# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1002

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

**Page:** 1003

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## [Reported stacktrace are terrible for errors :-/](https://discourse.julialang.org/t/reported-stacktrace-are-terrible-for-errors/83193)

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**Author:** [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Replies:** 2\
**Last updated:** [June 22, 2022, 3:44pm UTC](https://discourse.julialang.org/t/reported-stacktrace-are-terrible-for-errors/83193 "2022-06-22T15:44:59Z")

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I am sure this must already have been discussed, but it’s a nice example… here I made a typo on Imputators.jl row 154, but nowhere in the stacktrace this position is reported… Is there any package that can help durin…

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## [LinearAlgebra.det and symbolic variables](https://discourse.julialang.org/t/linearalgebra-det-and-symbolic-variables/83054)

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**Author:** [@DanDoe](https://discourse.julialang.org/u/DanDoe)\
**Replies:** 6\
**Last updated:** [June 22, 2022, 3:34pm UTC](https://discourse.julialang.org/t/linearalgebra-det-and-symbolic-variables/83054 "2022-06-22T15:34:08Z")

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I am interested in the computation of the determinant of a (very sparse) matrix involving a symbolic variable. My code is using Symbolics, LinearAlgebra, SparseArrays N = 11 FloatType = Float64 c = zeros(FloatType, …

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## [@async while loop not looping](https://discourse.julialang.org/t/async-while-loop-not-looping/83156)

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**Author:** [@wiseac](https://discourse.julialang.org/u/wiseac)\
**Replies:** 2\
**Last updated:** [June 22, 2022, 2:17pm UTC](https://discourse.julialang.org/t/async-while-loop-not-looping/83156 "2022-06-22T14:17:33Z")

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Im trying to loop two tasks but it will only run through it once and not loop. This is what my code looks like. I have the second task commented out because im trying to just get the first one working. If i remove the @…

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## [Julia Gender Inclusive coffee meet-up with Xuan](https://discourse.julialang.org/t/julia-gender-inclusive-coffee-meet-up-with-xuan/83183)

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**Author:** [@kimauth](https://discourse.julialang.org/u/kimauth)\
**Replies:** 0\
**Last updated:** [June 22, 2022, 1:50pm UTC](https://discourse.julialang.org/t/julia-gender-inclusive-coffee-meet-up-with-xuan/83183 "2022-06-22T13:50:34Z")

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Logical reasoning in Julia Hey everyone, Julia Gender Inclusive invites you to the next coffee meetup on sunday, 26nd of June at 11AM EDT / 3pm UTC / 5pm CEST / 8:30 pm IST! Sign-up here for a link to join: https://for…

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## [Next run of the computational thinking course?](https://discourse.julialang.org/t/next-run-of-the-computational-thinking-course/71684)

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**Author:** [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Replies:** 4\
**Last updated:** [June 22, 2022, 12:43pm UTC](https://discourse.julialang.org/t/next-run-of-the-computational-thinking-course/71684 "2022-06-22T12:43:44Z")

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While the course material is always available, I learned that to learn in an online course, I need the schedule of a “real course”, with lessons coming up at certain days and exercises due for day xxx. So I wander if th…

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## [Plot different length data together in Gadfly](https://discourse.julialang.org/t/plot-different-length-data-together-in-gadfly/77036)

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**Author:** [@Nathan\_Boyer](https://discourse.julialang.org/u/Nathan_Boyer)\
**Replies:** 8\
**Last updated:** [June 22, 2022, 12:33pm UTC](https://discourse.julialang.org/t/plot-different-length-data-together-in-gadfly/77036 "2022-06-22T12:33:00Z")

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I am struggling to plot two different (x,y) lines together with a single plot command and the default color palette, since apparently I can’t give the layers label = "Data Label" like in Plots.jl. What is the best way to…

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## [Stipple.jl embedding of a local image in the html dashboard](https://discourse.julialang.org/t/stipple-jl-embedding-of-a-local-image-in-the-html-dashboard/83157)

