# Latest

**URL:** https://discourse.julialang.org/latest.md?page=423

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

**Page:** 424

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## [Are \`Int64\` and \`Float64\` of the same type?](https://discourse.julialang.org/t/are-int64-and-float64-of-the-same-type/113574)

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**Author:** [@Lilith](https://discourse.julialang.org/u/Lilith)\
**Replies:** 5\
**Last updated:** [April 27, 2024, 10:22pm UTC](https://discourse.julialang.org/t/are-int64-and-float64-of-the-same-type/113574 "2024-04-27T22:22:46Z")

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typeof(Int64) and typeof(Float64) are both DataType, but Int64 isa Type{Int64} while !(Float64 isa Type{Int64}) and I would expect nothing besides the type of a value be utilized in the isa opperation. So I ask, are Int6…

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## [DataFrames: obtaining the subset of rows by a set of values](https://discourse.julialang.org/t/dataframes-obtaining-the-subset-of-rows-by-a-set-of-values/15923)

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**Author:** [@Luis\_de\_Sousa](https://discourse.julialang.org/u/Luis_de_Sousa)\
**Replies:** 45\
**Last updated:** [April 27, 2024, 9:32pm UTC](https://discourse.julialang.org/t/dataframes-obtaining-the-subset-of-rows-by-a-set-of-values/15923 "2024-04-27T21:32:33Z")

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Hi everyone, I would like to perform an operation similar to the SQL SELECT \* FROM table WHERE col IN ("1","2","3") on a DataFrame. I have an array with a few strings that I wish to use in this selection. From what I ha…

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## [Replacing brackets in a string](https://discourse.julialang.org/t/replacing-brackets-in-a-string/85478)

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**Author:** [@james3](https://discourse.julialang.org/u/james3)\
**Replies:** 7\
**Last updated:** [April 27, 2024, 8:53pm UTC](https://discourse.julialang.org/t/replacing-brackets-in-a-string/85478 "2024-04-27T20:53:37Z")

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I have a string such as str = "MyFunction\[x\] = ...", where x is a value. How do I replace the square brackets with parentheses such that str contains "MyFunction(x) = ..."? There can be may different values x, and in my …

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## [Lambda Systems](https://discourse.julialang.org/t/lambda-systems/113572)

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**Author:** [@avishipoddar](https://discourse.julialang.org/u/avishipoddar)\
**Replies:** 6\
**Last updated:** [April 27, 2024, 7:41pm UTC](https://discourse.julialang.org/t/lambda-systems/113572 "2024-04-27T19:41:02Z")

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I am trying to simulate a 3-level lambda system. I have defined the operators such as sigma\_ee, sigma\_es, sigma\_eg, etc. as 3-level matrices. To build the Hamiltonian as an MPO, do I use spin-1?

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## [\[ANN\] Lux.jl: Explicitly Parameterized Neural Networks in Julia](https://discourse.julialang.org/t/ann-lux-jl-explicitly-parameterized-neural-networks-in-julia/81689)

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**Author:** [@avikpal](https://discourse.julialang.org/u/avikpal)\
**Replies:** 49\
**Last updated:** [April 16, 2024, 4:03pm UTC](https://discourse.julialang.org/t/ann-lux-jl-explicitly-parameterized-neural-networks-in-julia/81689 "2024-04-16T16:03:50Z")

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Lux is a new Julia deep learning framework that decouples models and parameterization using deeply nested named tuples. Functional Layer API – Pure Functions and Deterministic Function Calls. No more implicit parameter…

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## [How to do multi-dimension integration with BigFloat?](https://discourse.julialang.org/t/how-to-do-multi-dimension-integration-with-bigfloat/113485)

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**Author:** [@baizhan](https://discourse.julialang.org/u/baizhan)\
**Replies:** 2\
**Last updated:** [April 27, 2024, 3:59pm UTC](https://discourse.julialang.org/t/how-to-do-multi-dimension-integration-with-bigfloat/113485 "2024-04-27T15:59:29Z")

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Hello, I want to calculate a multiple dimension integration, and I have to use high precision float. I have tried HCubature, which is a pure-julia implementation of integration. But when I use BigFloat as input, it wi…

