# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1578

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

**Page:** 1579

---

## [Multithreading unstable with JuMP](https://discourse.julialang.org/t/multithreading-unstable-with-jump/49494)

<div class="topic-metadata">

**Author:** [@JohnZ](https://discourse.julialang.org/u/JohnZ)\
**Replies:** 15\
**Last updated:** [November 9, 2020, 6:18pm UTC](https://discourse.julialang.org/t/multithreading-unstable-with-jump/49494 "2020-11-09T18:18:53Z")

</div>

Hi, I am trying to use multithreading to make a loop parallel. That loop makes a call to a function to build the model and then optimise it. So individual iterations are independent, except that results are stored in arr…

---

## [How to remove quotes folowing variable interpolation in Run() command?](https://discourse.julialang.org/t/how-to-remove-quotes-folowing-variable-interpolation-in-run-command/49849)

<div class="topic-metadata">

**Author:** [@Fred](https://discourse.julialang.org/u/Fred)\
**Replies:** 4\
**Last updated:** [November 9, 2020, 5:19pm UTC](https://discourse.julialang.org/t/how-to-remove-quotes-folowing-variable-interpolation-in-run-command/49849 "2020-11-09T17:19:12Z")

</div>

Hi, I try to use Julia to start and existing R software. But I have problems because I dont know how to remove extra quotes added by variable interpolation. Thanks ! See example here (it is a toy example, I have a muc…

---

## [Flux multiple cores](https://discourse.julialang.org/t/flux-multiple-cores/49855)

<div class="topic-metadata">

**Author:** [@compleat](https://discourse.julialang.org/u/compleat)\
**Replies:** 0\
**Last updated:** [November 9, 2020, 5:05pm UTC](https://discourse.julialang.org/t/flux-multiple-cores/49855 "2020-11-09T17:05:52Z")

</div>

Hi All, Apologies for this very basic question, but most of the threads on this are old, and this topic (and related capability) seems to be evolving. I have been running Flux on an 8-core machine, but I only just real…

---

## [Very basic GLM help](https://discourse.julialang.org/t/very-basic-glm-help/49832)

<div class="topic-metadata">

**Author:** [@HelgavonLichtenstein](https://discourse.julialang.org/u/HelgavonLichtenstein)\
**Replies:** 6\
**Last updated:** [November 9, 2020, 5:13pm UTC](https://discourse.julialang.org/t/very-basic-glm-help/49832 "2020-11-09T17:13:25Z")

</div>

Hello, I have been trying to learn how to use GLM.jl but I really don’t understand it. My goal is to show a linear model on a plot. I know how to create the base plot, but not the linear model or how to plot that onto th…

---

## [Can't add packages](https://discourse.julialang.org/t/cant-add-packages/49816)

<div class="topic-metadata">

**Author:** [@xFrenchy](https://discourse.julialang.org/u/xFrenchy)\
**Replies:** 5\
**Last updated:** [November 9, 2020, 4:26pm UTC](https://discourse.julialang.org/t/cant-add-packages/49816 "2020-11-09T16:26:45Z")

</div>

Hey everyone, it appears that I cannot add packages anymore due to the path being wrong. In the past I’ve been able to add packages without any issue and I was messing around with creating a package and now it appears to…

---

## [Conceptual problem with user recipes: draw a sphere before drawing the data](https://discourse.julialang.org/t/conceptual-problem-with-user-recipes-draw-a-sphere-before-drawing-the-data/49385)

<div class="topic-metadata">

**Author:** [@kellertuer](https://discourse.julialang.org/u/kellertuer)\
**Replies:** 5\
**Last updated:** [November 9, 2020, 3:00pm UTC](https://discourse.julialang.org/t/conceptual-problem-with-user-recipes-draw-a-sphere-before-drawing-the-data/49385 "2020-11-09T15:00:18Z")

</div>

I am trying to do a user recipe from RecipesBase.jl but I seem to not get the idea how Recipes work I fear. Context. I would like to do something that I thought was quite easy. Given the M=Sphere(2) from Manifolds.jl a…

---

## [JuliaPro Error - SystemError: unable to read directory](https://discourse.julialang.org/t/juliapro-error-systemerror-unable-to-read-directory/49844)