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**Author:** [@monty](https://discourse.julialang.org/u/monty)\
**Replies:** 1\
**Last updated:** [June 22, 2022, 12:26pm UTC](https://discourse.julialang.org/t/stipple-jl-embedding-of-a-local-image-in-the-html-dashboard/83157 "2022-06-22T12:26:12Z")

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What will be the easiest way to embed a local image (generated on the compute server by Julia) in the HTML dashboard? I have found solutions using a “public” folder however it is unclear to me (1) where it should be loc…

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## [Profiling compilation of a large generated expression?](https://discourse.julialang.org/t/profiling-compilation-of-a-large-generated-expression/83179)

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**Author:** [@iago-lito](https://discourse.julialang.org/u/iago-lito)\
**Replies:** 4\
**Last updated:** [June 22, 2022, 11:32am UTC](https://discourse.julialang.org/t/profiling-compilation-of-a-large-generated-expression/83179 "2022-06-22T11:32:34Z")

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Hi @Julia, The team I’m working with is writing a simulation package, with a core dudt!(du, u, parameters, t) function given as an argument to ODEProblem and solve from DifferentialEquations. The code in dudt! is comple…

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## [Solution at specific time points using a stiff ODE solver](https://discourse.julialang.org/t/solution-at-specific-time-points-using-a-stiff-ode-solver/83169)

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**Author:** [@ajaydeepk](https://discourse.julialang.org/u/ajaydeepk)\
**Replies:** 2\
**Last updated:** [June 22, 2022, 10:57am UTC](https://discourse.julialang.org/t/solution-at-specific-time-points-using-a-stiff-ode-solver/83169 "2022-06-22T10:57:51Z")

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While using stiff ODE solver like CVODE\_BDF() and radau(), can we use saveat to save solutions at specific time points. For example, since time step dt changes adaptively, thereby is it a good idea to do sol = solve(fun…

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## [Internet browser enabled visualization](https://discourse.julialang.org/t/internet-browser-enabled-visualization/82575)

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**Author:** [@grimon](https://discourse.julialang.org/u/grimon)\
**Replies:** 1\
**Last updated:** [June 22, 2022, 10:44am UTC](https://discourse.julialang.org/t/internet-browser-enabled-visualization/82575 "2022-06-22T10:44:57Z")

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I have created a visualization that displays in a local window using Graphs, Blink, and WebIO. Is there an easy way for me to convert what I have written into something that will display on a webpage? This is the code t…

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## [Impossible actions in POMDPs.jl](https://discourse.julialang.org/t/impossible-actions-in-pomdps-jl/80662)

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**Author:** [@vamp](https://discourse.julialang.org/u/vamp)\
**Replies:** 3\
**Last updated:** [May 14, 2022, 5:37pm UTC](https://discourse.julialang.org/t/impossible-actions-in-pomdps-jl/80662 "2022-05-14T17:37:34Z")

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Hello, For POMDPs.jl I have a big state space (bigger than 2.000 possible states). From certain states, I cannot take some actions, that is state-dependent actions. I have check the documentation (link here). And for T…

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## [Julian way to "remove" missing type in the eltype of a Matrix?](https://discourse.julialang.org/t/julian-way-to-remove-missing-type-in-the-eltype-of-a-matrix/83168)

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**Author:** [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Replies:** 7\
**Last updated:** [June 22, 2022, 8:48am UTC](https://discourse.julialang.org/t/julian-way-to-remove-missing-type-in-the-eltype-of-a-matrix/83168 "2022-06-22T08:48:30Z")

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julia\> A = \[1 2 missing; 4 5 6\] 2×3 Matrix{Union{Missing, Int64}}: 1 2 missing 4 5 6 julia\> A\[1,3\] = 3 3 julia\> A 2×3 Matrix{Union{Missing, Int64}}: 1 2 3 4 5 6 Now, I want to get rid of the missing in th…

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## [I am getting error while running simple code](https://discourse.julialang.org/t/i-am-getting-error-while-running-simple-code/83166)

