# Latest

**URL:** https://discourse.julialang.org/latest.md?page=457

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

**Page:** 458

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## [How to copy Mathematica expression into a Julia function](https://discourse.julialang.org/t/how-to-copy-mathematica-expression-into-a-julia-function/97670)

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**Author:** [@roi.holtzman](https://discourse.julialang.org/u/roi.holtzman)\
**Replies:** 7\
**Last updated:** [March 16, 2024, 6:03am UTC](https://discourse.julialang.org/t/how-to-copy-mathematica-expression-into-a-julia-function/97670 "2024-03-16T06:03:13Z")

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Very similar questions were asked before in the discourse (see e.g. this, this, and this). Answers point to MathLink where one can plug an expression like this using MathLink sqx = W\`Sqrt\[x\]\` and then evaluate this fun…

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## [How to define the DAE using du\[\] style](https://discourse.julialang.org/t/how-to-define-the-dae-using-du-style/111392)

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**Author:** [@whucsu](https://discourse.julialang.org/u/whucsu)\
**Replies:** 6\
**Last updated:** [March 16, 2024, 12:58am UTC](https://discourse.julialang.org/t/how-to-define-the-dae-using-du-style/111392 "2024-03-16T00:58:03Z")

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here is another windkessel model in the simulation, from “The differential-algebraic Windkessel model with power as input” by Henry Pigot. I don’t know to define the DAE using Julia common package like DifferentialEqu…

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## [KrylovKit v0.7](https://discourse.julialang.org/t/krylovkit-v0-7/111688)

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**Author:** [@juthohaegeman](https://discourse.julialang.org/u/juthohaegeman)\
**Replies:** 0\
**Last updated:** [March 15, 2024, 11:21pm UTC](https://discourse.julialang.org/t/krylovkit-v0-7/111688 "2024-03-15T23:21:20Z")

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KrylovKit.jl v0.7 now depends on and uses VectorInterface.jl to define the vector-like behavior of the input vectors, rather than some minimal set of methods from Base and LinearAlgebra. The advantage is that many more t…

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## [SimpleITK via PythonCall not loading NumPy](https://discourse.julialang.org/t/simpleitk-via-pythoncall-not-loading-numpy/104034)

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**Author:** [@Dale\_James\_Black](https://discourse.julialang.org/u/Dale_James_Black)\
**Replies:** 10\
**Last updated:** [March 15, 2024, 10:32pm UTC](https://discourse.julialang.org/t/simpleitk-via-pythoncall-not-loading-numpy/104034 "2024-03-15T22:32:01Z")

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I am trying to use SimpleITK via PythonCall inside a Pluto notebook. I want to load a DICOM image and then convert it to a numpy array. The code to do this is straightforward and works in pure python, but with PythonCall…

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## [Job Position @ EnviTrace](https://discourse.julialang.org/t/job-position-envitrace/111682)

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**Author:** [@monty](https://discourse.julialang.org/u/monty)\
**Replies:** 0\
**Last updated:** [March 15, 2024, 8:58pm UTC](https://discourse.julialang.org/t/job-position-envitrace/111682 "2024-03-15T20:58:21Z")

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Our company (EnviTrace; https://envitrace.com) is seeking a quote for contract support to design Julia software and interactive web/mobile applications. The software will be deployed on the cloud. Interactive visualizat…

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## [Error when combining single row with multiple row CSV file into DataFrames](https://discourse.julialang.org/t/error-when-combining-single-row-with-multiple-row-csv-file-into-dataframes/111664)

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**Author:** [@phantom](https://discourse.julialang.org/u/phantom)\
**Replies:** 6\
**Last updated:** [March 15, 2024, 8:48pm UTC](https://discourse.julialang.org/t/error-when-combining-single-row-with-multiple-row-csv-file-into-dataframes/111664 "2024-03-15T20:48:29Z")

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Hi! I am combining several .csv files into DataFrames. Each file has uniform column numbers and data types. Everything works but when I try to combine a .csv file that contains a single row with one that contains mult…

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## [Rotating the axis label in GR makes the label go out of the plot](https://discourse.julialang.org/t/rotating-the-axis-label-in-gr-makes-the-label-go-out-of-the-plot/111672)

