# Latest

**URL:** https://discourse.julialang.org/latest.md?page=978

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

**Page:** 979

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## [\[WIP\] SimpleLazyGraphs.jl - add vertices and edges as needed](https://discourse.julialang.org/t/wip-simplelazygraphs-jl-add-vertices-and-edges-as-needed/84326)

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**Author:** [@acxz](https://discourse.julialang.org/u/acxz)\
**Replies:** 6\
**Last updated:** [July 18, 2022, 2:37pm UTC](https://discourse.julialang.org/t/wip-simplelazygraphs-jl-add-vertices-and-edges-as-needed/84326 "2022-07-18T14:37:48Z")

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Hello all, I’d like to introduce a small module I’ve been trying to implement called SimpleLazyGraphs.jl: GitHub - acxz/SimpleLazyGraphs.jl: Graph data structures to add vertices and edges as needed for Graphs.jl. Effec…

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## [PhD position on scientific ML of soil organic carbon in Germany](https://discourse.julialang.org/t/phd-position-on-scientific-ml-of-soil-organic-carbon-in-germany/84411)

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**Author:** [@BernhardAhrens](https://discourse.julialang.org/u/BernhardAhrens)\
**Replies:** 0\
**Last updated:** [July 18, 2022, 3:36pm UTC](https://discourse.julialang.org/t/phd-position-on-scientific-ml-of-soil-organic-carbon-in-germany/84411 "2022-07-18T15:36:33Z")

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Hey everyone who is interested in scientific machine learning! At the Max Planck Institute for Biogeochemistry in Jena, Germany, we offer a PhD position that will use the SciML ecosystem to combine ‘process-based and de…

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## [Indenting code](https://discourse.julialang.org/t/indenting-code/84405)

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**Author:** [@f.ij](https://discourse.julialang.org/u/f.ij)\
**Replies:** 4\
**Last updated:** [July 18, 2022, 2:38pm UTC](https://discourse.julialang.org/t/indenting-code/84405 "2022-07-18T14:38:57Z")

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Hi, I was wondering how I can indent code if I type it directly into the forum textfield.

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## [Issues reading big CSV file despite using CSV.Row](https://discourse.julialang.org/t/issues-reading-big-csv-file-despite-using-csv-row/84395)

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**Author:** [@candidaorelmex](https://discourse.julialang.org/u/candidaorelmex)\
**Replies:** 14\
**Last updated:** [July 18, 2022, 1:48pm UTC](https://discourse.julialang.org/t/issues-reading-big-csv-file-despite-using-csv-row/84395 "2022-07-18T13:48:11Z")

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I’d like to import a .tsv file which CSV.read(file, DataFrame) doesn’t like. The error I get is ArgumentError: length argument to Parsers.PosLen (204996615) is too large; max length allowed is 1048575 I found an alt…

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## [Overlaying single value on a histogram](https://discourse.julialang.org/t/overlaying-single-value-on-a-histogram/84393)

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**Author:** [@AnshPatel7](https://discourse.julialang.org/u/AnshPatel7)\
**Replies:** 2\
**Last updated:** [July 18, 2022, 1:48pm UTC](https://discourse.julialang.org/t/overlaying-single-value-on-a-histogram/84393 "2022-07-18T13:48:43Z")

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Hi, I’m using the hist function in the CairoMakie package to create a layout of histograms. The histograms show the distribution of means from bootstrapping. I also have the theoretical mean values which I would like to…

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## [\[ANN\] Announcing Jl2Py.jl: A minimal Julia-to-Python transpiler](https://discourse.julialang.org/t/ann-announcing-jl2py-jl-a-minimal-julia-to-python-transpiler/84406)

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**Author:** [@lucifer1004](https://discourse.julialang.org/u/lucifer1004)\
**Replies:** 0\
**Last updated:** [July 18, 2022, 1:33pm UTC](https://discourse.julialang.org/t/ann-announcing-jl2py-jl-a-minimal-julia-to-python-transpiler/84406 "2022-07-18T13:33:06Z")

