# Latest

**URL:** https://discourse.julialang.org/latest.md?page=643

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

**Page:** 644

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## [How can I combine Cairo frames into a GIF?](https://discourse.julialang.org/t/how-can-i-combine-cairo-frames-into-a-gif/101704)

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**Author:** [@djpell](https://discourse.julialang.org/u/djpell)\
**Replies:** 3\
**Last updated:** [July 17, 2023, 9:15pm UTC](https://discourse.julialang.org/t/how-can-i-combine-cairo-frames-into-a-gif/101704 "2023-07-17T21:15:48Z")

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I have used Cairo to create a series of drawings collected into an array. I would like to combine all of these images into a GIF. FileIO allows me to convert one single frame into a PNG with FileIO.save("test.png", img…

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## [Should we disallow non-compliant \`AbstractUnitRange\`s where \`typeof(step)\` doesn't match the \`eltype\`?](https://discourse.julialang.org/t/should-we-disallow-non-compliant-abstractunitrange-s-where-typeof-step-doesnt-match-the-eltype/101695)

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**Author:** [@jishnub](https://discourse.julialang.org/u/jishnub)\
**Replies:** 7\
**Last updated:** [July 17, 2023, 8:13pm UTC](https://discourse.julialang.org/t/should-we-disallow-non-compliant-abstractunitrange-s-where-typeof-step-doesnt-match-the-eltype/101695 "2023-07-17T20:13:33Z")

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Currently, the docstring for AbstractUnitRange states: AbstractUnitRange{T} \<: OrdinalRange{T, T} Supertype for ranges with a step size of \`oneunit(T)\` with elements of type \`T\`. This implies that the step must be…

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## [Arrow stream usage clarification](https://discourse.julialang.org/t/arrow-stream-usage-clarification/89508)

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**Author:** [@jeremiedb](https://discourse.julialang.org/u/jeremiedb)\
**Replies:** 10\
**Last updated:** [July 17, 2023, 7:55pm UTC](https://discourse.julialang.org/t/arrow-stream-usage-clarification/89508 "2023-07-17T19:55:57Z")

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I’m trying to use Arrow’s Stream https://arrow.juliadata.org/dev/reference/#Arrow.Stream to get an efficient out of RAM tabular data iterator. However, attempts to iterate over the arrow stream only appear to perform a …

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## [\[ANN\] TestingUtilities.jl](https://discourse.julialang.org/t/ann-testingutilities-jl/99121)

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**Author:** [@curtd](https://discourse.julialang.org/u/curtd)\
**Replies:** 6\
**Last updated:** [July 17, 2023, 4:41pm UTC](https://discourse.julialang.org/t/ann-testingutilities-jl/99121 "2023-07-17T16:41:00Z")

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Hey all, I’m happy to announce TestingUtilities.jl, which provides macros to (hopefully) make your package testing experience a lot smoother. This package is set to be registered in the General registry in two days as o…

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## [Produce a heatmap for agents on a 2d grid with abmplot](https://discourse.julialang.org/t/produce-a-heatmap-for-agents-on-a-2d-grid-with-abmplot/101638)

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**Author:** [@mantzaris](https://discourse.julialang.org/u/mantzaris)\
**Replies:** 3\
**Last updated:** [July 17, 2023, 4:13pm UTC](https://discourse.julialang.org/t/produce-a-heatmap-for-agents-on-a-2d-grid-with-abmplot/101638 "2023-07-17T16:13:39Z")

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Given a agent based model (using Agents.jl) of agents on a 2d grid with values between 0-10 (continuous) is it possible to produce a heatmap using abmplot? (each agent has a Float param) If so what is a straightforward a…

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## [Interest in RNA-seq specific convenience package based on BioJulia?](https://discourse.julialang.org/t/interest-in-rna-seq-specific-convenience-package-based-on-biojulia/96949)

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**Author:** [@maltesie](https://discourse.julialang.org/u/maltesie)\
**Replies:** 16\
**Last updated:** [July 17, 2023, 4:11pm UTC](https://discourse.julialang.org/t/interest-in-rna-seq-specific-convenience-package-based-on-biojulia/96949 "2023-07-17T16:11:13Z")

