**Author:** [@Alseidon](https://discourse.julialang.org/u/Alseidon)\
**Replies:** 4\
**Last updated:** [January 9, 2024, 8:53am UTC](https://discourse.julialang.org/t/how-to-optimize-struct-for-speed/108518 "2024-01-09T08:53:05Z")
I am defining a new struct for a project, which I need to be fast. This struct only contains one parameter, an MVector (from the StaticArrays.jl package). However, the operations on the struct are 4x slower than those on…
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## [How use the dependent lags part in solving ddes](https://discourse.julialang.org/t/how-use-the-dependent-lags-part-in-solving-ddes/108246)
**Author:** [@Ananya\_Hazarika](https://discourse.julialang.org/u/Ananya_Hazarika)\
**Replies:** 7\
**Last updated:** [January 9, 2024, 5:39am UTC](https://discourse.julialang.org/t/how-use-the-dependent-lags-part-in-solving-ddes/108246 "2024-01-09T05:39:19Z")
prob = DDEProblem(bc\_model, u0, h, tspan; dependent\_lags = ((u, p, t) → tau,)) alg = MethodOfSteps(Tsit5()) sol = solve(prob, alg) if i have lags that are random :within some range i.e ,i want to use random lags for e…
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## [UDEs & ModelingToolkit](https://discourse.julialang.org/t/udes-modelingtoolkit/108543)
**Author:** [@armansa](https://discourse.julialang.org/u/armansa)\
**Replies:** 1\
**Last updated:** [January 9, 2024, 3:48am UTC](https://discourse.julialang.org/t/udes-modelingtoolkit/108543 "2024-01-09T03:48:30Z")
Hi everyone, I’m using the UDE example here but trying to make it work for the case that my ODE system is not in defined in vector form (as it usually is for UODE examples I’ve seen), but in symbolic form using MTK. I h…
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## [Error precompiling on cluster](https://discourse.julialang.org/t/error-precompiling-on-cluster/104974)
**Author:** [@roi.holtzman](https://discourse.julialang.org/u/roi.holtzman)\
**Replies:** 26\
**Last updated:** [January 9, 2024, 2:14am UTC](https://discourse.julialang.org/t/error-precompiling-on-cluster/104974 "2024-01-09T02:14:09Z")
I am running a simple script on a cluster. I simply perform many instances of the same script. I get the following error: \\<94\>\<8C\> Warning: The call to compilecache failed to create a usable precompiled cache file …
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## [Propagate changes from git repo into package included with dev?](https://discourse.julialang.org/t/propagate-changes-from-git-repo-into-package-included-with-dev/108538)
**Author:** [@rkube](https://discourse.julialang.org/u/rkube)\
**Replies:** 2\
**Last updated:** [January 9, 2024, 2:05am UTC](https://discourse.julialang.org/t/propagate-changes-from-git-repo-into-package-included-with-dev/108538 "2024-01-09T02:05:19Z")
Hi, One of my environments has a package from a local git server in development mode checked out, added as pkg\> dev git@... After pushing modifications into the git repository, a function signature changed to pmt\_a…
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## [More, less, head, tail, to display arrays in REPL](https://discourse.julialang.org/t/more-less-head-tail-to-display-arrays-in-repl/47435)
**Author:** [@lmiq](https://discourse.julialang.org/u/lmiq)\
**Replies:** 23\
**Last updated:** [January 8, 2024, 11:54pm UTC](https://discourse.julialang.org/t/more-less-head-tail-to-display-arrays-in-repl/47435 "2024-01-08T23:54:04Z")
Is there any functionality which mimics the head, tail, more and less command in bash, but to visualize the contents of arrays? That would be quite useful, I think, for rapid inspection of data. Currently, the Base.disp…
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## [\[ANN\] SIAMFANLEquations.jl v1.0 Publication release](https://discourse.julialang.org/t/ann-siamfanlequations-jl-v1-0-publication-release/86946)