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**Author:** [@archisman](https://discourse.julialang.org/u/archisman)\
**Replies:** 1\
**Last updated:** [March 15, 2024, 8:41pm UTC](https://discourse.julialang.org/t/rotating-the-axis-label-in-gr-makes-the-label-go-out-of-the-plot/111672 "2024-03-15T20:41:45Z")

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Here is my code using Plots using LaTeXStrings a = randn(100,1); b = sin.(a); scatter(a,b,xlabel=L"x",ylabel=L"\\sin(x)", framestyle = :box, legend=false, yguidefontrotation = -90 ) The label “s…

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## [Is there a Julia equivalent of Matlab's Array(i) = Value for undefined indicies?](https://discourse.julialang.org/t/is-there-a-julia-equivalent-of-matlabs-array-i-value-for-undefined-indicies/111167)

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**Author:** [@MonkeyZK](https://discourse.julialang.org/u/MonkeyZK)\
**Replies:** 15\
**Last updated:** [March 15, 2024, 5:41pm UTC](https://discourse.julialang.org/t/is-there-a-julia-equivalent-of-matlabs-array-i-value-for-undefined-indicies/111167 "2024-03-15T17:41:44Z")

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As the title suggest I was curious if Julia base or LinearAlgebra had some existing equivalent to Matlab’s implementation of assigning values to a non-exisiting index: \>\> Array = \[\]; Array(3) = 3; Array(5) = 5; Array(3,…

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## [Fastest way of getting a long zero vector?](https://discourse.julialang.org/t/fastest-way-of-getting-a-long-zero-vector/111628)

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**Author:** [@PetrKryslUCSD](https://discourse.julialang.org/u/PetrKryslUCSD)\
**Replies:** 29\
**Last updated:** [March 15, 2024, 6:55pm UTC](https://discourse.julialang.org/t/fastest-way-of-getting-a-long-zero-vector/111628 "2024-03-15T18:55:48Z")

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I have these three ways of creating a zero vector. module m function zeroout(a) @inbounds Threads.@threads for k in eachindex(a) a\[k\] = 0.0 end end N = 1000000000 println("a = fill(0.0, N);") @time a =…

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## [Nonlinear Optimization with Many Constraints + Autodifferentiation: Which Julia Solution?](https://discourse.julialang.org/t/nonlinear-optimization-with-many-constraints-autodifferentiation-which-julia-solution/110678)

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**Author:** [@SebKrantz](https://discourse.julialang.org/u/SebKrantz)\
**Replies:** 23\
**Last updated:** [March 15, 2024, 6:42pm UTC](https://discourse.julialang.org/t/nonlinear-optimization-with-many-constraints-autodifferentiation-which-julia-solution/110678 "2024-03-15T18:42:18Z")

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I’m trying to rewrite a Matlab Package in Julia which solves a high-dimensional non-linear optimal transport problem in order to maximize economic welfare as predicted by a linked quantiative trade model. In particular, …

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## [Package SIIPExamples not found](https://discourse.julialang.org/t/package-siipexamples-not-found/111675)

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**Author:** [@Igor](https://discourse.julialang.org/u/Igor)\
**Replies:** 0\
**Last updated:** [March 15, 2024, 6:30pm UTC](https://discourse.julialang.org/t/package-siipexamples-not-found/111675 "2024-03-15T18:30:41Z")

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Package Package SIIPExamples not found not found using Package SIIPExamples not found Error Resolving package versions… ERROR: Unsatisfiable requirements detected for package PowerSystems \[bcd98974\]: PowerSystems …

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## [Stipple.select label](https://discourse.julialang.org/t/stipple-select-label/111674)

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**Author:** [@monty](https://discourse.julialang.org/u/monty)\
**Replies:** 0\
**Last updated:** [March 15, 2024, 6:08pm UTC](https://discourse.julialang.org/t/stipple-select-label/111674 "2024-03-15T18:08:29Z")