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Hi all, I’m working in Bioinformatics research and started using Julia 2 years ago and now use it as my main language for everything I do. I organize the reusable part of my code in form of a Julia package which I try t…

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## [\[ANN\] OneTwoMany.jl](https://discourse.julialang.org/t/ann-onetwomany-jl/101623)

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**Author:** [@oschulz](https://discourse.julialang.org/u/oschulz)\
**Replies:** 16\
**Last updated:** [July 17, 2023, 3:02pm UTC](https://discourse.julialang.org/t/ann-onetwomany-jl/101623 "2023-07-17T15:02:25Z")

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I’ve put together a tiny package OneTwoMany.jl - that provides a function getsecond, as well as functions first\_and\_rest and first\_second\_rest. Julia provides the functions first and last , but not second (except for Da…

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## [Solving a differential equation with asymptotic boundary condition](https://discourse.julialang.org/t/solving-a-differential-equation-with-asymptotic-boundary-condition/101688)

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**Author:** [@Nek](https://discourse.julialang.org/u/Nek)\
**Replies:** 1\
**Last updated:** [July 17, 2023, 2:16pm UTC](https://discourse.julialang.org/t/solving-a-differential-equation-with-asymptotic-boundary-condition/101688 "2023-07-17T14:16:31Z")

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I am currently working on a project to solve a differential equation. The differential equation is like: \\frac{d^2f}{dt^2} + F\[f\] \\left( \\frac{df}{dt} \\right)^2 + G\[f\] \\frac{df}{dt} + H\[f\] = 0, and with conditions f…

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## [Define multiple methods or one method with union types?](https://discourse.julialang.org/t/define-multiple-methods-or-one-method-with-union-types/101674)

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**Author:** [@kunzaatko](https://discourse.julialang.org/u/kunzaatko)\
**Replies:** 4\
**Last updated:** [July 17, 2023, 2:03pm UTC](https://discourse.julialang.org/t/define-multiple-methods-or-one-method-with-union-types/101674 "2023-07-17T14:03:17Z")

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What is the preferred way to implement methods that allow multiple types? Option A: function method(a::Union{Tuple{Integer,Integer}, Integer}, b::Union{Tuple{Integer,Integer}, Integer}) a = a isa Integer ? (a,a) : …

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## [Iterating over elements of upper triangular matrix, but cartesian indices are needed](https://discourse.julialang.org/t/iterating-over-elements-of-upper-triangular-matrix-but-cartesian-indices-are-needed/65498)

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**Author:** [@lmiq](https://discourse.julialang.org/u/lmiq)\
**Replies:** 17\
**Last updated:** [July 17, 2023, 1:13pm UTC](https://discourse.julialang.org/t/iterating-over-elements-of-upper-triangular-matrix-but-cartesian-indices-are-needed/65498 "2023-07-17T13:13:46Z")

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Basically what I (think) I need is this function: https://stackoverflow.com/questions/27086195/linear-index-upper-triangular-matrix Of course I can just implement it, two lines of code. But that seems something that pr…

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## [Lux.jl Neural ODE Initial Condition Optimization](https://discourse.julialang.org/t/lux-jl-neural-ode-initial-condition-optimization/95207)

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**Author:** [@George\_Stepaniants](https://discourse.julialang.org/u/George_Stepaniants)\
**Replies:** 14\
**Last updated:** [July 17, 2023, 12:55pm UTC](https://discourse.julialang.org/t/lux-jl-neural-ode-initial-condition-optimization/95207 "2023-07-17T12:55:11Z")

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How do we also optimize the initial condition of a neural ODE using Lux.jl? I have not been able to find any examples of this. Is there any way to just add the initial conditions as parameters to a neural ODE that is def…

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## [How does a nested function display its local name only when assigned to a matching global name?](https://discourse.julialang.org/t/how-does-a-nested-function-display-its-local-name-only-when-assigned-to-a-matching-global-name/101685)

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**Author:** [@Benny](https://discourse.julialang.org/u/Benny)\
**Replies:** 1\
**Last updated:** [July 17, 2023, 7:59am UTC](https://discourse.julialang.org/t/how-does-a-nested-function-display-its-local-name-only-when-assigned-to-a-matching-global-name/101685 "2023-07-17T07:59:14Z")

