# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1048

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

**Page:** 1049

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## [TORA: Invalid number in NLP function or derivative detected](https://discourse.julialang.org/t/tora-invalid-number-in-nlp-function-or-derivative-detected/80511)

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**Author:** [@hedonismbot](https://discourse.julialang.org/u/hedonismbot)\
**Replies:** 6\
**Last updated:** [May 6, 2022, 1:45pm UTC](https://discourse.julialang.org/t/tora-invalid-number-in-nlp-function-or-derivative-detected/80511 "2022-05-06T13:45:14Z")

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On a custom URDF file (fanuc.urdf · GitHub), the tutorial for tora.jl (Tutorial · TORA.jl) always fails with this error: EXIT: Invalid number in NLP function or derivative detected. (6.328051371, \[0.0, 0.0, 0.0, 0.0, …

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## [Learning to Rank?](https://discourse.julialang.org/t/learning-to-rank/80527)

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**Author:** [@Billpete002](https://discourse.julialang.org/u/Billpete002)\
**Replies:** 8\
**Last updated:** [May 6, 2022, 1:30pm UTC](https://discourse.julialang.org/t/learning-to-rank/80527 "2022-05-06T13:30:44Z")

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Hi, I am wondering if there is any package which has a 100% Julia “learning to rank” feature besides XGBoost.jl? (my dataset would be too wide if I did that). I have checked MLRanking.jl but this is deprecated by 6 year…

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## [I want to make an hospital emergency department model](https://discourse.julialang.org/t/i-want-to-make-an-hospital-emergency-department-model/80608)

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**Author:** [@Floyd\_Gartner](https://discourse.julialang.org/u/Floyd_Gartner)\
**Replies:** 2\
**Last updated:** [May 6, 2022, 1:06pm UTC](https://discourse.julialang.org/t/i-want-to-make-an-hospital-emergency-department-model/80608 "2022-05-06T13:06:30Z")

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Hi everybody, I’m super new to Julia and still don’t know how to get started. I want to make a model that simulates an emergency department in a hospital. More specifically I want to show the patient assignment to free…

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## [How to make a model applicable to Turing.jl?](https://discourse.julialang.org/t/how-to-make-a-model-applicable-to-turing-jl/80561)

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**Author:** [@RPS](https://discourse.julialang.org/u/RPS)\
**Replies:** 2\
**Last updated:** [May 6, 2022, 1:04pm UTC](https://discourse.julialang.org/t/how-to-make-a-model-applicable-to-turing-jl/80561 "2022-05-06T13:04:40Z")

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I’ve implemented a model, for which I would like to use Turing.jl to evaluate the posterior distribution of the model parameters. The problem I’m facing is that the way I’m storing the model parameters (around 20-40, dep…

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## [3 PhD Positions on: Deep Learning on data cubes for answering question on Earth system dynamics](https://discourse.julialang.org/t/3-phd-positions-on-deep-learning-on-data-cubes-for-answering-question-on-earth-system-dynamics/55183)

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**Author:** [@mafla](https://discourse.julialang.org/u/mafla)\
**Replies:** 11\
**Last updated:** [May 6, 2022, 12:36pm UTC](https://discourse.julialang.org/t/3-phd-positions-on-deep-learning-on-data-cubes-for-answering-question-on-earth-system-dynamics/55183 "2022-05-06T12:36:37Z")

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Dear Julia GEO community, we have three PhD Positions (m/f/x) available at the newly established Remote Sensing Centre for Earth System Research (RSC4Earth) in Leipzig, Germany on Deep Learning for Vegetation Paramete…

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## [\[ANN\] Pathfinder.jl: speeding up the Bayesian workflow](https://discourse.julialang.org/t/ann-pathfinder-jl-speeding-up-the-bayesian-workflow/80464)

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**Author:** [@sethaxen](https://discourse.julialang.org/u/sethaxen)\
**Replies:** 15\
**Last updated:** [May 6, 2022, 12:35pm UTC](https://discourse.julialang.org/t/ann-pathfinder-jl-speeding-up-the-bayesian-workflow/80464 "2022-05-06T12:35:34Z")