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Jl2Py.jl is a minimal package (roughly 400 LOC at the moment) that transpiles Julia code to Python. Example (from LeetCode.jl): function two\_sum(nums::Vector{Int}, target::Int)::Union{Nothing,Tuple{Int,Int}} seen =…

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## [Julia alternatives or interface for ACADO for NMPC?](https://discourse.julialang.org/t/julia-alternatives-or-interface-for-acado-for-nmpc/84401)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 0\
**Last updated:** [July 18, 2022, 12:04pm UTC](https://discourse.julialang.org/t/julia-alternatives-or-interface-for-acado-for-nmpc/84401 "2022-07-18T12:04:17Z")

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There is a MATLAB interface/ wrapper for the ACADO C++ library, see: Features Would it make sense to create a wrapper in Julia? Or would it be better to implement this functionality (non-linear optimal control, non-lin…

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## [Kmeans clustering using Clustering package](https://discourse.julialang.org/t/kmeans-clustering-using-clustering-package/84391)

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**Author:** [@Shayan](https://discourse.julialang.org/u/Shayan)\
**Replies:** 2\
**Last updated:** [July 18, 2022, 12:06pm UTC](https://discourse.julialang.org/t/kmeans-clustering-using-clustering-package/84391 "2022-07-18T12:06:42Z")

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The documentation of kmeans of the Clustering.jl states that: help?\> kmeans search: kmeans kmeans! kmeans\_opts KmeansResult kmeans(X, k, \[...\]) -\> KmeansResult K-means clustering of the d×n data matrix X (each co…

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## [Clustering.jl Silhouettes Distances](https://discourse.julialang.org/t/clustering-jl-silhouettes-distances/33810)

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**Author:** [@mthelm85](https://discourse.julialang.org/u/mthelm85)\
**Replies:** 8\
**Last updated:** [July 18, 2022, 11:04am UTC](https://discourse.julialang.org/t/clustering-jl-silhouettes-distances/33810 "2022-07-18T11:04:03Z")

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The docs state: Note that si≤1, and that si is close to 1 when the i-th point lies well within its own cluster. This property allows using mean(silhouettes(assignments, counts, X)) as a measure of clustering quality. H…

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## [UDE giving Linear Approximation](https://discourse.julialang.org/t/ude-giving-linear-approximation/84327)

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**Author:** [@ccccc](https://discourse.julialang.org/u/ccccc)\
**Replies:** 4\
**Last updated:** [July 18, 2022, 10:40am UTC](https://discourse.julialang.org/t/ude-giving-linear-approximation/84327 "2022-07-18T10:40:49Z")

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I copied the example here: And put in my own function. Everything else is the same except for I didn’t add noise. U = Lux.Chain( Lux.Dense(5,3,rbf), Lux.Dense(3,3, rbf), Lux.Dense(3,3, rbf), Lux.Dense(3,5) ) # Get…

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## [Search nested namedtuples by key](https://discourse.julialang.org/t/search-nested-namedtuples-by-key/84352)

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**Author:** [@rocco\_sprmnt21](https://discourse.julialang.org/u/rocco_sprmnt21)\
**Replies:** 5\
**Last updated:** [July 18, 2022, 10:15am UTC](https://discourse.julialang.org/t/search-nested-namedtuples-by-key/84352 "2022-07-18T10:15:09Z")

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using the Functor package I quickly found how to search by value type, but not by key. Is it possible to do this (ie search by key) in some way or with the help of another package? julia\> nt=(gr='a',f1=1, f2=(gr='b', f…

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## [Poll: Do you use convenience functions such as \`zeros\` to construct OffsetArrays?](https://discourse.julialang.org/t/poll-do-you-use-convenience-functions-such-as-zeros-to-construct-offsetarrays/84377)

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**Author:** [@jishnub](https://discourse.julialang.org/u/jishnub)\
**Replies:** 4\
**Last updated:** [July 18, 2022, 8:59am UTC](https://discourse.julialang.org/t/poll-do-you-use-convenience-functions-such-as-zeros-to-construct-offsetarrays/84377 "2022-07-18T08:59:34Z")