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## [Help using CUDA to exponentiate Matrix](https://discourse.julialang.org/t/help-using-cuda-to-exponentiate-matrix/113548)

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**Author:** [@ShaswataRoy](https://discourse.julialang.org/u/ShaswataRoy)\
**Replies:** 3\
**Last updated:** [April 27, 2024, 2:46pm UTC](https://discourse.julialang.org/t/help-using-cuda-to-exponentiate-matrix/113548 "2024-04-27T14:46:14Z")

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I am trying to use CUDA to speed up the process of finding the exponential of a matrix. For some reason, all the steps are fast except the code written inside a loop using LinearAlgebra using SparseArrays using CUDA us…

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## [How to display a sparse array on the REPL?](https://discourse.julialang.org/t/how-to-display-a-sparse-array-on-the-repl/113565)

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**Author:** [@WuSiren](https://discourse.julialang.org/u/WuSiren)\
**Replies:** 5\
**Last updated:** [April 27, 2024, 1:49pm UTC](https://discourse.julialang.org/t/how-to-display-a-sparse-array-on-the-repl/113565 "2024-04-27T13:49:07Z")

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If I construct a sparse matrix on the REPL, it can directly display the distribution of non-zero elements of the matrix: julia\> using SparseArrays julia\> sparse(round.(rand(5,5))) 5×5 SparseMatrixCSC{Float64, Int64} wi…

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## [\[ANN\] Kroki.jl v1.0.0](https://discourse.julialang.org/t/ann-kroki-jl-v1-0-0/113562)

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**Author:** [@bauglir](https://discourse.julialang.org/u/bauglir)\
**Replies:** 0\
**Last updated:** [April 27, 2024, 1:08pm UTC](https://discourse.julialang.org/t/ann-kroki-jl-v1-0-0/113562 "2024-04-27T13:08:14Z")

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It has been a while since an update (close to two years). This is partially due to there not being too much to add to the package as it’s primarily a wrapper around a service, but it also means that the API is quite stab…

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## [Connect points in for loop](https://discourse.julialang.org/t/connect-points-in-for-loop/113429)

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**Author:** [@Sharara](https://discourse.julialang.org/u/Sharara)\
**Replies:** 15\
**Last updated:** [April 27, 2024, 12:00pm UTC](https://discourse.julialang.org/t/connect-points-in-for-loop/113429 "2024-04-27T12:00:02Z")

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Dear all I am using PlotlyJS (I need its interactivity) it is my code: k1 = equ1 k2 = equ2 k3 = equ3 k4 = equ4 push!(k1\_x, real(k1)) push!(k1\_y, imag(k1)) push!(k2\_x, real(k2)) push!(k2\_y, imag(k2)) push!(k3\_x, real(…

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## [Behavior of \\circ\<tab\>](https://discourse.julialang.org/t/behavior-of-circ-tab/113560)

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**Author:** [@d\_b](https://discourse.julialang.org/u/d_b)\
**Replies:** 2\
**Last updated:** [April 27, 2024, 10:24am UTC](https://discourse.julialang.org/t/behavior-of-circ-tab/113560 "2024-04-27T10:24:52Z")

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Inside “manual/functions” under “Function composition and piping”, the first example of using \\circ\<tab\> is julia\> (sqrt \\circ\<tab\> +)(3, 6) which evaluates to 3.0. However, when I try to do the same thing with \\sqrt\<t…

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## [Is it possible to preserve compilation cache from julia process to julia process?](https://discourse.julialang.org/t/is-it-possible-to-preserve-compilation-cache-from-julia-process-to-julia-process/113488)

<div class="topic-metadata">

**Author:** [@schlichtanders](https://discourse.julialang.org/u/schlichtanders)\
**Replies:** 9\
**Last updated:** [April 27, 2024, 1:47am UTC](https://discourse.julialang.org/t/is-it-possible-to-preserve-compilation-cache-from-julia-process-to-julia-process/113488 "2024-04-27T01:47:12Z")

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Hi there, my aim is to speed up my julia development environment. I am already using \_\_precompile\_\_(false) for my developed package and Revise as much as possible, but if the julia process restarts, it really takes long…

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## [Semantics of constant folding for type constructors](https://discourse.julialang.org/t/semantics-of-constant-folding-for-type-constructors/113528)