<div class="topic-metadata">

**Author:** [@orthoeng](https://discourse.julialang.org/u/orthoeng)\
**Replies:** 0\
**Last updated:** [November 9, 2020, 1:35pm UTC](https://discourse.julialang.org/t/juliapro-error-systemerror-unable-to-read-directory/49844 "2020-11-09T13:35:43Z")

</div>

I just get this Error with JuliaPro - JupyterNote works fine - MacBook Pro 2019 \[c52e3926\] Atom v0.12.23 ⚲ \[336ed68f\] CSV v0.7.7 \[a93c6f00\] DataFrames v0.21.8 \[c27321d9\] Glob v1.3.0 \[7073ff75\] IJulia v1.22.0 \[a933…

---

## [Cant add plots](https://discourse.julialang.org/t/cant-add-plots/49843)

<div class="topic-metadata">

**Author:** [@Stropy28](https://discourse.julialang.org/u/Stropy28)\
**Replies:** 3\
**Last updated:** [November 9, 2020, 2:56pm UTC](https://discourse.julialang.org/t/cant-add-plots/49843 "2020-11-09T14:56:51Z")

</div>

Can anyone help me with this problem?

---

## [Add UMAP to julia](https://discourse.julialang.org/t/add-umap-to-julia/49813)

<div class="topic-metadata">

**Author:** [@bhavinmoriya](https://discourse.julialang.org/u/bhavinmoriya)\
**Replies:** 4\
**Last updated:** [November 9, 2020, 2:44pm UTC](https://discourse.julialang.org/t/add-umap-to-julia/49813 "2020-11-09T14:44:52Z")

</div>

Hi, I was trying to add the package UMAP, while doing so, the following message showed up, RROR: Unsatisfiable requirements detected for package Distances \[b4f34e82\]: Distances \[b4f34e82\] log: ├─possible versions are…

---

## [How to add different meshes in JuAFEM?](https://discourse.julialang.org/t/how-to-add-different-meshes-in-juafem/49769)

<div class="topic-metadata">

**Author:** [@Hrishikesh\_Das](https://discourse.julialang.org/u/Hrishikesh_Das)\
**Replies:** 7\
**Last updated:** [November 9, 2020, 2:18pm UTC](https://discourse.julialang.org/t/how-to-add-different-meshes-in-juafem/49769 "2020-11-09T14:18:34Z")

</div>

I am using the package JuAFEM. I want to join three different meshes and make it into one. Below is the picture attached. Plz help.

---

## [DifferentialEquations: mysterious problem](https://discourse.julialang.org/t/differentialequations-mysterious-problem/49836)

<div class="topic-metadata">

**Author:** [@BLI](https://discourse.julialang.org/u/BLI)\
**Replies:** 2\
**Last updated:** [November 9, 2020, 1:24pm UTC](https://discourse.julialang.org/t/differentialequations-mysterious-problem/49836 "2020-11-09T13:24:45Z")

</div>

I’m simulating a model with 8 states using DifferentialEquations and get the expected result: \[Red line is simulation; scatter plot is experimental values.\] Next, I double the model by simulating two identical model…

---

## [Array variable - matrix multplication in JuMP](https://discourse.julialang.org/t/array-variable-matrix-multplication-in-jump/49801)

<div class="topic-metadata">

**Author:** [@shashankchahar](https://discourse.julialang.org/u/shashankchahar)\
**Replies:** 2\
**Last updated:** [November 9, 2020, 1:12pm UTC](https://discourse.julialang.org/t/array-variable-matrix-multplication-in-jump/49801 "2020-11-09T13:12:30Z")

</div>

Hello, I am new to Julia and trying to convert one of the tasks that I used to do in Excel into Julia. I need to find a matrix X. Matrix X represents discrete Markov model transition probabilities with the final column …

---

## [Crashed Julia with \<](https://discourse.julialang.org/t/crashed-julia-with/49831)

<div class="topic-metadata">

**Author:** [@stefkuypers](https://discourse.julialang.org/u/stefkuypers)\
**Replies:** 2\
**Last updated:** [November 9, 2020, 11:57am UTC](https://discourse.julialang.org/t/crashed-julia-with/49831 "2020-11-09T11:57:09Z")