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Recently, it has been pointed out that the type-piracy committed by OffsetArrays can lead to unexpected results. In particular, OffsetArrays provides the convenience method zeros(::Union{Integer, AbstractUnitRange}...) t…

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## [On-the-fly plotting in a script](https://discourse.julialang.org/t/on-the-fly-plotting-in-a-script/84390)

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**Author:** [@Nathaniel](https://discourse.julialang.org/u/Nathaniel)\
**Replies:** 2\
**Last updated:** [July 18, 2022, 9:46am UTC](https://discourse.julialang.org/t/on-the-fly-plotting-in-a-script/84390 "2022-07-18T09:46:53Z")

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I am writing a julia script and would like to do the following: open a plot window run a few steps of my model update the plot window to show the current status of the model repeat steps 2 and 3 indefinitely I found a…

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## [Rename files in a directory](https://discourse.julialang.org/t/rename-files-in-a-directory/84389)

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**Author:** [@Nash](https://discourse.julialang.org/u/Nash)\
**Replies:** 2\
**Last updated:** [July 18, 2022, 9:26am UTC](https://discourse.julialang.org/t/rename-files-in-a-directory/84389 "2022-07-18T09:26:13Z")

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In my directory, I have many files whose names all include the string “May\_2022”. For example “Bob\_May\_2022”. I want to change the name of every file so that the part “May\_2022” is replaced by “05\_22”. For example to “Bo…

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## [Slope at a point of RNN using Flux](https://discourse.julialang.org/t/slope-at-a-point-of-rnn-using-flux/84207)

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**Author:** [@FrootLoops](https://discourse.julialang.org/u/FrootLoops)\
**Replies:** 1\
**Last updated:** [July 18, 2022, 8:47am UTC](https://discourse.julialang.org/t/slope-at-a-point-of-rnn-using-flux/84207 "2022-07-18T08:47:04Z")

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I am using a recurrent neural network for data of the form (x\_t, y\_t)\_{t=1}^T. My RNN has therefore the form y\_t^{nn} = NN(x\_{t-1}, x\_t, y\_{t-1}), with 1 hidden layer, 20 neurons, a sigmoid activation function and a li…

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## [How do I obtain \`sizeof(struct sigaction)\`? Clang.jl?](https://discourse.julialang.org/t/how-do-i-obtain-sizeof-struct-sigaction-clang-jl/84344)

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**Author:** [@mkitti](https://discourse.julialang.org/u/mkitti)\
**Replies:** 4\
**Last updated:** [July 18, 2022, 8:33am UTC](https://discourse.julialang.org/t/how-do-i-obtain-sizeof-struct-sigaction-clang-jl/84344 "2022-07-18T08:33:42Z")

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I would like to figure out the value printed by this C program in Julia. #include \<signal.h\> #include \<stdio.h\> int main() { printf("%ld", sizeof(struct sigaction)); return 0; } On my system, this print…

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## [Combine two strings and put in seperate line as single strings](https://discourse.julialang.org/t/combine-two-strings-and-put-in-seperate-line-as-single-strings/84370)

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**Author:** [@ayodyas](https://discourse.julialang.org/u/ayodyas)\
**Replies:** 3\
**Last updated:** [July 18, 2022, 8:02am UTC](https://discourse.julialang.org/t/combine-two-strings-and-put-in-seperate-line-as-single-strings/84370 "2022-07-18T08:02:03Z")

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I have a=‘light’, b=‘switch’, I combined a and b using c=a\*b and got 'lightswitch but I need c= light switch purpose is to node labeling, where the size is limited

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## [\[ANN\] Nonconvex 2.1 - more algorithms, documentation and autodiff features](https://discourse.julialang.org/t/ann-nonconvex-2-1-more-algorithms-documentation-and-autodiff-features/84264)

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**Author:** [@mohamed82008](https://discourse.julialang.org/u/mohamed82008)\
**Replies:** 5\
**Last updated:** [July 18, 2022, 8:00am UTC](https://discourse.julialang.org/t/ann-nonconvex-2-1-more-algorithms-documentation-and-autodiff-features/84264 "2022-07-18T08:00:56Z")

