# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1412

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

**Page:** 1413

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## [How often do you use the |\> operator?](https://discourse.julialang.org/t/how-often-do-you-use-the-operator/56189)

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**Author:** [@anon74562486](https://discourse.julialang.org/u/anon74562486)\
**Replies:** 56\
**Last updated:** [April 26, 2021, 1:16am UTC](https://discourse.julialang.org/t/how-often-do-you-use-the-operator/56189 "2021-04-26T01:16:33Z")

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I really like pipe operator (|\>) but if I see the source code of libraries I see that it is often used like this: a = function\_2(function\_1(input\_data)) |\> gpu rather than this: a = input\_data |\> function\_1 |\> …

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## [Issue with LLVM.jl with non-ascii user names on Windows](https://discourse.julialang.org/t/issue-with-llvm-jl-with-non-ascii-user-names-on-windows/59932)

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**Author:** [@angeloaliano1](https://discourse.julialang.org/u/angeloaliano1)\
**Replies:** 26\
**Last updated:** [April 25, 2021, 11:35pm UTC](https://discourse.julialang.org/t/issue-with-llvm-jl-with-non-ascii-user-names-on-windows/59932 "2021-04-25T23:35:58Z")

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Dear all, I have Installed the package DifferentialEquations. However, when I run using DifferentialEquations an enormous problem apperars: see below. Failed to precompile DifferentialEquations \[0c46a032-eb83-5123-ab…

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## [\[DifferentialEquations.jl\] Can't brodcast time gradients into dualcache](https://discourse.julialang.org/t/differentialequations-jl-cant-brodcast-time-gradients-into-dualcache/60007)

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**Author:** [@MatFi](https://discourse.julialang.org/u/MatFi)\
**Replies:** 4\
**Last updated:** [April 25, 2021, 10:05pm UTC](https://discourse.julialang.org/t/differentialequations-jl-cant-brodcast-time-gradients-into-dualcache/60007 "2021-04-25T22:05:38Z")

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I need to cache some data during the evaluation of an ODE. However the time gradients make it a bit difficult to me and cuse a MethodError. MWE using DiffEqBase, OrdinaryDiffEq struct rb{T} B::T end rb(n::Integer)…

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## [Eigenvectors of very large (non-sparse) symmetric matrices?](https://discourse.julialang.org/t/eigenvectors-of-very-large-non-sparse-symmetric-matrices/59885)

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**Author:** [@JedPhillips](https://discourse.julialang.org/u/JedPhillips)\
**Replies:** 11\
**Last updated:** [April 25, 2021, 7:57pm UTC](https://discourse.julialang.org/t/eigenvectors-of-very-large-non-sparse-symmetric-matrices/59885 "2021-04-25T19:57:29Z")

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I’m trying to get the first 50 dominant eigenvectors of a huge symmetric matrix, of dimension 65000 x 65000. I’m doing this on a computer cluster, so there’s no RAM limitation. But it still takes forever. In fact I don’t…

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## [\`x==y\` is true but \`π^x == π^y\` is false](https://discourse.julialang.org/t/x-y-is-true-but-x-y-is-false/59976)

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**Author:** [@HJW019](https://discourse.julialang.org/u/HJW019)\
**Replies:** 8\
**Last updated:** [April 25, 2021, 5:58pm UTC](https://discourse.julialang.org/t/x-y-is-true-but-x-y-is-false/59976 "2021-04-25T17:58:25Z")

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A simple question for you CS experts: function foo() x::Float32 = 0.5 y::Float64 = 0.5 return x==y, π^x == π^y end julia\> foo() (true, false) Why x==y is true given the different numeric types? And if x==y …

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## [How to draw 2D text on top of a 3D figure with Makie](https://discourse.julialang.org/t/how-to-draw-2d-text-on-top-of-a-3d-figure-with-makie/59983)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 4\
**Last updated:** [April 25, 2021, 4:43pm UTC](https://discourse.julialang.org/t/how-to-draw-2d-text-on-top-of-a-3d-figure-with-makie/59983 "2021-04-25T16:43:43Z")