**Author:** [@ctkelley](https://discourse.julialang.org/u/ctkelley)\
**Replies:** 6\
**Last updated:** [January 8, 2024, 10:18pm UTC](https://discourse.julialang.org/t/ann-siamfanlequations-jl-v1-0-publication-release/86946 "2024-01-08T22:18:55Z")
La commedia è finita! This project is Done. I’ve just released v1.0, the final publication version, of SIAMFANLEquations.jl. This is a suite of nonlinear solvers, test problems, and examples. The solvers are Newton an…
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## [Why is \`Base.return\_types(String, Tuple{AbstractVector{UInt8}})\` so pessimistic for this method?](https://discourse.julialang.org/t/why-is-base-return-types-string-tuple-abstractvector-uint8-so-pessimistic-for-this-method/108505)
**Author:** [@nsajko](https://discourse.julialang.org/u/nsajko)\
**Replies:** 6\
**Last updated:** [January 8, 2024, 10:04pm UTC](https://discourse.julialang.org/t/why-is-base-return-types-string-tuple-abstractvector-uint8-so-pessimistic-for-this-method/108505 "2024-01-08T22:04:59Z")
julia\> Base.return\_types(String, Tuple{AbstractVector{UInt8}}) 3-element Vector{Any}: String String Any julia\> methods(String, Tuple{AbstractVector{UInt8}}) # 3 methods for type constructor: \[1\] String(v::Vector{UIn…
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## [How to plot a mirror graph from the one created](https://discourse.julialang.org/t/how-to-plot-a-mirror-graph-from-the-one-created/108394)
**Author:** [@kim1](https://discourse.julialang.org/u/kim1)\
**Replies:** 27\
**Last updated:** [January 8, 2024, 9:56pm UTC](https://discourse.julialang.org/t/how-to-plot-a-mirror-graph-from-the-one-created/108394 "2024-01-08T21:56:02Z")
Hi does anyone know how to plot my already plotted graph by mirroring it on the negative value?
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## [\`Pkg\` workflow after Julia version update](https://discourse.julialang.org/t/pkg-workflow-after-julia-version-update/108534)
**Author:** [@joaovgranja](https://discourse.julialang.org/u/joaovgranja)\
**Replies:** 6\
**Last updated:** [January 8, 2024, 9:20pm UTC](https://discourse.julialang.org/t/pkg-workflow-after-julia-version-update/108534 "2024-01-08T21:20:50Z")
I am on Ubuntu 22.04.03. I have installed Julia 1.10 using the curl command here. I want to update a project environment so that it uses Julia 1.10. However, upon activate . and instantiate, several packages fail to prec…
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## [Slow code/ high allocations on a Google Cloud VM](https://discourse.julialang.org/t/slow-code-high-allocations-on-a-google-cloud-vm/108535)
**Author:** [@Alb3r7](https://discourse.julialang.org/u/Alb3r7)\
**Replies:** 0\
**Last updated:** [January 8, 2024, 7:40pm UTC](https://discourse.julialang.org/t/slow-code-high-allocations-on-a-google-cloud-vm/108535 "2024-01-08T19:40:12Z")
Hello, I’m trying to run my Julia (1.9) code on an C3D Google Compute Engine, but I have unusual high allocations and a slow execution compared to my local machine: Has someone any experience on using a Google Cloud …
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## [Sources for the Zappa Nardelli et al. subtyping implementation?](https://discourse.julialang.org/t/sources-for-the-zappa-nardelli-et-al-subtyping-implementation/108531)
**Author:** [@nsajko](https://discourse.julialang.org/u/nsajko)\
**Replies:** 1\
**Last updated:** [January 8, 2024, 7:14pm UTC](https://discourse.julialang.org/t/sources-for-the-zappa-nardelli-et-al-subtyping-implementation/108531 "2024-01-08T19:14:26Z")
Francesco Zappa Nardelli, Julia Belyakova, Artem Pelenitsyn, Benjamin Chung, Jeff Bezanson, et al… Julia Subtyping: A Rational Reconstruction. Proceedings of the ACM on Programming Languages, 2018, 27, ⟨10.1145/3276483⟩…