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I have been slowly adding features and documentation to Nonconvex.jl and the JuliaNonconvex organization at large and it’s time to make a new announcement. Here are some updates with the new version. The README and do…

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## [Macro names](https://discourse.julialang.org/t/macro-names/84378)

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**Author:** [@Lincoln\_Hannah](https://discourse.julialang.org/u/Lincoln_Hannah)\
**Replies:** 1\
**Last updated:** [July 18, 2022, 7:14am UTC](https://discourse.julialang.org/t/macro-names/84378 "2022-07-18T07:14:45Z")

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using DataFrames, DataFramesMeta, DataFrameMacros using the above packages I have to preface some macro names with the package name. I presume this is because the same macro exists in multiple packages. Is there a way…

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## [Graphs.jl : UndefVarError: nv not defined](https://discourse.julialang.org/t/graphs-jl-undefvarerror-nv-not-defined/84381)

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**Author:** [@Freya\_the\_Goddess](https://discourse.julialang.org/u/Freya_the_Goddess)\
**Replies:** 0\
**Last updated:** [July 18, 2022, 7:04am UTC](https://discourse.julialang.org/t/graphs-jl-undefvarerror-nv-not-defined/84381 "2022-07-18T07:04:30Z")

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Hi all, I am using Jupyter Notebook on this tutorial https://pszufe.github.io/OpenStreetMapX\_Tutorial/JuliaCon2021/ I change LightGraphs into Graphs. Then there is an error when running this code: m = get\_map\_data("/…

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## [How to implment \`logsumexp\` function in JuMP?](https://discourse.julialang.org/t/how-to-implment-logsumexp-function-in-jump/84376)

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**Author:** [@iHany](https://discourse.julialang.org/u/iHany)\
**Replies:** 7\
**Last updated:** [July 18, 2022, 6:23am UTC](https://discourse.julialang.org/t/how-to-implment-logsumexp-function-in-jump/84376 "2022-07-18T06:23:24Z")

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Hi, as I described my situation here, I’m trying to use DiffOpt.jl for my custom neural network training. I realised that if I can use logsumexp function to express the objective function, I can make it. However, I ca…

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## [MLJ and DiffEqFlux](https://discourse.julialang.org/t/mlj-and-diffeqflux/84259)

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**Author:** [@bienpierre](https://discourse.julialang.org/u/bienpierre)\
**Replies:** 1\
**Last updated:** [July 18, 2022, 4:02am UTC](https://discourse.julialang.org/t/mlj-and-diffeqflux/84259 "2022-07-18T04:02:55Z")

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Hello everyone, I would like to know if it is possible to use MLJFlux with DiffEqFlux, or does it exist a interface? Do I have to add method, such as: fit!(loss, penalty, chain::Something\_related\_to\_DiffEqFlux, optimi…

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## [Syntax for specifying block diagonal constraints in Convex](https://discourse.julialang.org/t/syntax-for-specifying-block-diagonal-constraints-in-convex/84372)

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**Author:** [@biona001](https://discourse.julialang.org/u/biona001)\
**Replies:** 5\
**Last updated:** [July 18, 2022, 4:01am UTC](https://discourse.julialang.org/t/syntax-for-specifying-block-diagonal-constraints-in-convex/84372 "2022-07-18T04:01:41Z")

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Hi community, I am having issues inputting the following problem into Convex.jl where \\Sigma and S\_1,...,S\_m are positive definite matrices of appropriate dimensions. The syntax diag(x\_1S\_1,...,x\_mS\_m) in the constrai…

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## [ReverseDiff - differentiating with respect to some parameters but not others](https://discourse.julialang.org/t/reversediff-differentiating-with-respect-to-some-parameters-but-not-others/84345)

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**Author:** [@Nathaniel](https://discourse.julialang.org/u/Nathaniel)\
**Replies:** 6\
**Last updated:** [July 18, 2022, 3:42am UTC](https://discourse.julialang.org/t/reversediff-differentiating-with-respect-to-some-parameters-but-not-others/84345 "2022-07-18T03:42:50Z")