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Stipple.select(:dataset; options=:datanames, class="text-p", style="font-size: 11px;", color="white", bgcolor="bg-grey-8", popupcontentclass="bg-grey-9", label="Dataset:", labelcolor="orange") How can I change the font …

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## [Reinterpret byte to Float in julia](https://discourse.julialang.org/t/reinterpret-byte-to-float-in-julia/111670)

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**Author:** [@raman\_kumar](https://discourse.julialang.org/u/raman_kumar)\
**Replies:** 4\
**Last updated:** [March 15, 2024, 4:54pm UTC](https://discourse.julialang.org/t/reinterpret-byte-to-float-in-julia/111670 "2024-03-15T16:54:21Z")

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I have data of UInt8 type and i want to convert it into Float64. typeof(data) = Vector{UInt8} My data looks like :point\_right: data = read(f, N\_points \* 9) = UInt8\[0xdf, 0xfd, 0x5a, 0x80, 0x1c, 0x68, 0x86, 0x3f, 0xb6,…

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## [Flush stdout from workers](https://discourse.julialang.org/t/flush-stdout-from-workers/111669)

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**Author:** [@AAL](https://discourse.julialang.org/u/AAL)\
**Replies:** 0\
**Last updated:** [March 15, 2024, 4:38pm UTC](https://discourse.julialang.org/t/flush-stdout-from-workers/111669 "2024-03-15T16:38:48Z")

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I am running simulations in parallel processes that take many hours to run, so I print the number of replications to keep track of the progress. Here is a MWE: # test.jl using Distributed addprocs(2) @everywhere functi…

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## [Julia Slurm Output with MPI](https://discourse.julialang.org/t/julia-slurm-output-with-mpi/111635)

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**Author:** [@erny123](https://discourse.julialang.org/u/erny123)\
**Replies:** 0\
**Last updated:** [March 15, 2024, 12:32am UTC](https://discourse.julialang.org/t/julia-slurm-output-with-mpi/111635 "2024-03-15T00:32:42Z")

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I have a simple script to use in slurm and I’m having trouble understanding the output: #MPItest.jl using MPI println("Testing MPI") That I run on slurm with the following sbatch script: #!/bin/bash #SBATCH -p free…

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## [Solver for Elliptic PDE with Dirichlet and Neumann BCs](https://discourse.julialang.org/t/solver-for-elliptic-pde-with-dirichlet-and-neumann-bcs/111668)

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**Author:** [@mleprovost](https://discourse.julialang.org/u/mleprovost)\
**Replies:** 0\
**Last updated:** [March 15, 2024, 3:38pm UTC](https://discourse.julialang.org/t/solver-for-elliptic-pde-with-dirichlet-and-neumann-bcs/111668 "2024-03-15T15:38:43Z")

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Hello, I am interested in developing a finite difference solver for a 2D elliptic PDE (~ Darcy flow) from (https://arxiv.org/pdf/2205.09322.pdf). Do you have recommended packages to solve this PDE? The PDE is given by: …

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## [Any way to save variables to WorkSpace from the Debug Console in VSCode?](https://discourse.julialang.org/t/any-way-to-save-variables-to-workspace-from-the-debug-console-in-vscode/84933)

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**Author:** [@Nathan\_Boyer](https://discourse.julialang.org/u/Nathan_Boyer)\
**Replies:** 1\
**Last updated:** [March 15, 2024, 3:07pm UTC](https://discourse.julialang.org/t/any-way-to-save-variables-to-workspace-from-the-debug-console-in-vscode/84933 "2024-03-15T15:07:20Z")

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I seem to be able to edit existing workspace variable values from the debug console, but I am not able to define new variables. I want to be able to test and play with the next line after my breakpoint before actual…

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## [Initialize a package](https://discourse.julialang.org/t/initialize-a-package/111662)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 4\
**Last updated:** [March 15, 2024, 2:55pm UTC](https://discourse.julialang.org/t/initialize-a-package/111662 "2024-03-15T14:55:29Z")

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I have a package that needs some configuration data. Example data that is needed for tests is included in the package. But when I load the package the data path shall be set to joinpath(pwd(), "data"). Where could I cal…