</div>

Hi, I have defined the following two types: struct Percentage \<: Real value::Float64 Percentage(x) = x \< 0 ? new(0) : x \> 1 ? new(1) : new(round(x, digits = 6)) end Base.show(io::IO, x::Percentage) = print(io,…

---

## [Trying to initialise a struct with a sorted Vector](https://discourse.julialang.org/t/trying-to-initialise-a-struct-with-a-sorted-vector/49830)

<div class="topic-metadata">

**Author:** [@stefkuypers](https://discourse.julialang.org/u/stefkuypers)\
**Replies:** 3\
**Last updated:** [November 9, 2020, 11:36am UTC](https://discourse.julialang.org/t/trying-to-initialise-a-struct-with-a-sorted-vector/49830 "2020-11-09T11:36:01Z")

</div>

Hi, I have a struct with 2 Vector fields holding Tuples. When creating a new object I want the Vectors to be sorted but for some reason it’s not working. abstract type Lifecycle end struct Restorable \<: Lifecycle …

---

## [\[ANN\] PrettyTables.jl - Print formatted tables in Julia](https://discourse.julialang.org/t/ann-prettytables-jl-print-formatted-tables-in-julia/19550)

<div class="topic-metadata">

**Author:** [@Ronis\_BR](https://discourse.julialang.org/u/Ronis_BR)\
**Replies:** 84\
**Last updated:** [November 9, 2020, 11:13am UTC](https://discourse.julialang.org/t/ann-prettytables-jl-print-formatted-tables-in-julia/19550 "2020-11-09T11:13:21Z")

</div>

Hi guys! I want to announce a new package that I just submitted for registration. It is called PrettyTables.jl. The idea is to provide functionality to print data in tables in many formats. Currently, it supports only t…

---

## [Simulating a stopping time in SDE without using a fixed time span?](https://discourse.julialang.org/t/simulating-a-stopping-time-in-sde-without-using-a-fixed-time-span/45608)

<div class="topic-metadata">

**Author:** [@tzxiong](https://discourse.julialang.org/u/tzxiong)\
**Replies:** 6\
**Last updated:** [November 9, 2020, 9:27am UTC](https://discourse.julialang.org/t/simulating-a-stopping-time-in-sde-without-using-a-fixed-time-span/45608 "2020-11-09T09:27:44Z")

</div>

Hi everyone, I am trying to simulate a stochastic process on \[0,1\] that will hit the boundary with probability 1 in a finite amount of time. The package I am using is the SDE solver in DifferentialEquation.jl. However, …

---

## [How do I reset a variable value in a loop?](https://discourse.julialang.org/t/how-do-i-reset-a-variable-value-in-a-loop/49821)

<div class="topic-metadata">

**Author:** [@carlos](https://discourse.julialang.org/u/carlos)\
**Replies:** 2\
**Last updated:** [November 9, 2020, 9:19am UTC](https://discourse.julialang.org/t/how-do-i-reset-a-variable-value-in-a-loop/49821 "2020-11-09T09:19:47Z")

</div>

Let’s say I have a model like this: using JuMP using CPLEX model = Model(CPLEX.Optimizer) for k = 1:3 @variables(model, begin sigma x\[1:3\]\>=0 end) @constraints(model,begin sigma == sum(x\[i\]…

---

## [Add sum term to ODE in DifferentialEquations](https://discourse.julialang.org/t/add-sum-term-to-ode-in-differentialequations/49463)

<div class="topic-metadata">

**Author:** [@Luigi\_Marongiu](https://discourse.julialang.org/u/Luigi_Marongiu)\
**Replies:** 4\
**Last updated:** [November 9, 2020, 9:13am UTC](https://discourse.julialang.org/t/add-sum-term-to-ode-in-differentialequations/49463 "2020-11-09T09:13:10Z")

</div>

Hello, I wrote some ODEs in Julia with DifferentialEquations. Now I have to translate the following into Julia: The ODEs I have written are: function ode!(du, u, p, t) μ, ϕ, ω, β, τ = p #= with: a = μ …

---

## [ERROR: LoadError: Unable to import Arpack\_jll on Julia versions older than 1.3!](https://discourse.julialang.org/t/error-loaderror-unable-to-import-arpack-jll-on-julia-versions-older-than-1-3/34603)