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**Author:** [@raamsa](https://discourse.julialang.org/u/raamsa)\
**Replies:** 2\
**Last updated:** [June 22, 2022, 8:39am UTC](https://discourse.julialang.org/t/i-am-getting-error-while-running-simple-code/83166 "2022-06-22T08:39:29Z")

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I have started to learn Julia. And I made a simple program using the function to find the area of the square. The code is below # Given the length of square function areaOfsquare() global s= input("Enter the length …

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## [How are invalidated MethodInstances found, and how well does the process scale?](https://discourse.julialang.org/t/how-are-invalidated-methodinstances-found-and-how-well-does-the-process-scale/83099)

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**Author:** [@Benny](https://discourse.julialang.org/u/Benny)\
**Replies:** 7\
**Last updated:** [June 22, 2022, 7:54am UTC](https://discourse.julialang.org/t/how-are-invalidated-methodinstances-found-and-how-well-does-the-process-scale/83099 "2022-06-22T07:54:52Z")

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From what I understand, compiled methods (for clarity I’ll call them MethodInstances) are invalidated when methods are defined, e.g. f(x) = 1; f(1); f(x::Real) = 2. I imagine the most wasteful algorithm would be to check…

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## [HTTP Streaming Chunked JSON](https://discourse.julialang.org/t/http-streaming-chunked-json/82797)

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**Author:** [@JohnDuffy](https://discourse.julialang.org/u/JohnDuffy)\
**Replies:** 7\
**Last updated:** [June 22, 2022, 7:54am UTC](https://discourse.julialang.org/t/http-streaming-chunked-json/82797 "2022-06-22T07:54:34Z")

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Hi I receive streamed new-line delimited JSON data from a REST API. The data is streamed in chunks and full line of JSON may span multiple chunks. So, I need to somehow buffer the chunks as they arrive until I have a f…

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## [How to animate a slider in GLMakie?](https://discourse.julialang.org/t/how-to-animate-a-slider-in-glmakie/83151)

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**Author:** [@Willi\_Wespe](https://discourse.julialang.org/u/Willi_Wespe)\
**Replies:** 2\
**Last updated:** [June 22, 2022, 7:35am UTC](https://discourse.julialang.org/t/how-to-animate-a-slider-in-glmakie/83151 "2022-06-22T07:35:57Z")

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Hi, I want to animate a slider when I press a button. The slider should move from a start value to an end value, but it jumps right to the end, though I use sleep, and checked that the for loop works correct. using GL…

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## [\[ANN\] Training course "Julia for HPC" in Stuttgart, Germany on Sep 20-23, 2022](https://discourse.julialang.org/t/ann-training-course-julia-for-hpc-in-stuttgart-germany-on-sep-20-23-2022/83111)

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**Author:** [@sloede](https://discourse.julialang.org/u/sloede)\
**Replies:** 3\
**Last updated:** [June 22, 2022, 7:20am UTC](https://discourse.julialang.org/t/ann-training-course-julia-for-hpc-in-stuttgart-germany-on-sep-20-23-2022/83111 "2022-06-22T07:20:07Z")

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Hey everyone! At HLRS we are offering a new “Julia for High-Performance Computing” course, which will take place on-site at the High-Performance Computing Center Stuttgart (HLRS) in Stuttgart, Germany from September 20t…

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## [Different Errors on CI and local machine](https://discourse.julialang.org/t/different-errors-on-ci-and-local-machine/83120)

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**Author:** [@fbanning](https://discourse.julialang.org/u/fbanning)\
**Replies:** 3\
**Last updated:** [June 22, 2022, 6:22am UTC](https://discourse.julialang.org/t/different-errors-on-ci-and-local-machine/83120 "2022-06-22T06:22:13Z")

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I’m encountering an issue with CI on github. If I define julia\> foo(x) = nothing foo (generic function with 1 method) and do a @test\_throws with it, I would expect it to throw a MethodError like here julia\> foo(; x =…

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## [Simple example of @threads](https://discourse.julialang.org/t/simple-example-of-threads/83049)