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Pathfinder is a variational method designed to replace some or all phases of the warm-up phase of Markov Chain Monte Carlo. Its draws can also be used to diagnose problems with Bayesian models early in a model developmen…

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## [Stacked bars for different length](https://discourse.julialang.org/t/stacked-bars-for-different-length/80577)

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**Author:** [@Aminath\_Shausan](https://discourse.julialang.org/u/Aminath_Shausan)\
**Replies:** 2\
**Last updated:** [May 6, 2022, 12:07pm UTC](https://discourse.julialang.org/t/stacked-bars-for-different-length/80577 "2022-05-06T12:07:08Z")

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Hi, I am trying to plot stacked bar graphs from the following data frame: name duration label String3 Int64 SubStri… 1 AUS 31 1 2 AUS 89 2 3 AUS 133 3 4 GBR 86 1 5 GBR 88 …

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## [\[Makie\] Help with plotting just the boundary of a polygon](https://discourse.julialang.org/t/makie-help-with-plotting-just-the-boundary-of-a-polygon/80556)

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**Author:** [@Pappy](https://discourse.julialang.org/u/Pappy)\
**Replies:** 6\
**Last updated:** [May 6, 2022, 11:39am UTC](https://discourse.julialang.org/t/makie-help-with-plotting-just-the-boundary-of-a-polygon/80556 "2022-05-06T11:39:25Z")

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Hi, I am using makie to plot some shapes. Is there any way to plot just the boundary? The poly function works the exact way I want, but it doesn’t appear to have an arguement that allows you to just plot the boundary of …

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## [Optimizing a Spectral Proper Orthogonal Decomposition Method](https://discourse.julialang.org/t/optimizing-a-spectral-proper-orthogonal-decomposition-method/80522)

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**Author:** [@Whyborn](https://discourse.julialang.org/u/Whyborn)\
**Replies:** 19\
**Last updated:** [May 6, 2022, 11:24am UTC](https://discourse.julialang.org/t/optimizing-a-spectral-proper-orthogonal-decomposition-method/80522 "2022-05-06T11:24:45Z")

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I have written a Spectral Proper Orthogonal Decomposition (doi:10.1017/jfm.2018.283) algorithm in both Python and Julia, and I’ve found my Python code to be about 5x faster than the Julia code. I expect the performance t…

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## [Luxor.jl - resize canvas?](https://discourse.julialang.org/t/luxor-jl-resize-canvas/80603)

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**Author:** [@MLackner](https://discourse.julialang.org/u/MLackner)\
**Replies:** 1\
**Last updated:** [May 6, 2022, 11:22am UTC](https://discourse.julialang.org/t/luxor-jl-resize-canvas/80603 "2022-05-06T11:22:43Z")

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Is there a way to resize a canvas in Luxor.jl so it includes the bounding boxes of all elements? Suppose I have the following code generating a drawing: @png begin circle(Point(200, 200), 150, :fill) end Now the cir…

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## [Line flow contrainit in DC optimal powerflow](https://discourse.julialang.org/t/line-flow-contrainit-in-dc-optimal-powerflow/80389)

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**Author:** [@ayodyas](https://discourse.julialang.org/u/ayodyas)\
**Replies:** 2\
**Last updated:** [May 6, 2022, 10:29am UTC](https://discourse.julialang.org/t/line-flow-contrainit-in-dc-optimal-powerflow/80389 "2022-05-06T10:29:50Z")

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Is there any powerflow package in julia to determine the line flow limit in DC-Optimal Powerflow according to the equation Pmax\_line \<= PTDF(PG - PD) \<= Pmax\_line

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## [A problem about JUMP function fix](https://discourse.julialang.org/t/a-problem-about-jump-function-fix/80596)

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**Author:** [@mahon](https://discourse.julialang.org/u/mahon)\
**Replies:** 2\
**Last updated:** [May 6, 2022, 10:08am UTC](https://discourse.julialang.org/t/a-problem-about-jump-function-fix/80596 "2022-05-06T10:08:13Z")