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I’m planning on training some neural networks using ReverseDiff.jl (which I think makes sense because I’ll be training lots of small networks on the CPU), but I have a basic question about how ReverseDiff is intended to …

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## [Repetition of sample blocks the building of Kriging surrogate model](https://discourse.julialang.org/t/repetition-of-sample-blocks-the-building-of-kriging-surrogate-model/84374)

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**Author:** [@chenr86](https://discourse.julialang.org/u/chenr86)\
**Replies:** 1\
**Last updated:** [July 18, 2022, 2:40am UTC](https://discourse.julialang.org/t/repetition-of-sample-blocks-the-building-of-kriging-surrogate-model/84374 "2022-07-18T02:40:14Z")

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Hello, I’m using my own data as input to build a kriging model. There are three columns for input variables, one column for output variable. For input, there are: day\_of\_year: transforming the date into the day of ye…

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## [Announcing my first Julia package, 'HypergeoMat'](https://discourse.julialang.org/t/announcing-my-first-julia-package-hypergeomat/51751)

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**Author:** [@stla](https://discourse.julialang.org/u/stla)\
**Replies:** 12\
**Last updated:** [July 18, 2022, 1:09am UTC](https://discourse.julialang.org/t/announcing-my-first-julia-package-hypergeomat/51751 "2022-07-18T01:09:09Z")

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Hello, Just to announce my first Julia package. Cheers.

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## [Nothing/nothing location](https://discourse.julialang.org/t/nothing-nothing-location/84363)

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**Author:** [@kurt](https://discourse.julialang.org/u/kurt)\
**Replies:** 5\
**Last updated:** [July 18, 2022, 1:08am UTC](https://discourse.julialang.org/t/nothing-nothing-location/84363 "2022-07-18T01:08:35Z")

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Please, where is Nothing/nothing declared? Thank you ahead of time.

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## [Specifying model with threshold / ifelse likelihood in Turing / Soss / Tilde](https://discourse.julialang.org/t/specifying-model-with-threshold-ifelse-likelihood-in-turing-soss-tilde/83473)

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**Author:** [@Jakob](https://discourse.julialang.org/u/Jakob)\
**Replies:** 5\
**Last updated:** [July 17, 2022, 8:31pm UTC](https://discourse.julialang.org/t/specifying-model-with-threshold-ifelse-likelihood-in-turing-soss-tilde/83473 "2022-07-17T20:31:20Z")

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Hi everyone, I have a model which is a simplified version of the one presented in Mulder & Hoff (2021) and looks something like this: \\begin{align} \\mathbf{z}\_{i} &\\sim \\textrm{MvNormal}(\\boldsymbol{\\theta}\_{i},\\math…

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## [Dealing with external libraries that don't restore old signal handlers](https://discourse.julialang.org/t/dealing-with-external-libraries-that-dont-restore-old-signal-handlers/84343)

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**Author:** [@sobhan](https://discourse.julialang.org/u/sobhan)\
**Replies:** 7\
**Last updated:** [July 17, 2022, 5:54pm UTC](https://discourse.julialang.org/t/dealing-with-external-libraries-that-dont-restore-old-signal-handlers/84343 "2022-07-17T17:54:03Z")

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TLDR: if the code is segfaulting outside Ccalls AFTER Ccalls in threaded GC, it might be that the C library has loaded a custom signal handler and is competing with julia’s handler. The solution is something like """ s…

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## [Vectorized gradient using ForwardDiff](https://discourse.julialang.org/t/vectorized-gradient-using-forwarddiff/84315)

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**Author:** [@Vik1](https://discourse.julialang.org/u/Vik1)\
**Replies:** 5\
**Last updated:** [July 17, 2022, 5:45pm UTC](https://discourse.julialang.org/t/vectorized-gradient-using-forwarddiff/84315 "2022-07-17T17:45:22Z")

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Hi and greetings :slight\_smile: I am trying to compute derivatives (later on up to the 3rd or 4th degree) of vectorized functions using ForwardDiff. The functions are generally in the following form: using BenchmarkToo…

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