<div class="topic-metadata">

**Author:** [@ablaom](https://discourse.julialang.org/u/ablaom)\
**Replies:** 5\
**Last updated:** [November 9, 2020, 8:55am UTC](https://discourse.julialang.org/t/error-loaderror-unable-to-import-arpack-jll-on-julia-versions-older-than-1-3/34603 "2020-11-09T08:55:30Z")

</div>

Anyone have any ideas about this? julia\> using MLJBase \[ Info: Precompiling MLJBase \[a7f614a8-145f-11e9-1d2a-a57a1082229d\] ERROR: LoadError: Unable to import Arpack\_jll on Julia versions older than 1.3! Stacktrace: \[1\]…

---

## [Converting from 24-bit image as byte array to RGB](https://discourse.julialang.org/t/converting-from-24-bit-image-as-byte-array-to-rgb/49806)

<div class="topic-metadata">

**Author:** [@Eben60](https://discourse.julialang.org/u/Eben60)\
**Replies:** 3\
**Last updated:** [November 9, 2020, 8:45am UTC](https://discourse.julialang.org/t/converting-from-24-bit-image-as-byte-array-to-rgb/49806 "2020-11-09T08:45:17Z")

</div>

I am working on Data-exchange Julia-LabView - #13 by Eben60 . Now I’m trying to send image data to Julia. I get image now as 3xMxN array of UInt8. How to convert it to RGB? The following works, but it must be possible to…

---

## [Gnuplot.jl opens up plot pane as well as an external window](https://discourse.julialang.org/t/gnuplot-jl-opens-up-plot-pane-as-well-as-an-external-window/49822)

<div class="topic-metadata">

**Author:** [@affans](https://discourse.julialang.org/u/affans)\
**Replies:** 1\
**Last updated:** [November 9, 2020, 4:36am UTC](https://discourse.julialang.org/t/gnuplot-jl-opens-up-plot-pane-as-well-as-an-external-window/49822 "2020-11-09T04:36:34Z")

</div>

Plotting a figure using Gnuplot.jl inside VSCode will display an external window + the plot pane (however, the plot pane is empty). I am using WSL 2, so using the Remote - WSL extension on VSCode and also running an X-S…

---

## [Clone Julia version from user's \`~/.Julia\`](https://discourse.julialang.org/t/clone-julia-version-from-users-julia/49820)

<div class="topic-metadata">

**Author:** [@lobshi](https://discourse.julialang.org/u/lobshi)\
**Replies:** 0\
**Last updated:** [November 9, 2020, 3:40am UTC](https://discourse.julialang.org/t/clone-julia-version-from-users-julia/49820 "2020-11-09T03:40:51Z")

</div>

Hi, I updated my Julia by downloading the newest version from official website. Now I get stuck when I try to update the Julia in Anaconda environment. Is there any easy way to update Julia in Conda, no matter by clonin…

---

## [Pronounciation guide?](https://discourse.julialang.org/t/pronounciation-guide/49556)

<div class="topic-metadata">

**Author:** [@claforte](https://discourse.julialang.org/u/claforte)\
**Replies:** 12\
**Last updated:** [November 9, 2020, 2:41am UTC](https://discourse.julialang.org/t/pronounciation-guide/49556 "2020-11-09T02:41:02Z")

</div>

Hi, I love Julia but I have a hard type guessing how some of the functions/operators are called/pronounced. For instance, how do people pronounce: → =\> …? Single-arrow, double-arrow? It would be great if the documen…

---

## [CUDA/Flux installation error ubuntu 20, cuda toolkit 11, julia 1.5.2](https://discourse.julialang.org/t/cuda-flux-installation-error-ubuntu-20-cuda-toolkit-11-julia-1-5-2/49812)

<div class="topic-metadata">

**Author:** [@Neurovium](https://discourse.julialang.org/u/Neurovium)\
**Replies:** 4\
**Last updated:** [November 9, 2020, 1:54am UTC](https://discourse.julialang.org/t/cuda-flux-installation-error-ubuntu-20-cuda-toolkit-11-julia-1-5-2/49812 "2020-11-09T01:54:35Z")

</div>

Hi I have updated ubuntu t0 20.04, julia to 1.5.2 and cuda toolkit to 111, and I have trouble with both CUDA and Flux. They both get installed but do not pass test or compile. I removed one tried the other, changed the…