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## [Column types in DataFrames](https://discourse.julialang.org/t/column-types-in-dataframes/108532)
**Author:** [@vsoler](https://discourse.julialang.org/u/vsoler)\
**Replies:** 3\
**Last updated:** [January 8, 2024, 7:14pm UTC](https://discourse.julialang.org/t/column-types-in-dataframes/108532 "2024-01-08T19:14:09Z")
I have a big DataFrame named df. I want to create, from it, another DataFrame with 2 columns: the first column should contain the column names of df. The second column should contain its column types. I have tried this…
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## [Memory Increase with DistributedArrays in Loop](https://discourse.julialang.org/t/memory-increase-with-distributedarrays-in-loop/108411)
**Author:** [@jcsyme](https://discourse.julialang.org/u/jcsyme)\
**Replies:** 2\
**Last updated:** [January 8, 2024, 7:08pm UTC](https://discourse.julialang.org/t/memory-increase-with-distributedarrays-in-loop/108411 "2024-01-08T19:08:23Z")
I’m working on parallelizing some graph algorithms, and I’m trying to use the DistributedArrays package to create an array that allows a worker to operate on a single vector without having to re-generate the array within…
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## [Install SSL/TLS Libraries in Julia?](https://discourse.julialang.org/t/install-ssl-tls-libraries-in-julia/108521)
**Author:** [@benslinux](https://discourse.julialang.org/u/benslinux)\
**Replies:** 4\
**Last updated:** [January 8, 2024, 6:38pm UTC](https://discourse.julialang.org/t/install-ssl-tls-libraries-in-julia/108521 "2024-01-08T18:38:56Z")
using HTTP using JSON function getIPInfo() url = "https://ipapi.co/json" response = HTTP.get(url) if response.status == 200 data = JSON.parse(String(response.body)) println("IP Information:"…
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## [Signature for \`jl\_array\_data\` is different in stable and nightly](https://discourse.julialang.org/t/signature-for-jl-array-data-is-different-in-stable-and-nightly/108519)
**Author:** [@dmitry-kabanov](https://discourse.julialang.org/u/dmitry-kabanov)\
**Replies:** 3\
**Last updated:** [January 8, 2024, 6:41pm UTC](https://discourse.julialang.org/t/signature-for-jl-array-data-is-different-in-stable-and-nightly/108519 "2024-01-08T18:41:32Z")
Hi, I have some C code with Julia embedding. The code is tested with versions 1.8 and nightly. However, it fails on nightly, due to the changes in the signature of jl\_array\_data (macro that obtains a C pointer from a Jul…
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## [Revise not updating functions](https://discourse.julialang.org/t/revise-not-updating-functions/108391)
**Author:** [@A\_C](https://discourse.julialang.org/u/A_C)\
**Replies:** 12\
**Last updated:** [January 8, 2024, 5:48pm UTC](https://discourse.julialang.org/t/revise-not-updating-functions/108391 "2024-01-08T17:48:06Z")
I am following the example here to redefine struct (by renaming it). But the function does not get recompiled with new type. I get the following error: julia\> MyPkg.processFoo(fs) ERROR: MethodError: no method matching …
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## [How to catch integrator problems](https://discourse.julialang.org/t/how-to-catch-integrator-problems/108512)
**Author:** [@Niall](https://discourse.julialang.org/u/Niall)\
**Replies:** 6\
**Last updated:** [January 8, 2024, 5:45pm UTC](https://discourse.julialang.org/t/how-to-catch-integrator-problems/108512 "2024-01-08T17:45:59Z")
I am using a CoupledODEs as a test for the results of a genetic algorithm. In other words, the parameter values (here 0.5 and 1.8) are chosen at random by the GA, then tested by solving the ODEs. This means that occasion…
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## [What does @inline mean?](https://discourse.julialang.org/t/what-does-inline-mean/108516)