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v1.8.3 MWE: julia\> function gh(n) g() = n h = () -\> n g, h end gh (generic function with 1 method) julia\> g2, h2 = gh(1) (var"#g#2"{Int64}(1), var"#1#3"{Int64}(1)) julia\> g, h = g2, h…

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## [How daggerflux works?](https://discourse.julialang.org/t/how-daggerflux-works/101687)

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**Author:** [@Tomas\_Pevny](https://discourse.julialang.org/u/Tomas_Pevny)\
**Replies:** 1\
**Last updated:** [July 17, 2023, 6:28am UTC](https://discourse.julialang.org/t/how-daggerflux-works/101687 "2023-07-17T06:28:11Z")

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Dear All, @dhairyagandhi96 Manytimes in past, I wanted to use GitHub - FluxML/DaggerFlux.jl: Distributed computation of differentiation pipelines to use multiple workers, devices, GPU, etc. since Julia wasn't fast enou…

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## [Is there a way to incorporate time series data into coupled ODE system using DifferentialEquations.jl?](https://discourse.julialang.org/t/is-there-a-way-to-incorporate-time-series-data-into-coupled-ode-system-using-differentialequations-jl/101682)

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**Author:** [@PeX](https://discourse.julialang.org/u/PeX)\
**Replies:** 3\
**Last updated:** [July 17, 2023, 2:18am UTC](https://discourse.julialang.org/t/is-there-a-way-to-incorporate-time-series-data-into-coupled-ode-system-using-differentialequations-jl/101682 "2023-07-17T02:18:10Z")

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Hi all, If I have a set of coupled ODE: x = f(y, \\dot{y}, \\dot{x}), y = f(x, \\dot{x}, \\dot{y}) and I have a time series data for x, is there a way to implement this constraint into the solver? I was looking at the d…

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## [Understanding few lines from NeuralPDE.jl PDE example (phi solution)](https://discourse.julialang.org/t/understanding-few-lines-from-neuralpde-jl-pde-example-phi-solution/101499)

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**Author:** [@PeX](https://discourse.julialang.org/u/PeX)\
**Replies:** 3\
**Last updated:** [July 16, 2023, 11:58pm UTC](https://discourse.julialang.org/t/understanding-few-lines-from-neuralpde-jl-pde-example-phi-solution/101499 "2023-07-16T23:58:24Z")

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Hi all, first time I’m trying to use PINNs with Julia, as I’m reading the docs there are some parts that I’m missing. In this example : I see that the lines used for the predictions are: phi = discretization.phi u\_p…

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## [\[ANN\] Arceus.jl Efficient runtime trait library](https://discourse.julialang.org/t/ann-arceus-jl-efficient-runtime-trait-library/101650)

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**Author:** [@Tarny\_GG\_Channie](https://discourse.julialang.org/u/Tarny_GG_Channie)\
**Replies:** 3\
**Last updated:** [July 16, 2023, 11:51pm UTC](https://discourse.julialang.org/t/ann-arceus-jl-efficient-runtime-trait-library/101650 "2023-07-16T23:51:58Z")

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This is my first package. Wish me good luck. This package was awkwardly developed and is really cursed internally. Hopefully it’s still usable. Please star it if you like it.

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## [Implementing a new performant Entity Component System (ECS). (Please request the features you want)](https://discourse.julialang.org/t/implementing-a-new-performant-entity-component-system-ecs-please-request-the-features-you-want/99109)

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**Author:** [@Tarny\_GG\_Channie](https://discourse.julialang.org/u/Tarny_GG_Channie)\
**Replies:** 6\
**Last updated:** [July 16, 2023, 11:27pm UTC](https://discourse.julialang.org/t/implementing-a-new-performant-entity-component-system-ecs-please-request-the-features-you-want/99109 "2023-07-16T23:27:32Z")

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Julia provides a good compile-time dispatch, however, when a run-time dispatch is required, Julia is not so fast. While Overseer provides a possible solution, it is about updating an entire system at a time, and while it…

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## [Simple function using Zygote gradient is type-unstable](https://discourse.julialang.org/t/simple-function-using-zygote-gradient-is-type-unstable/101677)