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**Author:** [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Replies:** 2\
**Last updated:** [April 27, 2024, 12:27am UTC](https://discourse.julialang.org/t/semantics-of-constant-folding-for-type-constructors/113528 "2024-04-27T00:27:27Z")

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I would like to expose an API in a package to the users as a simple set of parametric (singleton) types, with internally calculated parameters, using the smallest set of symbols as possible, without exposing type constru…

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## [Does the Julia community suffer from the “Lisp curse” (whatever it means)?](https://discourse.julialang.org/t/does-the-julia-community-suffer-from-the-lisp-curse-whatever-it-means/102852)

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**Author:** [@Tarny\_GG\_Channie](https://discourse.julialang.org/u/Tarny_GG_Channie)\
**Replies:** 19\
**Last updated:** [April 27, 2024, 12:03am UTC](https://discourse.julialang.org/t/does-the-julia-community-suffer-from-the-lisp-curse-whatever-it-means/102852 "2024-04-27T00:03:27Z")

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The Lisp curse is that the more expressive, powerful Lisp language doesn’t really get popular like the less expressive ones, maybe because of the lack of standardization, maybe because it’s easier to mess up? Maybe becau…

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## [My script fails at \`using\`](https://discourse.julialang.org/t/my-script-fails-at-using/113540)

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**Author:** [@TimG](https://discourse.julialang.org/u/TimG)\
**Replies:** 2\
**Last updated:** [April 26, 2024, 9:48pm UTC](https://discourse.julialang.org/t/my-script-fails-at-using/113540 "2024-04-26T21:48:08Z")

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I don’t understand environments. :worried: I’ve been avoiding trying to understand them for a while and just using Pkg.add willi-nilli. However, this morning I started getting new and unexpected issues without seeming…

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## [Any qualifier in CUDA.jl like \`\_\_device\_\_\` in CUDA/C++?](https://discourse.julialang.org/t/any-qualifier-in-cuda-jl-like-device-in-cuda-c/113517)

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**Author:** [@huiyuxie](https://discourse.julialang.org/u/huiyuxie)\
**Replies:** 6\
**Last updated:** [April 26, 2024, 4:20pm UTC](https://discourse.julialang.org/t/any-qualifier-in-cuda-jl-like-device-in-cuda-c/113517 "2024-04-26T16:20:51Z")

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Hi all! I was wondering is there any qualifier in CUDA.jl like \_\_device\_\_ in CUDA/C++ to calling a function from device to make sure the function call is not falling back to CPU. For example, using CUDA function gpu\_a…

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## [Request for Org/Pkg Logos/Graphics for Online Store / JuliaCon](https://discourse.julialang.org/t/request-for-org-pkg-logos-graphics-for-online-store-juliacon/113240)

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**Author:** [@rayegun](https://discourse.julialang.org/u/rayegun)\
**Replies:** 4\
**Last updated:** [April 26, 2024, 3:59pm UTC](https://discourse.julialang.org/t/request-for-org-pkg-logos-graphics-for-online-store-juliacon/113240 "2024-04-26T15:59:11Z")

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Hi folks! The JuliaCon Organizing Committee is working to set up a new online store for Julia-related merchandise, as well as getting ready for merchandise @ JuliaCon 2024. If you have a logo for your Julia organizatio…

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## [Create grouped dataframe by properties of a given column?](https://discourse.julialang.org/t/create-grouped-dataframe-by-properties-of-a-given-column/113360)

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**Author:** [@phantom](https://discourse.julialang.org/u/phantom)\
**Replies:** 9\
**Last updated:** [April 26, 2024, 3:26pm UTC](https://discourse.julialang.org/t/create-grouped-dataframe-by-properties-of-a-given-column/113360 "2024-04-26T15:26:38Z")

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Hi just wondering if there a way to group a DataFrame by properties within a column. E.g. Suppose julia\> df = DataFrame(date = Date(2024,3,25): Day(1):Date(2024,4,5)) 12×1 DataFrame Row │ date │ Date …

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## [Plots (plotly) multiple series or line labels in legend](https://discourse.julialang.org/t/plots-plotly-multiple-series-or-line-labels-in-legend/13001)