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I have the following code: using GeometryBasics, GLMakie const SCALE = 1.2 const SEGMENTS = 7 # number of tether segments function create\_coordinate\_system(scene, points = 10, length = 10) # cre…

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## [Current state of telemetry and side question about anaconda security concerns](https://discourse.julialang.org/t/current-state-of-telemetry-and-side-question-about-anaconda-security-concerns/59943)

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**Author:** [@anon69491625](https://discourse.julialang.org/u/anon69491625)\
**Replies:** 6\
**Last updated:** [April 25, 2021, 3:14pm UTC](https://discourse.julialang.org/t/current-state-of-telemetry-and-side-question-about-anaconda-security-concerns/59943 "2021-04-25T15:14:44Z")

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Hi all, I am going to reinstall Julia from scratch on Linux mint and at least one of the books I have read about Julia suggest that I do so using anaconda. I am coming from Python so the only things I ever installed wer…

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## [Why is this Plots.jl contour plot blank?](https://discourse.julialang.org/t/why-is-this-plots-jl-contour-plot-blank/59990)

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**Author:** [@cadojo](https://discourse.julialang.org/u/cadojo)\
**Replies:** 1\
**Last updated:** [April 25, 2021, 2:46pm UTC](https://discourse.julialang.org/t/why-is-this-plots-jl-contour-plot-blank/59990 "2021-04-25T14:46:20Z")

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I’m trying to produce a “pork chop” plot for an aerospace engineering assignment. I’m using Plots.jl, and the GR backend. I want to plot a contour plot, with \\Delta v as the “z” axis. For some reason, I can plot the dat…

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## [Discretized HMC](https://discourse.julialang.org/t/discretized-hmc/59964)

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**Author:** [@ParadaCarleton](https://discourse.julialang.org/u/ParadaCarleton)\
**Replies:** 1\
**Last updated:** [April 25, 2021, 2:25pm UTC](https://discourse.julialang.org/t/discretized-hmc/59964 "2021-04-25T14:25:48Z")

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Is there any interest in implementing generalizations of HMC to discrete spaces for Turing.jl? Examples: https://www.tandfonline.com/doi/full/10.1080/01621459.2019.1585255?casa\_token=XuidyAblCZQAAAAA:FrOpfFdJWbBrG1R0-ZN…

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## [CUDA.jl tex2DLayered support?](https://discourse.julialang.org/t/cuda-jl-tex2dlayered-support/59625)

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**Author:** [@jpdoane](https://discourse.julialang.org/u/jpdoane)\
**Replies:** 2\
**Last updated:** [April 25, 2021, 1:25pm UTC](https://discourse.julialang.org/t/cuda-jl-tex2dlayered-support/59625 "2021-04-25T13:25:16Z")

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Is there a plan to integrate Layered Textures support into CUDA.jl? I am currently using a 3D texture for my application, but I suspect I am getting sub-optimal performance since my data structure really is a set of 2D …

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## [Arpack in Ubuntu](https://discourse.julialang.org/t/arpack-in-ubuntu/59795)

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**Author:** [@MARIANO\_SIMON\_ARNAIZ](https://discourse.julialang.org/u/MARIANO_SIMON_ARNAIZ)\
**Replies:** 12\
**Last updated:** [April 25, 2021, 1:22pm UTC](https://discourse.julialang.org/t/arpack-in-ubuntu/59795 "2021-04-25T13:22:04Z")

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Hi everyone… I wonder if you can help me with the usage of Arpack in Ubuntu… it works great in Mac (wrapping the arpack I installed with homebrew). But I have installed it in Ubuntu and won’t work I get this when I try …

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## [Arpack is too slow?](https://discourse.julialang.org/t/arpack-is-too-slow/59945)

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**Author:** [@marianoarnaiz](https://discourse.julialang.org/u/marianoarnaiz)\
**Replies:** 6\
**Last updated:** [April 25, 2021, 1:21pm UTC](https://discourse.julialang.org/t/arpack-is-too-slow/59945 "2021-04-25T13:21:26Z")

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Hi everyone. I have a code for computing Surface Wave dispersion velocity (seismology) and it takes about 6 s to run. Of those, 4.5 s are spent on this for loop that calls Arpack to solve the generalised eigenvalue and …