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**Author:** [@Thaegy](https://discourse.julialang.org/u/Thaegy)\
**Replies:** 9\
**Last updated:** [July 16, 2023, 10:47pm UTC](https://discourse.julialang.org/t/simple-function-using-zygote-gradient-is-type-unstable/101677 "2023-07-16T22:47:34Z")

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Hi there, I have been trying to figure out why when I use Zygote to calculate the gradient of a simple function it returns the correct value but if I used @code\_warntype it suggests the function is type-unstable and is r…

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## [How to analyse the complexity of a Julia project?](https://discourse.julialang.org/t/how-to-analyse-the-complexity-of-a-julia-project/101678)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 4\
**Last updated:** [July 16, 2023, 8:05pm UTC](https://discourse.julialang.org/t/how-to-analyse-the-complexity-of-a-julia-project/101678 "2023-07-16T20:05:54Z")

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In the past I used sloccount, but it does not even know of Julia, it thinks it is lisp (ok, not totally wrong). I would like to know: number of source code files lines of source code dito without comments and blank li…

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## [\[ANN\] SuffixConversion.jl - make it easier to write generic code with numerical literals](https://discourse.julialang.org/t/ann-suffixconversion-jl-make-it-easier-to-write-generic-code-with-numerical-literals/101679)

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**Author:** [@simonbyrne](https://discourse.julialang.org/u/simonbyrne)\
**Replies:** 6\
**Last updated:** [July 16, 2023, 7:24pm UTC](https://discourse.julialang.org/t/ann-suffixconversion-jl-make-it-easier-to-write-generic-code-with-numerical-literals/101679 "2023-07-16T19:24:25Z")

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I’m announcing SuffixConversion.jl, which aims to make it easier to write generic code involving numeric literals without unintentional type promotion. An example: using SuffixConversion function addhalf(x) @suffix…

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## [Documenter.jl: Missing Docstring (random?)](https://discourse.julialang.org/t/documenter-jl-missing-docstring-random/101619)

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**Author:** [@lmiq](https://discourse.julialang.org/u/lmiq)\
**Replies:** 4\
**Last updated:** [July 16, 2023, 6:41pm UTC](https://discourse.julialang.org/t/documenter-jl-missing-docstring-random/101619 "2023-07-16T18:41:29Z")

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In this package, I reference some doc strings, as usual with @docs macro. Locally, using the LiveServer.servedocs(), some docstrings do not show up, but some of these show up when the documentation is actually deployed. …

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## [How to handle HTTP.Exceptions.StatusError](https://discourse.julialang.org/t/how-to-handle-http-exceptions-statuserror/101649)

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**Author:** [@raman\_kumar](https://discourse.julialang.org/u/raman_kumar)\
**Replies:** 16\
**Last updated:** [July 16, 2023, 5:17pm UTC](https://discourse.julialang.org/t/how-to-handle-http-exceptions-statuserror/101649 "2023-07-16T17:17:10Z")

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I am getting HTTP.Exceptions.StatusError using CSV, DataFrames,HTTP begin for x in 33047:33187 url="https://gcn.nasa.gov/circulars/$x" txt=String((HTTP.get(url))) if occursin("report …

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## [Handling an overflow example in QuadGK](https://discourse.julialang.org/t/handling-an-overflow-example-in-quadgk/101657)

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**Author:** [@stevengj](https://discourse.julialang.org/u/stevengj)\
**Replies:** 5\
**Last updated:** [July 16, 2023, 2:06pm UTC](https://discourse.julialang.org/t/handling-an-overflow-example-in-quadgk/101657 "2023-07-16T14:06:11Z")

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Someone asked me this question over email, and I decided to post my answer here since it might be of more general interest. Suppose that we are trying to compute \\int\_0^\\infty (e^y - 1) \\frac{e^{-2.5y}}{y^{1.2}} dy. Th…

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## [How to generate white noise?](https://discourse.julialang.org/t/how-to-generate-white-noise/101673)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 1\
**Last updated:** [July 16, 2023, 12:38pm UTC](https://discourse.julialang.org/t/how-to-generate-white-noise/101673 "2023-07-16T12:38:24Z")

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I need some white noise, which I then can shape to have the required spectrum using filters. But how to I generate white noise? I could do it using rand or randn: noise1=rand(Int(1e6)).-0.5 noise2=randn(Int(1e6)) I ge…

