# \#kernel

**URL:** https://discourse.julialang.org/tag/kernel/614.md

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

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## [\[ANN\] Cruise.jl v0.3.0 : Game engine kernel for julia](https://discourse.julialang.org/t/ann-cruise-jl-v0-3-0-game-engine-kernel-for-julia/134121)

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**Author:** [@Gesee](https://discourse.julialang.org/u/Gesee)\
**Replies:** 0\
**Last updated:** [November 25, 2025, 7:43pm UTC](https://discourse.julialang.org/t/ann-cruise-jl-v0-3-0-game-engine-kernel-for-julia/134121 "2025-11-25T19:43:16Z")

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Hi everyone, Happy to announce the new version of my engine, Cruise.jl. It has now been reduced to a kernel and gained several meaningful features that were absolutely worth the wait. Installation Stable version (The p…

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## [Why is my kernel as slow in FP32 as in FP64 on A2000 Ada-based GPU?](https://discourse.julialang.org/t/why-is-my-kernel-as-slow-in-fp32-as-in-fp64-on-a2000-ada-based-gpu/126809)

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**Author:** [@Ludovic\_Dumoulin](https://discourse.julialang.org/u/Ludovic_Dumoulin)\
**Replies:** 10\
**Last updated:** [March 11, 2025, 2:39pm UTC](https://discourse.julialang.org/t/why-is-my-kernel-as-slow-in-fp32-as-in-fp64-on-a2000-ada-based-gpu/126809 "2025-03-11T14:39:58Z")

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Hello, I am new to Julia and I wanted to use Float32 to debug my code expecting it be faster as my gpu provide only 1/64 of its performance in Float64. I was surprised to see that using Float32 was almost as slow as Fl…

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## [Using Multivariate Posterior Samples as Prior in Julia’s Turing for MCMC](https://discourse.julialang.org/t/using-multivariate-posterior-samples-as-prior-in-julia-s-turing-for-mcmc/124698)

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**Author:** [@hinata235](https://discourse.julialang.org/u/hinata235)\
**Replies:** 0\
**Last updated:** [January 12, 2025, 2:59pm UTC](https://discourse.julialang.org/t/using-multivariate-posterior-samples-as-prior-in-julia-s-turing-for-mcmc/124698 "2025-01-12T14:59:11Z")

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Question: I would like to use posterior distribution samples obtained via MCMC for multivariate parameters of a certain model as the prior distribution when running MCMC on another dataset. Currently, for the univariat…

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## [How to Use a Distribution Estimated via Kernel Density Estimation (KDE) as a Prior in Turing.jl](https://discourse.julialang.org/t/how-to-use-a-distribution-estimated-via-kernel-density-estimation-kde-as-a-prior-in-turing-jl/124504)

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**Author:** [@hinata235](https://discourse.julialang.org/u/hinata235)\
**Replies:** 4\
**Last updated:** [January 12, 2025, 2:02pm UTC](https://discourse.julialang.org/t/how-to-use-a-distribution-estimated-via-kernel-density-estimation-kde-as-a-prior-in-turing-jl/124504 "2025-01-12T14:02:49Z")

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Background and Goal I have a set of discrete samples (e.g., from some existing dataset or posterior). I estimated a continuous distribution from these samples using a kernel density estimation (KDE) approach (such as vi…

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## [Sampling from a KDE object](https://discourse.julialang.org/t/sampling-from-a-kde-object/121604)

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**Author:** [@miguelborrero](https://discourse.julialang.org/u/miguelborrero)\
**Replies:** 4\
**Last updated:** [October 23, 2024, 8:54pm UTC](https://discourse.julialang.org/t/sampling-from-a-kde-object/121604 "2024-10-23T20:54:06Z")

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Hi there, I estimated the density for a variable of interest using the kde() function from KernelDensity.jl package. Is there not a built-in/efficient function that samples from this estimated density? Thanks a lot!

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## [How to make Quarto with Julia in VSCode work?](https://discourse.julialang.org/t/how-to-make-quarto-with-julia-in-vscode-work/111882)

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**Author:** [@Hugo](https://discourse.julialang.org/u/Hugo)\
**Replies:** 4\
**Last updated:** [March 27, 2024, 9:07pm UTC](https://discourse.julialang.org/t/how-to-make-quarto-with-julia-in-vscode-work/111882 "2024-03-27T21:07:02Z")

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I am facing difficulties trying to use Quarto in VSCode with Julia (again). I have asked a question here before (see this), but at the time I gave using Quarto in VSCode with Julia and simply used Quarto in RStudio with …

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## [Kernel random numbers generation entropy / randomness issues](https://discourse.julialang.org/t/kernel-random-numbers-generation-entropy-randomness-issues/105637)

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**Author:** [@ReWoP](https://discourse.julialang.org/u/ReWoP)\
**Replies:** 25\
**Last updated:** [November 3, 2023, 4:19pm UTC](https://discourse.julialang.org/t/kernel-random-numbers-generation-entropy-randomness-issues/105637 "2023-11-03T16:19:05Z")