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## [Embedding Makie plots in Stipple](https://discourse.julialang.org/t/embedding-makie-plots-in-stipple/59987)

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**Author:** [@kobied](https://discourse.julialang.org/u/kobied)\
**Replies:** 0\
**Last updated:** [April 25, 2021, 1:13pm UTC](https://discourse.julialang.org/t/embedding-makie-plots-in-stipple/59987 "2021-04-25T13:13:39Z")

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hi, I’m working on some GUI which, as for now, is based on Stipple.jl and Makie.jl. At the Makie side, I have a window with a Figure which has 2 Axis layout, for each axis I created some mouse and keyboard interactive f…

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## [MakieGL fails after update](https://discourse.julialang.org/t/makiegl-fails-after-update/59978)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 8\
**Last updated:** [April 25, 2021, 10:20am UTC](https://discourse.julialang.org/t/makiegl-fails-after-update/59978 "2021-04-25T10:20:23Z")

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I am using MakieGL on Ubuntu 18.04. It used to work fine, but after an update it doesn’t work any more. I updated: Julia to 1.6.1 MakieGL to latest stable version and Ubuntu updated the nvidea graphics drivers. The …

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## [Why is Optim.optimize() throwing an exception if I provide initial\_invH?](https://discourse.julialang.org/t/why-is-optim-optimize-throwing-an-exception-if-i-provide-initial-invh/59872)

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**Author:** [@marcus-waldman](https://discourse.julialang.org/u/marcus-waldman)\
**Replies:** 4\
**Last updated:** [April 25, 2021, 10:06am UTC](https://discourse.julialang.org/t/why-is-optim-optimize-throwing-an-exception-if-i-provide-initial-invh/59872 "2021-04-25T10:06:59Z")

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I’m trying to implement the EM algorithm to estimate parameters in a large model The EM algorithm requires a lot of back and forth updating some parameters of interest and then optimizing an objective function based on t…

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## [Debugger enters a second level of the same function](https://discourse.julialang.org/t/debugger-enters-a-second-level-of-the-same-function/59979)

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**Author:** [@conditionality](https://discourse.julialang.org/u/conditionality)\
**Replies:** 1\
**Last updated:** [April 25, 2021, 9:28am UTC](https://discourse.julialang.org/t/debugger-enters-a-second-level-of-the-same-function/59979 "2021-04-25T09:28:12Z")

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Hi, I’m curious about why the debugger behaves as it does in the following case. I’m debugging the file https://github.com/FluxML/model-zoo/blob/master/vision/vae\_mnist/vae\_mnist.jl and I’m putting a breakpoint at row 9…

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## [Error when importing package from Github](https://discourse.julialang.org/t/error-when-importing-package-from-github/59952)

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**Author:** [@Wei1](https://discourse.julialang.org/u/Wei1)\
**Replies:** 2\
**Last updated:** [April 25, 2021, 8:43am UTC](https://discourse.julialang.org/t/error-when-importing-package-from-github/59952 "2021-04-25T08:43:06Z")

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When I was trying to import a package from Github, it returns errors like this - does anyone know how to fix this?

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## [Problems with stiff solvers for MTK model](https://discourse.julialang.org/t/problems-with-stiff-solvers-for-mtk-model/59658)

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**Author:** [@ohmsweetohm1](https://discourse.julialang.org/u/ohmsweetohm1)\
**Replies:** 4\
**Last updated:** [April 25, 2021, 8:14am UTC](https://discourse.julialang.org/t/problems-with-stiff-solvers-for-mtk-model/59658 "2021-04-25T08:14:57Z")

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I have a MTK model (copy paste from docs): using ModelingToolkit, Plots, DifferentialEquations @parameters t function Pin(;name) @variables v(t) i(t) ODESystem(Equation\[\], t, \[v, i\], \[\], name=name, defaults=\[v…

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## [How to sample multiple self defined random variable](https://discourse.julialang.org/t/how-to-sample-multiple-self-defined-random-variable/59847)