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## [How to open .dlb extension file in Julia?](https://discourse.julialang.org/t/how-to-open-dlb-extension-file-in-julia/111644)

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**Author:** [@raman\_kumar](https://discourse.julialang.org/u/raman_kumar)\
**Replies:** 6\
**Last updated:** [March 15, 2024, 2:04pm UTC](https://discourse.julialang.org/t/how-to-open-dlb-extension-file-in-julia/111644 "2024-03-15T14:04:18Z")

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Hi , I want to open .dlb extension file using Julia and extract some data on it. I have .dlb file in my laptop. This data.6000.dlb file is in this tar. See Python code below :point\_down: def load\_data(directory, N\_r, …

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## [Readtable with DataFrame v0.21.3](https://discourse.julialang.org/t/readtable-with-dataframe-v0-21-3/42226)

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**Author:** [@Ernesto\_Diaz](https://discourse.julialang.org/u/Ernesto_Diaz)\
**Replies:** 4\
**Last updated:** [March 15, 2024, 2:03pm UTC](https://discourse.julialang.org/t/readtable-with-dataframe-v0-21-3/42226 "2024-03-15T14:03:09Z")

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I need read a .txt file. The structure: red=DataFrames.readtable(“I:/Julia/CHO/cho1.txt”,allowcomments=true,separator=’ ') worked with DataFrames v0.20.0 but not run with v0.21.3 (UndefVarError: readtable not defined) …

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## [How to create a string with observable values in GLMakie?](https://discourse.julialang.org/t/how-to-create-a-string-with-observable-values-in-glmakie/111525)

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**Author:** [@Luigi\_Marongiu](https://discourse.julialang.org/u/Luigi_Marongiu)\
**Replies:** 7\
**Last updated:** [March 15, 2024, 12:28pm UTC](https://discourse.julialang.org/t/how-to-create-a-string-with-observable-values-in-glmakie/111525 "2024-03-15T12:28:49Z")

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Hello, I am using GLMakie to make an interactive plot. I would like to make a label to a slider that shows the actual value of an observable. But how do I extract the value so that it can be rounded and displayed? In t…

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## [What is the difference between a variable that contains a function an a function?](https://discourse.julialang.org/t/what-is-the-difference-between-a-variable-that-contains-a-function-an-a-function/111652)

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**Author:** [@AwesomeQuest](https://discourse.julialang.org/u/AwesomeQuest)\
**Replies:** 4\
**Last updated:** [March 15, 2024, 9:44am UTC](https://discourse.julialang.org/t/what-is-the-difference-between-a-variable-that-contains-a-function-an-a-function/111652 "2024-03-15T09:44:11Z")

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Why is there a difference between f = x-\>5 and f(x) = 5 Why does the compiler treat these differently? Since if you run both of the above you get ERROR: cannot define function f; it already has a value But they bo…

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## [Manual type inference of hand-written IRCode](https://discourse.julialang.org/t/manual-type-inference-of-hand-written-ircode/106356)

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**Author:** [@Tomas\_Pevny](https://discourse.julialang.org/u/Tomas_Pevny)\
**Replies:** 10\
**Last updated:** [March 15, 2024, 8:02am UTC](https://discourse.julialang.org/t/manual-type-inference-of-hand-written-ircode/106356 "2024-03-15T08:02:19Z")

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Hello, i am trying to write something like Petite Zygote by manipulating Core.Compiler.IRCode to get sense, how it works. I am considering that as a part of survey, if I should show it to students, where the compiler in…

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## [Cannot change linestyle of line using attributes.linestyle in GLMakie](https://discourse.julialang.org/t/cannot-change-linestyle-of-line-using-attributes-linestyle-in-glmakie/111561)

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**Author:** [@oniehuis](https://discourse.julialang.org/u/oniehuis)\
**Replies:** 2\
**Last updated:** [March 15, 2024, 7:43am UTC](https://discourse.julialang.org/t/cannot-change-linestyle-of-line-using-attributes-linestyle-in-glmakie/111561 "2024-03-15T07:43:47Z")

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I want to change some attributes of lines that have already been drawn. I can change the color and line width by overwriting the values of line attributes.color and attributes.linewidth. However, I cannot change the line…

