. I’d expect something like this would work: $ julia -e 'using Pluto; Pluto.run("my\_notebook.jl")' but of course it doesn’t.…

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