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**Author:** [@Wei\_Yang](https://discourse.julialang.org/u/Wei_Yang)\
**Replies:** 4\
**Last updated:** [April 25, 2021, 7:50am UTC](https://discourse.julialang.org/t/how-to-sample-multiple-self-defined-random-variable/59847 "2021-04-25T07:50:47Z")

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I have defined the following Distribution, using Distributions struct ComplexNormal \<:ContinuousUnivariateDistribution μ::ComplexF64 σ::Float64 function ComplexNormal(μ=0,σ=1) new(μ,σ) end end function B…

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## [Error building \`Gurobi\`](https://discourse.julialang.org/t/error-building-gurobi/59852)

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**Author:** [@zlq178](https://discourse.julialang.org/u/zlq178)\
**Replies:** 6\
**Last updated:** [April 25, 2021, 7:38am UTC](https://discourse.julialang.org/t/error-building-gurobi/59852 "2021-04-25T07:38:00Z")

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I have installed Gurobi.jl(v"0.8.1"), When I build it, some wrong happened. Julia version:JuliaPro 1.5.1-1. What should I do next? Thank you for your help. julia\>ENV\["GUROBI\_HOME"\] = "C:\\\\gurobi911\\\\win64" julia\>import…

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## [I cannot install Plots in Julia 1.6.1](https://discourse.julialang.org/t/i-cannot-install-plots-in-julia-1-6-1/59971)

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**Author:** [@HerAdri](https://discourse.julialang.org/u/HerAdri)\
**Replies:** 1\
**Last updated:** [April 25, 2021, 7:37am UTC](https://discourse.julialang.org/t/i-cannot-install-plots-in-julia-1-6-1/59971 "2021-04-25T07:37:25Z")

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\_ \_ \_ \_(\_)\_ | Documentation: https://docs.julialang.org (\_) | (\_) (\_) | \_ \_ \_| |\_ \_\_ \_ | Type "?" for help, "\]?" for Pkg help. | | | | | | |/ \_\` | | | | |\_| | | | (\_| |…

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## [Compatibility with previous versions of Julia: how much makes sense for a new package?](https://discourse.julialang.org/t/compatibility-with-previous-versions-of-julia-how-much-makes-sense-for-a-new-package/59920)

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**Author:** [@andreasvarga](https://discourse.julialang.org/u/andreasvarga)\
**Replies:** 4\
**Last updated:** [April 25, 2021, 7:29am UTC](https://discourse.julialang.org/t/compatibility-with-previous-versions-of-julia-how-much-makes-sense-for-a-new-package/59920 "2021-04-25T07:29:59Z")

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I am developing several computational packages, mainly oriented towards control system applications. Several times I was confronted with keeping compatibility with earlier versions of Julia, where I set (I don’t remember…

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## [PowerModels generation and branch result data extraction](https://discourse.julialang.org/t/powermodels-generation-and-branch-result-data-extraction/59973)

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**Author:** [@aaldik](https://discourse.julialang.org/u/aaldik)\
**Replies:** 0\
**Last updated:** [April 25, 2021, 6:06am UTC](https://discourse.julialang.org/t/powermodels-generation-and-branch-result-data-extraction/59973 "2021-04-25T06:06:57Z")

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Dears I’m working on the package PowerModels and I’m trying to extract results data for further manipulation. the problem that I have faced is regrading generation results and how to extract them in an accurate way. I h…

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## [Acausal modeling with ModelingToolkit.jl: Why does structural\_simplify not eliminate one more variable?](https://discourse.julialang.org/t/acausal-modeling-with-modelingtoolkit-jl-why-does-structural-simplify-not-eliminate-one-more-variable/59474)

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**Author:** [@frnkcg](https://discourse.julialang.org/u/frnkcg)\
**Replies:** 10\
**Last updated:** [April 25, 2021, 5:28am UTC](https://discourse.julialang.org/t/acausal-modeling-with-modelingtoolkit-jl-why-does-structural-simplify-not-eliminate-one-more-variable/59474 "2021-04-25T05:28:07Z")

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I know a little bit of Modelica so when I recently encountered ModelingToolkit.jl, I was excited to try it out. But I ran into some unexpected problems even for a very simple model. I created an acausal model of a simpl…