**Author:** [@jiang\_ming\_zhang](https://discourse.julialang.org/u/jiang_ming_zhang)\
**Replies:** 4\
**Last updated:** [January 8, 2024, 4:27pm UTC](https://discourse.julialang.org/t/what-does-inline-mean/108516 "2024-01-08T16:27:09Z")
I see a lot of “@inline function” in a package. What does it mean? According to https://subscription.packtpub.com/book/programming/9781785880919/4/ch04lvl1sec23/inlining, it is just a way to avoid the function call overh…
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## [Precompilation issue with DifferentialEquations.jl](https://discourse.julialang.org/t/precompilation-issue-with-differentialequations-jl/108517)
**Author:** [@sandeeptegar](https://discourse.julialang.org/u/sandeeptegar)\
**Replies:** 16\
**Last updated:** [January 8, 2024, 4:25pm UTC](https://discourse.julialang.org/t/precompilation-issue-with-differentialequations-jl/108517 "2024-01-08T16:25:39Z")
I am using julia-1.10.0. I am using julia remotely on the Rocky 9 VM. I am getting the following error in the pre-compilation of the DifferentialEquations.jl package: PkgPrecompileError: The following 1 direct depende…
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## [Normalization of eigenvectors in Arpack](https://discourse.julialang.org/t/normalization-of-eigenvectors-in-arpack/108492)
**Author:** [@PetrKryslUCSD](https://discourse.julialang.org/u/PetrKryslUCSD)\
**Replies:** 3\
**Last updated:** [January 8, 2024, 4:22pm UTC](https://discourse.julialang.org/t/normalization-of-eigenvectors-in-arpack/108492 "2024-01-08T16:22:09Z")
I call eigs from two separate packages. In the first, eigs returns vectors normalized to unit length, in the second they are normalized relative to the second matrix in the pencil (mass). Obviously, both matrix pencils …
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## [Tuple of Tuple to Tuple](https://discourse.julialang.org/t/tuple-of-tuple-to-tuple/108447)
**Author:** [@scelles](https://discourse.julialang.org/u/scelles)\
**Replies:** 9\
**Last updated:** [January 8, 2024, 4:18pm UTC](https://discourse.julialang.org/t/tuple-of-tuple-to-tuple/108447 "2024-01-08T16:18:58Z")
Hello, I have 2 variables like julia\> a = 1:5 1:5 julia\> b = \[("a", 10), ("b", 20), ("c", 30), ("d", 40) , ("e", 50)\] 5-element Vector{Tuple{String, Int64}}: ("a", 10) ("b", 20) ("c", 30) ("d", 40) ("e", 50) Whe…
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## [How to set the same uniform units for all axes in 3D surface plot using Plots.jl?](https://discourse.julialang.org/t/how-to-set-the-same-uniform-units-for-all-axes-in-3d-surface-plot-using-plots-jl/108510)
**Author:** [@homocomputeris](https://discourse.julialang.org/u/homocomputeris)\
**Replies:** 3\
**Last updated:** [January 8, 2024, 3:10pm UTC](https://discourse.julialang.org/t/how-to-set-the-same-uniform-units-for-all-axes-in-3d-surface-plot-using-plots-jl/108510 "2024-01-08T15:10:32Z")
I want to have a “normal” plot where all axes are the same, without any scaling, i.e. the length in every axis is the same. surface(xs, ts, f; fillalpha=0.9, camera=(20, 40), aspect\_ratio=1) gives this where 1 in the z…
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## [Kate Gregory “Naming is Hard: Let's Do Better” and what lesson we can learn from it](https://discourse.julialang.org/t/kate-gregory-naming-is-hard-lets-do-better-and-what-lesson-we-can-learn-from-it/108216)
**Author:** [@KZiemian](https://discourse.julialang.org/u/KZiemian)\
**Replies:** 34\
**Last updated:** [January 8, 2024, 1:48pm UTC](https://discourse.julialang.org/t/kate-gregory-naming-is-hard-lets-do-better-and-what-lesson-we-can-learn-from-it/108216 "2024-01-08T13:48:58Z")
Kate Greogry talk Naming is Hard: Let’s Do Better is not specific about C++, Julia or any other language, but how to name things properly in any language. As currently working as teacher and leading exercise classes of i…