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**Author:** [@amrods](https://discourse.julialang.org/u/amrods)\
**Replies:** 17\
**Last updated:** [June 22, 2022, 6:11am UTC](https://discourse.julialang.org/t/simple-example-of-threads/83049 "2022-06-22T06:11:06Z")

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How can I make this simple example thread safe? function func(R=5) s = 0.0 Threads.@threads :static for i in 1:R s += 1 end return s end If it makes any difference, in my application I am summin…

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## [Canonical way on how to use something that is defined later in the code?](https://discourse.julialang.org/t/canonical-way-on-how-to-use-something-that-is-defined-later-in-the-code/83142)

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**Author:** [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Replies:** 2\
**Last updated:** [June 22, 2022, 5:21am UTC](https://discourse.julialang.org/t/canonical-way-on-how-to-use-something-that-is-defined-later-in-the-code/83142 "2022-06-22T05:21:38Z")

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I have a package that is divided in several modules, says Utils and 'Algos\`, each on his file: MyPackage.jl: include("Utils.jl") include("Algos.jl") Up to now Algos was using something defined in Utils, and there were…

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## [Using a variable graph structure with NeuralODE and GCNConv](https://discourse.julialang.org/t/using-a-variable-graph-structure-with-neuralode-and-gcnconv/78881)

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**Author:** [@Zapientus](https://discourse.julialang.org/u/Zapientus)\
**Replies:** 3\
**Last updated:** [June 22, 2022, 4:56am UTC](https://discourse.julialang.org/t/using-a-variable-graph-structure-with-neuralode-and-gcnconv/78881 "2022-06-22T04:56:20Z")

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Hello everyone, I have recently been working with Graph Neural Ordinary Differential Equations for structure predictions of proteins. This has been working quite well as long as the graph structure is fixed and given to…

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## [Colorized objects when tab completing module](https://discourse.julialang.org/t/colorized-objects-when-tab-completing-module/83160)

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**Author:** [@mwhisena](https://discourse.julialang.org/u/mwhisena)\
**Replies:** 0\
**Last updated:** [June 22, 2022, 4:41am UTC](https://discourse.julialang.org/t/colorized-objects-when-tab-completing-module/83160 "2022-06-22T04:41:51Z")

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I think that it would be useful if Julia colorized the results when tab completing in the REPL. For instance, in the package Flux.jl one can simply do in REPL Flux. and then TAB to view all objects that were loaded fro…

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## [How to import custom module from file without include](https://discourse.julialang.org/t/how-to-import-custom-module-from-file-without-include/83139)

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**Author:** [@Jack\_N](https://discourse.julialang.org/u/Jack_N)\
**Replies:** 5\
**Last updated:** [June 22, 2022, 4:27am UTC](https://discourse.julialang.org/t/how-to-import-custom-module-from-file-without-include/83139 "2022-06-22T04:27:35Z")

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I made a custom module in a file database.jl called DecisionNode but I cannot seem to find a way to import the DecisionNode module without using the include function, which I do not want to do since I will be using the D…

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## [Substitute powers and powers of fractions](https://discourse.julialang.org/t/substitute-powers-and-powers-of-fractions/80641)

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**Author:** [@kjellqvist](https://discourse.julialang.org/u/kjellqvist)\
**Replies:** 4\
**Last updated:** [June 22, 2022, 2:36am UTC](https://discourse.julialang.org/t/substitute-powers-and-powers-of-fractions/80641 "2022-06-22T02:36:22Z")

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I’m a bit stuck on substitutions, for example: @variables x y eq = (1/x)^2 substitute(eq, Dict(\[1/x =\> y\])) julia\> y^2 whereas @variables x y eq = 1/x^2 substitute(eq, Dict(\[1/x =\> y\])) julia\> 1 / (x^2) I w…

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## [How to find single solution for this system of linear inequalities?](https://discourse.julialang.org/t/how-to-find-single-solution-for-this-system-of-linear-inequalities/83149)

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**Author:** [@Bobberson3108](https://discourse.julialang.org/u/Bobberson3108)\
**Replies:** 2\
**Last updated:** [June 22, 2022, 1:59am UTC](https://discourse.julialang.org/t/how-to-find-single-solution-for-this-system-of-linear-inequalities/83149 "2022-06-22T01:59:26Z")