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Hi all! I’m implementing with some algorithms in the GPU (CUDA) that are stochastic in nature, meaning that they rely on random numbers (namely uniformly distributed random numbers in \[0,1\]) to achieve results. When pr…

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## [Radial basis function kernel](https://discourse.julialang.org/t/radial-basis-function-kernel/102046)

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**Author:** [@josemanuel22](https://discourse.julialang.org/u/josemanuel22)\
**Replies:** 2\
**Last updated:** [July 25, 2023, 7:43am UTC](https://discourse.julialang.org/t/radial-basis-function-kernel/102046 "2023-07-25T07:43:27Z")

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Hello everyone, I am currently trying to code an MMD GAN (\[1705.08584\] MMD GAN: Towards Deeper Understanding of Moment Matching Network), but I would like to know if there is any package in Julia that directly implements…

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## [Error when using CUDA.dot() in kernel](https://discourse.julialang.org/t/error-when-using-cuda-dot-in-kernel/100476)

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**Author:** [@huiyuxie](https://discourse.julialang.org/u/huiyuxie)\
**Replies:** 2\
**Last updated:** [June 18, 2023, 5:13am UTC](https://discourse.julialang.org/t/error-when-using-cuda-dot-in-kernel/100476 "2023-06-18T05:13:27Z")

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Here is a very simple version of trying to compute dot product in GPU kernel. Having tried c\[i\] = transpose(a\[i, :\]) \* b\[:, i\] c\[i\] = CUDA.dot(a\[i, :\], b\[:, i\]) c\[i\] = CUBLAS.dot(4, a\[i, :\], b\[:, i\]) but all reported…

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## [Why is GPU kernel rand() not as "random" as CPU rand()?](https://discourse.julialang.org/t/why-is-gpu-kernel-rand-not-as-random-as-cpu-rand/98892)

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**Author:** [@ReWoP](https://discourse.julialang.org/u/ReWoP)\
**Replies:** 10\
**Last updated:** [May 17, 2023, 2:41am UTC](https://discourse.julialang.org/t/why-is-gpu-kernel-rand-not-as-random-as-cpu-rand/98892 "2023-05-17T02:41:53Z")

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Hi all, I’m implementing some optimization algorithms in the GPU (CUDA) that rely on, among other things, random numbers to set the exploration of the search space. I’m also comparing the results with the CPU implementa…

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## [GPs: sum of independent Kernels](https://discourse.julialang.org/t/gps-sum-of-independent-kernels/98542)

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**Author:** [@martincornejo](https://discourse.julialang.org/u/martincornejo)\
**Replies:** 2\
**Last updated:** [May 10, 2023, 8:00am UTC](https://discourse.julialang.org/t/gps-sum-of-independent-kernels/98542 "2023-05-10T08:00:58Z")

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The documentation of KernelFunctions.jl specifies many building blocks to define composite Kernels. But I can’t find a way to build a sum of independent Kernels, something similar to the KernelTensorProduct but with addi…

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## [Indexing in GPU kernel](https://discourse.julialang.org/t/indexing-in-gpu-kernel/96902)

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**Author:** [@shakedregev](https://discourse.julialang.org/u/shakedregev)\
**Replies:** 2\
**Last updated:** [March 31, 2023, 7:07pm UTC](https://discourse.julialang.org/t/indexing-in-gpu-kernel/96902 "2023-03-31T19:07:11Z")

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I’m building a custom GPU kernel and am having trouble indexing into a GPU vector. Q is a matrix stored in CSR format qrows - row pointers qcols - nonzero column indices qvals - nonzero values Here is a code snippet: …

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## [Change default IJulia kernel associated to a notebook](https://discourse.julialang.org/t/change-default-ijulia-kernel-associated-to-a-notebook/94055)

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**Author:** [@mocalvao](https://discourse.julialang.org/u/mocalvao)\
**Replies:** 2\
**Last updated:** [February 5, 2023, 11:26am UTC](https://discourse.julialang.org/t/change-default-ijulia-kernel-associated-to-a-notebook/94055 "2023-02-05T11:26:20Z")

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Hi there I cloned the git repo rethinking.jl for the Statistical Rethinking, 2nd. ed. book, in order to follow along with its notebooks. My currrent version of Julia is 1.8.3, but I still have older ones (such as 1.6.2,…

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## [What to do when command \`\`\`notebook()\`\`\` won't prompt a Jupyter installation?](https://discourse.julialang.org/t/what-to-do-when-command-notebook-wont-prompt-a-jupyter-installation/92897)

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**Author:** [@Hugo](https://discourse.julialang.org/u/Hugo)\
**Replies:** 2\
**Last updated:** [January 12, 2023, 11:01pm UTC](https://discourse.julialang.org/t/what-to-do-when-command-notebook-wont-prompt-a-jupyter-installation/92897 "2023-01-12T23:01:07Z")

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TL;DR: How to make Julia find the jupyter kernel so Quarto can run? I just installed a new version of Julia (1.8.5) and, given the problems I am dealing with, I assume the packages I had installed didn’t migrate to the …