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## [How to delete a function?](https://discourse.julialang.org/t/how-to-delete-a-function/108422)
**Author:** [@jiang\_ming\_zhang](https://discourse.julialang.org/u/jiang_ming_zhang)\
**Replies:** 7\
**Last updated:** [January 8, 2024, 1:47pm UTC](https://discourse.julialang.org/t/how-to-delete-a-function/108422 "2024-01-08T13:47:15Z")
I want to experiment with a small function. Before defining it, I want to make sure that the function name is not used before, or it does not exist in the workspace. How can I do it? In Matlab, it is simple with ‘clear’ …
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## [XGBoostClassifier on bigger than RAM database](https://discourse.julialang.org/t/xgboostclassifier-on-bigger-than-ram-database/108358)
**Author:** [@Paulo\_Refosco](https://discourse.julialang.org/u/Paulo_Refosco)\
**Replies:** 2\
**Last updated:** [January 8, 2024, 12:56pm UTC](https://discourse.julialang.org/t/xgboostclassifier-on-bigger-than-ram-database/108358 "2024-01-08T12:56:13Z")
Hello, I am trying to run XGBoostClassifier on a dataset that doesn’t fit into RAM, so getting OutOfMemoryError(). I’m not soo much proeficient on writing codes but I think solutions could range from mini-batches and/or…
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## [How to plot a line in 3D using Plots.jl?](https://discourse.julialang.org/t/how-to-plot-a-line-in-3d-using-plots-jl/108267)
**Author:** [@homocomputeris](https://discourse.julialang.org/u/homocomputeris)\
**Replies:** 8\
**Last updated:** [January 8, 2024, 12:15pm UTC](https://discourse.julialang.org/t/how-to-plot-a-line-in-3d-using-plots-jl/108267 "2024-01-08T12:15:54Z")
How to plot a line in a 3D axis? Say, I want a parabola in the xy-plane (z=0) The straightforward options do not work; This one results an empty canvas \[-1, 1\] x \[-1, 1\]: using Plots xs = -5:1:5 plot(xs, xs.^2, 0) T…
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## [Fieldnames for user-defined structs](https://discourse.julialang.org/t/fieldnames-for-user-defined-structs/108508)
**Author:** [@jiang\_ming\_zhang](https://discourse.julialang.org/u/jiang_ming_zhang)\
**Replies:** 4\
**Last updated:** [January 8, 2024, 11:51am UTC](https://discourse.julialang.org/t/fieldnames-for-user-defined-structs/108508 "2024-01-08T11:51:35Z")
julia\> struct Foo bar baz::Int qux::Float64 end julia\> foo = Foo(1,2,3) Foo(1, 2, 3.0) julia\> fieldnames(foo) ERROR: MethodError: no method matching fieldnam…
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## [IOError: could not spawn node.exe and vl2vg.js](https://discourse.julialang.org/t/ioerror-could-not-spawn-node-exe-and-vl2vg-js/108509)
**Author:** [@desanti58](https://discourse.julialang.org/u/desanti58)\
**Replies:** 0\
**Last updated:** [January 8, 2024, 11:22am UTC](https://discourse.julialang.org/t/ioerror-could-not-spawn-node-exe-and-vl2vg-js/108509 "2024-01-08T11:22:19Z")
Hello, I am trying to save a VegaLite plot as a SVG format. However, I get the following error: IOError: could not spawn setenv(\`'C:\\Users\\u0152683\\.julia\\artifacts\\0bd56198ac47b98572257a7725d9425f5a1ba1a9\\node.exe' 'C…
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## [How to create task firstly and start it not on the main thread?](https://discourse.julialang.org/t/how-to-create-task-firstly-and-start-it-not-on-the-main-thread/108502)
**Author:** [@SunnyUser](https://discourse.julialang.org/u/SunnyUser)\
**Replies:** 2\
**Last updated:** [January 8, 2024, 9:34am UTC](https://discourse.julialang.org/t/how-to-create-task-firstly-and-start-it-not-on-the-main-thread/108502 "2024-01-08T09:34:34Z")
Hi all :slight\_smile: I want to seperate task creation and task start, but I want to use all available threads. Thanks
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