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I’m trying to solve a set of modular inequalities using JuMP by replacing the modulus with variables m and n. I’ve tried multiple different solvers but they’re all much too slow. I just want to find any singular solution…

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## [ERROR: TypeError: non-boolean (Missing) used in boolean context](https://discourse.julialang.org/t/error-typeerror-non-boolean-missing-used-in-boolean-context/83152)

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**Author:** [@jar1](https://discourse.julialang.org/u/jar1)\
**Replies:** 5\
**Last updated:** [June 22, 2022, 1:56am UTC](https://discourse.julialang.org/t/error-typeerror-non-boolean-missing-used-in-boolean-context/83152 "2022-06-22T01:56:59Z")

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Why does this happen? julia\> 3 \< missing \< 5 ERROR: TypeError: non-boolean (Missing) used in boolean context Is it expanding to this? julia\> (3 \< missing) && (missing \< 5) ERROR: TypeError: non-boolean (Missing) used …

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## [Use a time-series as parameter of ODEProblem](https://discourse.julialang.org/t/use-a-time-series-as-parameter-of-odeproblem/82945)

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**Author:** [@Songio](https://discourse.julialang.org/u/Songio)\
**Replies:** 13\
**Last updated:** [June 22, 2022, 12:01am UTC](https://discourse.julialang.org/t/use-a-time-series-as-parameter-of-odeproblem/82945 "2022-06-22T00:01:33Z")

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Hello, I am quite new to Julia and I would like to use it to solve some ODE problems. Let’s take the following example: function test!(du,u,p,t) yield = 10 decay = 5 du\[1\] = yield\*p - decay\*u\[1\] end I can…

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## [Array of pointers to struct vs. Array of struct](https://discourse.julialang.org/t/array-of-pointers-to-struct-vs-array-of-struct/83150)

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**Author:** [@peter.wolf](https://discourse.julialang.org/u/peter.wolf)\
**Replies:** 2\
**Last updated:** [June 21, 2022, 11:29pm UTC](https://discourse.julialang.org/t/array-of-pointers-to-struct-vs-array-of-struct/83150 "2022-06-21T23:29:54Z")

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I want to create a vector of structs. In my code I do something like this some\_vector = Vector{SomeStruct}(big\_number) for i in 1:big\_number some\_vector\[i\] = SomeStruct(some\_args) end I believe this is allocating …

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## [PkgTemplates.jl is not updated to my configurations in global Git config](https://discourse.julialang.org/t/pkgtemplates-jl-is-not-updated-to-my-configurations-in-global-git-config/83146)

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**Author:** [@Veenty](https://discourse.julialang.org/u/Veenty)\
**Replies:** 1\
**Last updated:** [June 21, 2022, 10:01pm UTC](https://discourse.julialang.org/t/pkgtemplates-jl-is-not-updated-to-my-configurations-in-global-git-config/83146 "2022-06-21T22:01:10Z")

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So I have updated my configurations in global Git config (they where incomplete before) and now I would like for PkgTemplate to read this information, as is suppose to, the issue is that when I do t = Template() t("MyPk…

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## [NLopt :FORCED\_STOP when objective function has wrong signature (missing gradient arg)](https://discourse.julialang.org/t/nlopt-forced-stop-when-objective-function-has-wrong-signature-missing-gradient-arg/82742)

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**Author:** [@pierre-haessig](https://discourse.julialang.org/u/pierre-haessig)\
**Replies:** 2\
**Last updated:** [June 21, 2022, 9:00pm UTC](https://discourse.julialang.org/t/nlopt-forced-stop-when-objective-function-has-wrong-signature-missing-gradient-arg/82742 "2022-06-21T21:00:01Z")

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Hello, I just faced a small usability issue using NLopt.jl. I believe the issue is common enough (e.g. forum post from Oct 2020 https://discourse.julialang.org/t/nlopt-forced-stop) that it may suggest a better error cat…

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