---

## [\[ANN\] Metadata.jl](https://discourse.julialang.org/t/ann-metadata-jl/49662)

<div class="topic-metadata">

**Author:** [@Zach\_Christensen](https://discourse.julialang.org/u/Zach_Christensen)\
**Replies:** 4\
**Last updated:** [November 8, 2020, 10:59pm UTC](https://discourse.julialang.org/t/ann-metadata-jl/49662 "2020-11-08T22:59:08Z")

</div>

Hi everyone, I’d like to announce the Metadata.jl. It attempts to provide a generic and common interface for attaching and extracting metadata. This is mostly done by assuming that metadata has Symbol keys. Metadata can…

---

## [Unable to expand derivatives in modelingtoolkit](https://discourse.julialang.org/t/unable-to-expand-derivatives-in-modelingtoolkit/49803)

<div class="topic-metadata">

**Author:** [@brett\_knoss](https://discourse.julialang.org/u/brett_knoss)\
**Replies:** 2\
**Last updated:** [November 8, 2020, 10:03pm UTC](https://discourse.julialang.org/t/unable-to-expand-derivatives-in-modelingtoolkit/49803 "2020-11-08T22:03:03Z")

</div>

using ModelingToolkit @variables x y Δy u μ # these are symbols, they are used in symbolic computing @derivatives δx'~x δy'~y δu'~u δμ'~μ # these are derivatives, they are assigned with macros expand\_derivatives(δu(sq…

---

## [What depends on AbstractArray Iteration Order?](https://discourse.julialang.org/t/what-depends-on-abstractarray-iteration-order/49704)

<div class="topic-metadata">

**Author:** [@Luapulu](https://discourse.julialang.org/u/Luapulu)\
**Replies:** 16\
**Last updated:** [November 8, 2020, 9:55pm UTC](https://discourse.julialang.org/t/what-depends-on-abstractarray-iteration-order/49704 "2020-11-08T21:55:37Z")

</div>

Should every AbstractArray be iterated over in cloumn-major order only? In other words, what relies on iterate preceding in a set order for AbstractArrays? To clarify, I mean iteration order in a very general sense. Cou…

---

## [Reading mps file with MathProgBase](https://discourse.julialang.org/t/reading-mps-file-with-mathprogbase/49776)

<div class="topic-metadata">

**Author:** [@Pierre-Louis\_Poirion](https://discourse.julialang.org/u/Pierre-Louis_Poirion)\
**Replies:** 3\
**Last updated:** [November 8, 2020, 8:14pm UTC](https://discourse.julialang.org/t/reading-mps-file-with-mathprogbase/49776 "2020-11-08T20:14:01Z")

</div>

Hi, I am trying to read a mps file using the following code: using JuMP using MathProgBase using Gurobi … function readLP(s) m\_internal = MathProgBase.LinearQuadraticModel(GurobiSolver()) MathProgBase.loadproblem…

---

## [Array comparison](https://discourse.julialang.org/t/array-comparison/49795)

<div class="topic-metadata">

**Author:** [@goosst](https://discourse.julialang.org/u/goosst)\
**Replies:** 4\
**Last updated:** [November 8, 2020, 7:50pm UTC](https://discourse.julialang.org/t/array-comparison/49795 "2020-11-08T19:50:26Z")

</div>

This seems like a very newby question, since I’m trying to do something very simple. I want to find the array elements between two values. I can make it work with my third attempt in the code, but it feels like there is…

---

## [Resize arrays in mutable structs](https://discourse.julialang.org/t/resize-arrays-in-mutable-structs/49701)

<div class="topic-metadata">

**Author:** [@robertdj](https://discourse.julialang.org/u/robertdj)\
**Replies:** 6\
**Last updated:** [November 8, 2020, 7:27pm UTC](https://discourse.julialang.org/t/resize-arrays-in-mutable-structs/49701 "2020-11-08T19:27:36Z")

</div>

In my Deldir package I use ccall on a code with 17 arguments that are all vectors. I have collected those in a mutable struct. When executing the ccall the content of the vectors in the struct are replaced. If the Fortr…

[Previous page](https://discourse.julialang.org/latest.md?page=1577)

[Next page](https://discourse.julialang.org/latest.md?page=1579)