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Hello , i am trying to use function fix to fix a matrix variable for example @variable(model, P\_dch\[1:2,1:2\]); fix(P\_dch, \[0 0;0 0\]); but it doesn\`t work, how can i do ? thanks

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## [Performance of global variables as default argument values](https://discourse.julialang.org/t/performance-of-global-variables-as-default-argument-values/80399)

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**Author:** [@jbu](https://discourse.julialang.org/u/jbu)\
**Replies:** 8\
**Last updated:** [May 6, 2022, 8:54am UTC](https://discourse.julialang.org/t/performance-of-global-variables-as-default-argument-values/80399 "2022-05-06T08:54:11Z")

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Is there a performance penalty for using non-const global variables as default argument values in functions? For example, consider the following snippet: globalval = 10 function addxy(x, y=globalval) return x + y e…

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## [Display numerical data](https://discourse.julialang.org/t/display-numerical-data/80589)

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**Author:** [@sransome](https://discourse.julialang.org/u/sransome)\
**Replies:** 2\
**Last updated:** [May 6, 2022, 6:23am UTC](https://discourse.julialang.org/t/display-numerical-data/80589 "2022-05-06T06:23:16Z")

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Now that I’m comfortable with displaying the results of simulations using GLMakie I would like to create a gui that allows me to view numerical data directly rather than graphically. I have been using the terminal and c…

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## [Which variable initialization is optimized away when variable unused?](https://discourse.julialang.org/t/which-variable-initialization-is-optimized-away-when-variable-unused/80587)

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**Author:** [@FireCrumb](https://discourse.julialang.org/u/FireCrumb)\
**Replies:** 2\
**Last updated:** [May 6, 2022, 5:39am UTC](https://discourse.julialang.org/t/which-variable-initialization-is-optimized-away-when-variable-unused/80587 "2022-05-06T05:39:24Z")

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I have a method where x is used, but y isn’t used. Why when I assign sqrt(100) to y then it’s ignored and not even executed (which is the desired behaviour), but when it’s assigned collect(1:100) then it is executed? I…

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## [Threading support for DataFrames transforms](https://discourse.julialang.org/t/threading-support-for-dataframes-transforms/79875)

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**Author:** [@jeremiedb](https://discourse.julialang.org/u/jeremiedb)\
**Replies:** 10\
**Last updated:** [May 6, 2022, 2:11am UTC](https://discourse.julialang.org/t/threading-support-for-dataframes-transforms/79875 "2022-05-06T02:11:15Z")

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With regard to multi-thread support with DataFrames, I understand that it remains a WIP. I wanted to validate whether some situations that appear, at least on the surface, like good candidates for to benefit from multi-…

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## [Given an object, return Julia code that defines the object](https://discourse.julialang.org/t/given-an-object-return-julia-code-that-defines-the-object/80579)

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**Author:** [@Ashlin\_Harris](https://discourse.julialang.org/u/Ashlin_Harris)\
**Replies:** 11\
**Last updated:** [May 6, 2022, 1:11am UTC](https://discourse.julialang.org/t/given-an-object-return-julia-code-that-defines-the-object/80579 "2022-05-06T01:11:16Z")

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Is there a function or macro that accepts an object and returns the Julia code that defines the object? For instance, is there a function f() with the following behaviour? julia\> X=Dict(\[("A", 1), ("B", 2)\]) Dict{String…

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## [Distributed functions, but never run concurrently](https://discourse.julialang.org/t/distributed-functions-but-never-run-concurrently/80519)

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**Author:** [@torrance](https://discourse.julialang.org/u/torrance)\
**Replies:** 3\
**Last updated:** [May 6, 2022, 2:03am UTC](https://discourse.julialang.org/t/distributed-functions-but-never-run-concurrently/80519 "2022-05-06T02:03:31Z")

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I have a function N functions f() that I want to run across a distributed set of M worker processes, where N functions \> M workers. Naively, I tried: for \_ in 1:N @spawnat :any f() end However, this runs f() concu…

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## [Indicator constraints with quadratic terms may have bugs?](https://discourse.julialang.org/t/indicator-constraints-with-quadratic-terms-may-have-bugs/80516)