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## [How to perform Algrebraic operations on "IntervalBox.()"?](https://discourse.julialang.org/t/how-to-perform-algrebraic-operations-on-intervalbox/101661)

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**Author:** [@Ashu](https://discourse.julialang.org/u/Ashu)\
**Replies:** 0\
**Last updated:** [July 15, 2023, 7:15pm UTC](https://discourse.julialang.org/t/how-to-perform-algrebraic-operations-on-intervalbox/101661 "2023-07-15T19:15:38Z")

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Hello All, There are two interval box X = IntervalBox.(0..5, 5..10, 10..15) and Y=IntervalBox.(-5..3, 11..13, 7..11). Please let me know how to do elementwise union, and intersection between the two IntervalBoxes Inter…

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## [Hcat without copy and stack overflow in type inference](https://discourse.julialang.org/t/hcat-without-copy-and-stack-overflow-in-type-inference/101671)

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**Author:** [@xgdgsc](https://discourse.julialang.org/u/xgdgsc)\
**Replies:** 3\
**Last updated:** [July 16, 2023, 10:11am UTC](https://discourse.julialang.org/t/hcat-without-copy-and-stack-overflow-in-type-inference/101671 "2023-07-16T10:11:48Z")

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When using packages like ArrayPartition in GitHub - SciML/RecursiveArrayTools.jl: Tools for easily handling objects like arrays of arrays and deeper nestings in scientific machine learning (SciML) and other applications …

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## [FFTW plan applied to array with wrong memory alignment](https://discourse.julialang.org/t/fftw-plan-applied-to-array-with-wrong-memory-alignment/101672)

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**Author:** [@ymtoo](https://discourse.julialang.org/u/ymtoo)\
**Replies:** 0\
**Last updated:** [July 16, 2023, 9:43am UTC](https://discourse.julialang.org/t/fftw-plan-applied-to-array-with-wrong-memory-alignment/101672 "2023-07-16T09:43:30Z")

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MWE: using ChainRulesCore: @ignore\_derivatives using DSP using DSP.Periodograms: forward\_plan using Zygote function mystft(x::AbstractVector{T}, n, noverlap) where {T} numsamples = length(x) numframes = numsamp…

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## [Make fixing tests easier](https://discourse.julialang.org/t/make-fixing-tests-easier/101610)

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**Author:** [@Impressium](https://discourse.julialang.org/u/Impressium)\
**Replies:** 6\
**Last updated:** [July 16, 2023, 7:11am UTC](https://discourse.julialang.org/t/make-fixing-tests-easier/101610 "2023-07-16T07:11:06Z")

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Hi all :slight\_smile: I’m currently fixing lot’s of tests. It’s quite annoying xD To questions: is there any UI to polish and sort the stack traces is there a setting in the test PKG to enable debug mode. So that at …

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## [Random number generation from a power law](https://discourse.julialang.org/t/random-number-generation-from-a-power-law/100701)

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**Author:** [@ABCD](https://discourse.julialang.org/u/ABCD)\
**Replies:** 6\
**Last updated:** [July 16, 2023, 7:09am UTC](https://discourse.julialang.org/t/random-number-generation-from-a-power-law/100701 "2023-07-16T07:09:15Z")

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hello all, I am new to Julia. I need to generate random numbers from power law, broken power law and different distributions. Is there a package that do all of these? Thank you very much in advance.

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## [Efficiently computing Hessians of Neural Networks output with respect to inputs](https://discourse.julialang.org/t/efficiently-computing-hessians-of-neural-networks-output-with-respect-to-inputs/101666)

<div class="topic-metadata">

**Author:** [@Baba\_Yara\_Fahiz](https://discourse.julialang.org/u/Baba_Yara_Fahiz)\
**Replies:** 1\
**Last updated:** [July 16, 2023, 5:29am UTC](https://discourse.julialang.org/t/efficiently-computing-hessians-of-neural-networks-output-with-respect-to-inputs/101666 "2023-07-16T05:29:44Z")

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Hello everyone, I’m currently working on a problem that involves approximating a partial differential equation using neural networks. I’ve created a script that generates a set of neural networks, computes their outputs…

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