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## [NaNs during MCMC sampling?](https://discourse.julialang.org/t/nans-during-mcmc-sampling/111530)

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**Author:** [@rkube](https://discourse.julialang.org/u/rkube)\
**Replies:** 2\
**Last updated:** [March 15, 2024, 6:09am UTC](https://discourse.julialang.org/t/nans-during-mcmc-sampling/111530 "2024-03-15T06:09:40Z")

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Hi, I’m trying to perform model calibration with MCMC. When sampling from my posterior, I find that after about 1 sample, the MCMC sampler produces NaNs. I’m quiet new to MCMC sampling and am wondering whether there ar…

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## [How do I update github actions to Node.js 20?](https://discourse.julialang.org/t/how-do-i-update-github-actions-to-node-js-20/110536)

<div class="topic-metadata">

**Author:** [@ctkelley](https://discourse.julialang.org/u/ctkelley)\
**Replies:** 21\
**Last updated:** [March 14, 2024, 9:24pm UTC](https://discourse.julialang.org/t/how-do-i-update-github-actions-to-node-js-20/110536 "2024-03-14T21:24:27Z")

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I got a complaint from github about Node.jl 16 actions. It tells me Please update the following actions to use Node.js 20: actions/checkout@v3, julia-actions/setup-julia@latest. and points me to a link that does not h…

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## [Julia speed](https://discourse.julialang.org/t/julia-speed/111511)

<div class="topic-metadata">

**Author:** [@peDurand](https://discourse.julialang.org/u/peDurand)\
**Replies:** 28\
**Last updated:** [March 14, 2024, 8:17pm UTC](https://discourse.julialang.org/t/julia-speed/111511 "2024-03-14T20:17:00Z")

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Hello ! I teach computational Physics in a french university. I learn to my students to code in Modern Fortran and Python. I know that many people claim that Julia may be as fast as C or Fortran. So, I try a little test…

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## [From GLMakie v0.4.7 to GLMakie v0.9.9](https://discourse.julialang.org/t/from-glmakie-v0-4-7-to-glmakie-v0-9-9/111607)

<div class="topic-metadata">

**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 19\
**Last updated:** [March 14, 2024, 8:15pm UTC](https://discourse.julialang.org/t/from-glmakie-v0-4-7-to-glmakie-v0-9-9/111607 "2024-03-14T20:15:26Z")

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I am porting this code from GLMakie v0.4.7 to GLMakie v0.9.9. This means from Makie 0.15.3 to Makie 0.21.0 (I think). See also: Migrating from GLMakie 0.4.7 to current I tried this already two years ago and failed, bu…

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## [How to vectorize any function on the GPU with CUDA.jl?](https://discourse.julialang.org/t/how-to-vectorize-any-function-on-the-gpu-with-cuda-jl/111490)

<div class="topic-metadata">

**Author:** [@RYB](https://discourse.julialang.org/u/RYB)\
**Replies:** 3\
**Last updated:** [March 14, 2024, 7:01pm UTC](https://discourse.julialang.org/t/how-to-vectorize-any-function-on-the-gpu-with-cuda-jl/111490 "2024-03-14T19:01:38Z")

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Hello, I just started programming with CUDA.jl and would like to understand how to vectorize an operation in a GPU Kernel. In particular, given some function func(), is there a way to vectorize this function to apply el…

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## [Why GPU still OOM when using CUDA unified memory?](https://discourse.julialang.org/t/why-gpu-still-oom-when-using-cuda-unified-memory/111543)

<div class="topic-metadata">

**Author:** [@pxshen](https://discourse.julialang.org/u/pxshen)\
**Replies:** 6\
**Last updated:** [March 14, 2024, 6:44pm UTC](https://discourse.julialang.org/t/why-gpu-still-oom-when-using-cuda-unified-memory/111543 "2024-03-14T18:44:30Z")

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I’ve way more RAM than VRAM. Code runs fine on CPU. I thought using CUDA unified memory lets GPU tap system RAM but it still OOM. I’m asking bc I’m getting a new laptop for ML work. Does unified memory mean VRAM is no l…

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