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**Author:** [@iiitr](https://discourse.julialang.org/u/iiitr)\
**Replies:** 4\
**Last updated:** [May 6, 2022, 1:53am UTC](https://discourse.julialang.org/t/indicator-constraints-with-quadratic-terms-may-have-bugs/80516 "2022-05-06T01:53:47Z")

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When I use the indicator constraint, I find that it sometimes causes the model to be infeasible, but I can solve the model when I set a feasible solution as a constraint. I know that the indicator can only contain linea…

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## [How to approximate a function](https://discourse.julialang.org/t/how-to-approximate-a-function/80576)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 20\
**Last updated:** [May 6, 2022, 1:17am UTC](https://discourse.julialang.org/t/how-to-approximate-a-function/80576 "2022-05-06T01:17:22Z")

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I have the following function: function wind\_factor(height) log1 = log(height / 0.0002) / log(6.0 / 0.0002) exp1 = exp(0.08163 \* log(height/6.0)) return log1 + (log1 - exp1) end The parameter height is in …

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## [Gadfly and custom group colors](https://discourse.julialang.org/t/gadfly-and-custom-group-colors/80566)

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**Author:** [@gjh](https://discourse.julialang.org/u/gjh)\
**Replies:** 1\
**Last updated:** [May 6, 2022, 12:04am UTC](https://discourse.julialang.org/t/gadfly-and-custom-group-colors/80566 "2022-05-06T00:04:12Z")

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using Gadfly, DataFrames x=\[1,2,3,4,5,6\] y=\[6,5,4,3,2,1\] group=\[“a”, “b”, “a”, “b”,“a”, “b”\] df=DataFrame(x=x, y=y, group=group) Gadfly.plot(df, x=:x, y=:y, color=:group, Geom.point, Theme(background\_color=“ghos…

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## [\[ANN\] TableTransforms.jl v1.0: Transforms and pipelines with tabular data](https://discourse.julialang.org/t/ann-tabletransforms-jl-v1-0-transforms-and-pipelines-with-tabular-data/80572)

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**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\
**Replies:** 2\
**Last updated:** [May 5, 2022, 10:56pm UTC](https://discourse.julialang.org/t/ann-tabletransforms-jl-v1-0-transforms-and-pipelines-with-tabular-data/80572 "2022-05-05T22:56:48Z")

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TableTransforms.jl v1.0 is out signaling that we reached a stable API :tada: The list of available transforms is growing quickly: https://juliaml.github.io/TableTransforms.jl/stable/transforms/builtin Issues and PRs …

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## [DC load flow constraint](https://discourse.julialang.org/t/dc-load-flow-constraint/80564)

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**Author:** [@mbah](https://discourse.julialang.org/u/mbah)\
**Replies:** 2\
**Last updated:** [May 5, 2022, 10:19pm UTC](https://discourse.julialang.org/t/dc-load-flow-constraint/80564 "2022-05-05T22:19:50Z")

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Hello, I am trying to fit in a DC load flow equation into my zonal dispatch model without much success. #using DataFrames, JuMp generators = DataFrame(index = \["conventional\_gas", "conventional\_nuc", "West\_A\_Wind", "…

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## [Makie recipe with plots being added on the fly and why does the recipe run so long](https://discourse.julialang.org/t/makie-recipe-with-plots-being-added-on-the-fly-and-why-does-the-recipe-run-so-long/80539)

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**Author:** [@kunzaatko](https://discourse.julialang.org/u/kunzaatko)\
**Replies:** 3\
**Last updated:** [May 5, 2022, 9:17pm UTC](https://discourse.julialang.org/t/makie-recipe-with-plots-being-added-on-the-fly-and-why-does-the-recipe-run-so-long/80539 "2022-05-05T21:17:10Z")

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I am trying to make a Makie recipe for a sequence of images with the current image frame from the sequence being an Observable (frame). I would like to have the separate frames of the image load on demand, when the frame …

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## [Sum elements of a struct](https://discourse.julialang.org/t/sum-elements-of-a-struct/80559)