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**Author:** [@iwelch](https://discourse.julialang.org/u/iwelch)\
**Replies:** 3\
**Last updated:** [April 26, 2024, 3:24pm UTC](https://discourse.julialang.org/t/plots-plotly-multiple-series-or-line-labels-in-legend/13001 "2024-04-26T15:24:04Z")

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how does one label two lines? using Plots; pyplot() plot(Plots.fakedata(50,2), w=3, labels=\[ "a", "b" \]) the blue line is not labeled “a” and the red line is not labeled “b” . PS: Overview · Plots writes “if label is …

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## [Best free SDP, JuMP supported solvers?](https://discourse.julialang.org/t/best-free-sdp-jump-supported-solvers/102413)

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**Author:** [@nlaws](https://discourse.julialang.org/u/nlaws)\
**Replies:** 8\
**Last updated:** [April 26, 2024, 3:01pm UTC](https://discourse.julialang.org/t/best-free-sdp-jump-supported-solvers/102413 "2024-04-26T15:01:41Z")

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There are quite a few free SDP solvers listed in the supported JuMP solvers. I’m wondering (even if just anecdotally) what other’s experiences are like and what folks have found to work well? I have tried maybe half of t…

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## [Try-Catch online help](https://discourse.julialang.org/t/try-catch-online-help/113532)

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**Author:** [@Jake](https://discourse.julialang.org/u/Jake)\
**Replies:** 2\
**Last updated:** [April 26, 2024, 1:56pm UTC](https://discourse.julialang.org/t/try-catch-online-help/113532 "2024-04-26T13:56:47Z")

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Within the Julia REPL I typed ?try. I found no reference to the finally clause. Same for ?catch. Typing ?finally does give information but the help on try should inform the user that the finally option exists. Then w…

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## [Julia / OHDSI Health RSE at Tufts CTSI (Fully Remote, Junior Level, U.S. Only)](https://discourse.julialang.org/t/julia-ohdsi-health-rse-at-tufts-ctsi-fully-remote-junior-level-u-s-only/113433)

<div class="topic-metadata">

**Author:** [@cce](https://discourse.julialang.org/u/cce)\
**Replies:** 3\
**Last updated:** [April 26, 2024, 1:43pm UTC](https://discourse.julialang.org/t/julia-ohdsi-health-rse-at-tufts-ctsi-fully-remote-junior-level-u-s-only/113433 "2024-04-26T13:43:39Z")

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Tufts CTSI Informatics is seeking a clinical data analyst / junior research software engineer. We are one of 60 NIH CTSA awardees. This role is primarily supporting our researchers with cohort discoveries, chart abstrac…

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## [AoG/Makie: Axis sorted in alphabetical order](https://discourse.julialang.org/t/aog-makie-axis-sorted-in-alphabetical-order/113527)

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**Author:** [@gruemelmonster](https://discourse.julialang.org/u/gruemelmonster)\
**Replies:** 2\
**Last updated:** [April 26, 2024, 12:39pm UTC](https://discourse.julialang.org/t/aog-makie-axis-sorted-in-alphabetical-order/113527 "2024-04-26T12:39:55Z")

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I am trying to plot some measurement data using AoG. I am also pretty new to this, so I might be missing something obvious. When I try to plot data that has string entries as an X-Axis, the values get sorted by alphabet…

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## [Getting ForwardDiff jacobian! to execute with zero allocations](https://discourse.julialang.org/t/getting-forwarddiff-jacobian-to-execute-with-zero-allocations/72503)

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**Author:** [@Anthony](https://discourse.julialang.org/u/Anthony)\
**Replies:** 9\
**Last updated:** [April 26, 2024, 12:35pm UTC](https://discourse.julialang.org/t/getting-forwarddiff-jacobian-to-execute-with-zero-allocations/72503 "2024-04-26T12:35:35Z")

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I’ve been trying (so far unsuccessfully) to figure out how to execute ForwardDiff’s jacobian! function such that it will not perform additional allocations once compiled. However, I’ve been unable to figure out how to ac…

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## [Function definitions with where T undefined](https://discourse.julialang.org/t/function-definitions-with-where-t-undefined/113529)