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## [CUDA.jl - A Clear Example of Dynamic Parallelism](https://discourse.julialang.org/t/cuda-jl-a-clear-example-of-dynamic-parallelism/78856)

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**Author:** [@moukann](https://discourse.julialang.org/u/moukann)\
**Replies:** 6\
**Last updated:** [November 18, 2022, 8:24am UTC](https://discourse.julialang.org/t/cuda-jl-a-clear-example-of-dynamic-parallelism/78856 "2022-11-18T08:24:38Z")

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Hello all, I am not so experienced with CUDA.jl and I cannot find examples on concepts of GPU programming. Dynamic parallelism is a wonderful feature but I could not find an example to learn and apply to my program. Le…

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## [GPU-Kernel Profiling](https://discourse.julialang.org/t/gpu-kernel-profiling/87468)

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**Author:** [@Julien\_A](https://discourse.julialang.org/u/Julien_A)\
**Replies:** 1\
**Last updated:** [September 20, 2022, 6:47am UTC](https://discourse.julialang.org/t/gpu-kernel-profiling/87468 "2022-09-20T06:47:10Z")

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Hello, i’m currently profiling a Julia deep learning project, mainly executed on the GPU. Using nvprof i get following profiling result: ==7880== Profiling result: Type Time(%) Time Calls Avg…

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## [Changing Kernel to different Julia Versions](https://discourse.julialang.org/t/changing-kernel-to-different-julia-versions/85361)

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**Author:** [@donkeysaddle](https://discourse.julialang.org/u/donkeysaddle)\
**Replies:** 2\
**Last updated:** [August 7, 2022, 6:01pm UTC](https://discourse.julialang.org/t/changing-kernel-to-different-julia-versions/85361 "2022-08-07T18:01:47Z")

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Hi Gang! I have multiple versions of Julia installed on my Mac. Is there an easy way to switch from one to another while using Jupyter Notebook. I would have thought that they all just show up as options when I go to s…

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## [Juliacon21-gpu\_workshop kernel abstractions heat diffusion](https://discourse.julialang.org/t/juliacon21-gpu-workshop-kernel-abstractions-heat-diffusion/70048)

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**Author:** [@Ludovic\_Dumoulin](https://discourse.julialang.org/u/Ludovic_Dumoulin)\
**Replies:** 2\
**Last updated:** [October 20, 2021, 8:24am UTC](https://discourse.julialang.org/t/juliacon21-gpu-workshop-kernel-abstractions-heat-diffusion/70048 "2021-10-20T08:24:43Z")

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Hi, I am trying to reproduce the Juliacon21-gpu workshop and I am stuck at the last part of kernel abstractions. I wrote: @kernel function diffuse\_kabs\_lmem!(out, @Const(data), a, dt, dx, dy) i, j = @index(Global,…

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## [GPU-Kernel function for fast matrix multiplication using shared memory](https://discourse.julialang.org/t/gpu-kernel-function-for-fast-matrix-multiplication-using-shared-memory/66341)

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**Author:** [@DanielZ](https://discourse.julialang.org/u/DanielZ)\
**Replies:** 1\
**Last updated:** [August 13, 2021, 2:08pm UTC](https://discourse.julialang.org/t/gpu-kernel-function-for-fast-matrix-multiplication-using-shared-memory/66341 "2021-08-13T14:08:20Z")

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\[Copied from a Slack-Conversation:\] Me (Daniel): Hello, we try to implement a matrix multiplication in a kernel function using shared memory. However, our code in the kernel\_matmul\_fast function calculates a wrong resu…

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## [Trouble running IJulia (could not open file .julia/packages/IJulia/IDNmS ...)](https://discourse.julialang.org/t/trouble-running-ijulia-could-not-open-file-julia-packages-ijulia-idnms/62234)

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**Author:** [@srgree](https://discourse.julialang.org/u/srgree)\
**Replies:** 0\
**Last updated:** [June 1, 2021, 10:54pm UTC](https://discourse.julialang.org/t/trouble-running-ijulia-could-not-open-file-julia-packages-ijulia-idnms/62234 "2021-06-01T22:54:29Z")

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Hello, I recently updated IJulia and am now having trouble starting the kernel from jupyter notebook. From the Terminal, I run jupyter notebook, which opens up jupyter in my browser. (base) ➜ Non-markovian-simulation-…

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## [Weird behavior in @cuda kernel dispatch](https://discourse.julialang.org/t/weird-behavior-in-cuda-kernel-dispatch/55724)

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**Author:** [@Shuhua](https://discourse.julialang.org/u/Shuhua)\
**Replies:** 2\
**Last updated:** [February 22, 2021, 2:51am UTC](https://discourse.julialang.org/t/weird-behavior-in-cuda-kernel-dispatch/55724 "2021-02-22T02:51:21Z")

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Consider the following dummy kernel function that accepts an argument of type CuVector. julia\> using CUDA julia\> function my\_kernel(v::CuVector) nothing end my\_kernel (generic function with 1 method) …