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## [Updating Old Julia Code - Cant get past ArgumentError: Invalid Index](https://discourse.julialang.org/t/updating-old-julia-code-cant-get-past-argumenterror-invalid-index/59894)

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**Author:** [@Kashjew](https://discourse.julialang.org/u/Kashjew)\
**Replies:** 7\
**Last updated:** [April 25, 2021, 4:33am UTC](https://discourse.julialang.org/t/updating-old-julia-code-cant-get-past-argumenterror-invalid-index/59894 "2021-04-25T04:33:48Z")

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Hello. I am new to Julia and I have been updating the code from the Picking Winner’s Paper (GitHub - zlisto/Daily-Fantasy-Baseball-Contests-in-DraftKings: This is the code for constructing a portfolio of lineups for Draf…

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## [Warning message of token](https://discourse.julialang.org/t/warning-message-of-token/59965)

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**Author:** [@angeloaliano1](https://discourse.julialang.org/u/angeloaliano1)\
**Replies:** 0\
**Last updated:** [April 25, 2021, 2:25am UTC](https://discourse.julialang.org/t/warning-message-of-token/59965 "2021-04-25T02:25:41Z")

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Dear all, My Julia are with some warning messages very noises when I need to download a package. See the figures below. Specially when I need to download the token in https://juliahub.com/auth/renew/token.toml/v2/ How…

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## [Using a posterior from a previous sample as a prior](https://discourse.julialang.org/t/using-a-posterior-from-a-previous-sample-as-a-prior/59914)

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**Author:** [@pthompson234](https://discourse.julialang.org/u/pthompson234)\
**Replies:** 2\
**Last updated:** [April 25, 2021, 2:00am UTC](https://discourse.julialang.org/t/using-a-posterior-from-a-previous-sample-as-a-prior/59914 "2021-04-25T02:00:34Z")

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Sorry if this is a question that has already been asked, or if this is the wrong place for something like this - I’ve done a bit of searching and haven’t found anything that works for the Turing package. In short, what I…

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## [Why the dimension of V1 = ℤ₂Space(0=\>3,1=\>2) is 5?](https://discourse.julialang.org/t/why-the-dimension-of-v1-space-0-3-1-2-is-5/59960)

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**Author:** [@Nellatur](https://discourse.julialang.org/u/Nellatur)\
**Replies:** 0\
**Last updated:** [April 25, 2021, 12:29am UTC](https://discourse.julialang.org/t/why-the-dimension-of-v1-space-0-3-1-2-is-5/59960 "2021-04-25T00:29:48Z")

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I am not sure if this question would belong to mathematics or more suitable for mathematics stackexchange. It comes from https://jutho.github.io/TensorKit.jl/stable/man/tutorial/#Symmetries julia\> V1 = ℤ₂Space(0=\>3,1=\>2…

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## [Issue compiling GR\_jll on hpc](https://discourse.julialang.org/t/issue-compiling-gr-jll-on-hpc/59898)

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**Author:** [@mkarikom](https://discourse.julialang.org/u/mkarikom)\
**Replies:** 5\
**Last updated:** [April 25, 2021, 12:03am UTC](https://discourse.julialang.org/t/issue-compiling-gr-jll-on-hpc/59898 "2021-04-25T00:03:35Z")

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I searched available modules on this hpc cluster and nothing like “libqt” showed up so I’m assuming this is always in the path. For some reason I still get this error: julia\> using GR\_jll \[ Info: Precompiling GR\_jll \[d…

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## [What Does \`:=\` Do?](https://discourse.julialang.org/t/what-does-do/59957)

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**Author:** [@ParadaCarleton](https://discourse.julialang.org/u/ParadaCarleton)\
**Replies:** 5\
**Last updated:** [April 24, 2021, 10:25pm UTC](https://discourse.julialang.org/t/what-does-do/59957 "2021-04-24T22:25:40Z")

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What the title says. I can’t figure it out, and the docs just provide the not at all useful description: x := y is a synonym for x = x : y Which apparently means something different from what I expected to, given the f…

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