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**Author:** [@LucasMontoya4](https://discourse.julialang.org/u/LucasMontoya4)\
**Replies:** 4\
**Last updated:** [April 26, 2024, 12:27pm UTC](https://discourse.julialang.org/t/function-definitions-with-where-t-undefined/113529 "2024-04-26T12:27:00Z")

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Hi there, after looking at pieces of code around the internet, I have occasionally seen codes where functions are defined with function foo(x, v::T) where T, or something like that. I don’t understand the point of this w…

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## [Why is rust compilation faster than Julia pre-compilation?](https://discourse.julialang.org/t/why-is-rust-compilation-faster-than-julia-pre-compilation/113257)

<div class="topic-metadata">

**Author:** [@MilesCranmer](https://discourse.julialang.org/u/MilesCranmer)\
**Replies:** 37\
**Last updated:** [April 26, 2024, 11:23am UTC](https://discourse.julialang.org/t/why-is-rust-compilation-faster-than-julia-pre-compilation/113257 "2024-04-26T11:23:32Z")

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I’ve been learning Rust a bit for tinkering with CLI tools (if curious… GitHub - MilesCranmer/rip2: A safe and ergonomic alternative to rm). One thing I noticed is that the compilation time is super fast – even faster t…

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## [Least squares with SciML NonlinearSolve.jl - how to?](https://discourse.julialang.org/t/least-squares-with-sciml-nonlinearsolve-jl-how-to/113074)

<div class="topic-metadata">

**Author:** [@Eben60](https://discourse.julialang.org/u/Eben60)\
**Replies:** 13\
**Last updated:** [April 18, 2024, 9:18pm UTC](https://discourse.julialang.org/t/least-squares-with-sciml-nonlinearsolve-jl-how-to/113074 "2024-04-18T21:18:28Z")

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Trying to get how to use it - reading Documentation unfortunately doesn’t help. The use case - a model described by a formula, and a vector of (t, y) value pairs representing e.g. experimental data. Like the example pro…

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## [Weighted PCA with MultivariateStats.jl](https://discourse.julialang.org/t/weighted-pca-with-multivariatestats-jl/113525)

<div class="topic-metadata">

**Author:** [@njacki](https://discourse.julialang.org/u/njacki)\
**Replies:** 0\
**Last updated:** [April 26, 2024, 9:26am UTC](https://discourse.julialang.org/t/weighted-pca-with-multivariatestats-jl/113525 "2024-04-26T09:26:54Z")

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Hi, I want to perfrom PCA on my dataset and assign possible different weights to my variables. According to Jolliffe (2002), this can be easily done when the weighting matrix can be factorized, i.e., W\_{ij} = \\omega\_i …

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## [Prometheus.jl release announcement](https://discourse.julialang.org/t/prometheus-jl-release-announcement/113005)

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**Author:** [@fredrikekre](https://discourse.julialang.org/u/fredrikekre)\
**Replies:** 2\
**Last updated:** [April 26, 2024, 6:27am UTC](https://discourse.julialang.org/t/prometheus-jl-release-announcement/113005 "2024-04-26T06:27:20Z")

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I want to announce Prometheus.jl - a Prometheus client for Julia. Metrics from eu-central package servers collected with Prometheus.jl, scraped by Prometheus and visualized with Grafana. Prometheus is an open-sour…

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## [What is the “standard” way to use multi-threading with dot-calls (vectorized/broadcast)?](https://discourse.julialang.org/t/what-is-the-standard-way-to-use-multi-threading-with-dot-calls-vectorized-broadcast/113473)

<div class="topic-metadata">

**Author:** [@lmtzx9h4qqnt](https://discourse.julialang.org/u/lmtzx9h4qqnt)\
**Replies:** 5\
**Last updated:** [April 26, 2024, 4:47am UTC](https://discourse.julialang.org/t/what-is-the-standard-way-to-use-multi-threading-with-dot-calls-vectorized-broadcast/113473 "2024-04-26T04:47:10Z")

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All the discussions I’ve found on this topic are years old: “Multithreaded broadcast?” thread use multiple threads in vectorized operations · Issue #1802 · JuliaLang/julia · GitHub multi-threaded (@threads) dotcall/bro…

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