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**Author:** [@vamp](https://discourse.julialang.org/u/vamp)\
**Replies:** 7\
**Last updated:** [May 5, 2022, 9:13pm UTC](https://discourse.julialang.org/t/sum-elements-of-a-struct/80559 "2022-05-05T21:13:17Z")

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How can I sum the elements of MyStruct? Code: struct MyStruct a::Int b::SVector{N\_lds, Int64} c::Int end import Base: - -(x::MyStruct, y::MyStruct) = MyS…

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## [\[ANN\] NumaAllocators.jl: Non-Uniform Memory Access extension of ArrayAllocators.jl for HPC](https://discourse.julialang.org/t/ann-numaallocators-jl-non-uniform-memory-access-extension-of-arrayallocators-jl-for-hpc/80565)

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**Author:** [@mkitti](https://discourse.julialang.org/u/mkitti)\
**Replies:** 1\
**Last updated:** [May 5, 2022, 9:11pm UTC](https://discourse.julialang.org/t/ann-numaallocators-jl-non-uniform-memory-access-extension-of-arrayallocators-jl-for-hpc/80565 "2022-05-05T21:11:36Z")

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NumaAllocators.jl NumaAllocators.jl extends ArrayAllocators.jl to provide a mechanism for allocating arrays on specific Non-Uniform Memory Access nodes. NumaAllocators.jl is a subdirectory package within the ArrayAllocat…

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## [Best way to specify a filename inside a function](https://discourse.julialang.org/t/best-way-to-specify-a-filename-inside-a-function/80263)

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**Author:** [@chadagreene](https://discourse.julialang.org/u/chadagreene)\
**Replies:** 22\
**Last updated:** [May 5, 2022, 8:36pm UTC](https://discourse.julialang.org/t/best-way-to-specify-a-filename-inside-a-function/80263 "2022-05-05T20:36:55Z")

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I’m writing a package containing a function that will load a data file, let’s call it data.txt. I’m assuming the user has already obtained data.txt from some other source, and the file exists somewhere on their computer. …

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## [Impenetrable error message](https://discourse.julialang.org/t/impenetrable-error-message/80554)

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**Author:** [@PetrKryslUCSD](https://discourse.julialang.org/u/PetrKryslUCSD)\
**Replies:** 12\
**Last updated:** [May 5, 2022, 8:14pm UTC](https://discourse.julialang.org/t/impenetrable-error-message/80554 "2022-05-05T20:14:44Z")

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I would not be surprised if novices were stumped. I certainly am: (JuliaTutorial) pkg\> add FinEtoolsHeatDiff Resolving package versions... ERROR: Unsatisfiable requirements detected for package FinEtoolsHeatDiff \[972…

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## [\[ANN\] ArrayAllocators.jl: Integrating calloc and aligned memory into Array construction](https://discourse.julialang.org/t/ann-arrayallocators-jl-integrating-calloc-and-aligned-memory-into-array-construction/80356)

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**Author:** [@mkitti](https://discourse.julialang.org/u/mkitti)\
**Replies:** 14\
**Last updated:** [May 5, 2022, 7:48pm UTC](https://discourse.julialang.org/t/ann-arrayallocators-jl-integrating-calloc-and-aligned-memory-into-array-construction/80356 "2022-05-05T19:48:04Z")

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ArrayAllocators.jl I am happy to announce ArrayAllocators.jl, a registered package that provides new mechanisms of array allocation. ArrayAllocators.jl provides new values that can take the place of undef when constructi…

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## [Tracking JIT compiled objects](https://discourse.julialang.org/t/tracking-jit-compiled-objects/80553)

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**Author:** [@felipenoris](https://discourse.julialang.org/u/felipenoris)\
**Replies:** 1\
**Last updated:** [May 5, 2022, 6:35pm UTC](https://discourse.julialang.org/t/tracking-jit-compiled-objects/80553 "2022-05-05T18:35:22Z")

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Hi! I’m getting a lot of memory consumption on my Julia sessions after running some heavy workloads. My best bet is that I’m JIT compiling too many functions and maybe I need to use nospecialize somewhere. What’s the b…

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