# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1281

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

**Page:** 1282

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## [How to filter data with masks and update with new values](https://discourse.julialang.org/t/how-to-filter-data-with-masks-and-update-with-new-values/67387)

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**Author:** [@hdcpereira](https://discourse.julialang.org/u/hdcpereira)\
**Replies:** 3\
**Last updated:** [August 31, 2021, 12:13am UTC](https://discourse.julialang.org/t/how-to-filter-data-with-masks-and-update-with-new-values/67387 "2021-08-31T00:13:30Z")

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Hello there. I’m trying to rewrite a function that I wrote in Python but I have no idea how to do it. My Python function is: def R( A1, A2 ): phi = np.linspace(0,np.pi,1000) Rec = ( 4\*A1\*A2 / (A1 + A2)\*\*2 ) \* np.c…

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## [Makie: layout of IntervalSlider and Slider and custom labels/text display](https://discourse.julialang.org/t/makie-layout-of-intervalslider-and-slider-and-custom-labels-text-display/67241)

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**Author:** [@Audrius-St](https://discourse.julialang.org/u/Audrius-St)\
**Replies:** 8\
**Last updated:** [August 30, 2021, 11:47pm UTC](https://discourse.julialang.org/t/makie-layout-of-intervalslider-and-slider-and-custom-labels-text-display/67241 "2021-08-30T23:47:35Z")

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Hello, Three questions regarding Makie layout of IntervalSlider and Slider. On the left side of the above image, I would like to have a :grey10 background for the IntervalSlider and Slider as in the Textbox. Howev…

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## [SymPy/Symbolics and HCubature](https://discourse.julialang.org/t/sympy-symbolics-and-hcubature/56513)

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**Author:** [@Aleksandr\_Mikheev](https://discourse.julialang.org/u/Aleksandr_Mikheev)\
**Replies:** 13\
**Last updated:** [August 30, 2021, 11:11pm UTC](https://discourse.julialang.org/t/sympy-symbolics-and-hcubature/56513 "2021-08-30T23:11:43Z")

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Hi everyone! I was not sure whether to post it here or in the Numerics subforum, but given that my question is very basic I decided to go for this section. Let’s say I want to integrate some function f(x,y) over \[a\_1,b\_…

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## [PlotlyJS: restyle! not working inside Pluto -- how to change labels?](https://discourse.julialang.org/t/plotlyjs-restyle-not-working-inside-pluto-how-to-change-labels/67381)

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**Author:** [@VivMendes](https://discourse.julialang.org/u/VivMendes)\
**Replies:** 0\
**Last updated:** [August 30, 2021, 9:39pm UTC](https://discourse.julialang.org/t/plotlyjs-restyle-not-working-inside-pluto-how-to-change-labels/67381 "2021-08-30T21:39:15Z")

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I am stuck with a stupid small detail. I have two outputs from a loop, both of which are 1×16 Matrix{Float64}. I know how to plot the two outputs together on a single plot. The point is that is I do not know how to chang…

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## [How to print a vector with only 2 decimal places](https://discourse.julialang.org/t/how-to-print-a-vector-with-only-2-decimal-places/67368)

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**Author:** [@dgpdx](https://discourse.julialang.org/u/dgpdx)\
**Replies:** 21\
**Last updated:** [August 30, 2021, 6:55pm UTC](https://discourse.julialang.org/t/how-to-print-a-vector-with-only-2-decimal-places/67368 "2021-08-30T18:55:51Z")

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I’m trying to print a vector x with 2 decimal places, but this: @sprintf("%.2f ",x) gives an error: ERROR: MethodError: no method matching Float64(::Matrix{Float64}) Is there a way to apply “%.2f” to an entire vector…

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## [Compute double multipole expansion](https://discourse.julialang.org/t/compute-double-multipole-expansion/67059)

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**Author:** [@mleprovost](https://discourse.julialang.org/u/mleprovost)\
**Replies:** 6\
**Last updated:** [August 30, 2021, 6:53pm UTC](https://discourse.julialang.org/t/compute-double-multipole-expansion/67059 "2021-08-30T18:53:06Z")

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Hello, I am working on the calculation of the pressure induced at d locations \\{\\xi\_1, \\ldots, \\xi\_d\\} due to a set of n singularities located at \\{z\_1, \\ldots, z\_n\\} with strength \\{ S\_1, \\ldots, S\_n\\}, where \\xi\_i, z\_…

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## [Hide output from external function](https://discourse.julialang.org/t/hide-output-from-external-function/67000)

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**Author:** [@lmiq](https://discourse.julialang.org/u/lmiq)\
**Replies:** 8\
**Last updated:** [August 30, 2021, 6:47pm UTC](https://discourse.julialang.org/t/hide-output-from-external-function/67000 "2021-08-30T18:47:57Z")

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I am using a package, Chemfiles, which has a function to read some simulation trajectory files. This function is a wrapper to a C++ function, and this C++ function writes to “the screen” (?) some stuff every time a file …

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## [Convert Any\["0.30", "0.34"\] to \[0.30, 0.34\]](https://discourse.julialang.org/t/convert-any-0-30-0-34-to-0-30-0-34/67374)

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**Author:** [@Nenndul](https://discourse.julialang.org/u/Nenndul)\
**Replies:** 7\
**Last updated:** [August 30, 2021, 6:11pm UTC](https://discourse.julialang.org/t/convert-any-0-30-0-34-to-0-30-0-34/67374 "2021-08-30T18:11:36Z")

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I have a little program working and am trying to get the data read in from a file. After poking around a little I found the following method: using Queryverse open(“data.csv”) do f # line\_number line = 0 # read till…

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## [Gamma correction for colormaps](https://discourse.julialang.org/t/gamma-correction-for-colormaps/67227)

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**Author:** [@RainerHeintzmann](https://discourse.julialang.org/u/RainerHeintzmann)\
**Replies:** 8\
**Last updated:** [August 30, 2021, 5:56pm UTC](https://discourse.julialang.org/t/gamma-correction-for-colormaps/67227 "2021-08-30T17:56:44Z")

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Is there a way to have a gamma Node, which is linked to the gamma value of a colormap in Makie? Colorbars can have limits, but no gamma yet as it seems. Is it possible to implement this into Makie or can one write a col…

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## [Taking advantage of rowwise-constant sparse matrix](https://discourse.julialang.org/t/taking-advantage-of-rowwise-constant-sparse-matrix/67366)

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**Author:** [@lrnv](https://discourse.julialang.org/u/lrnv)\
**Replies:** 7\
**Last updated:** [August 30, 2021, 4:48pm UTC](https://discourse.julialang.org/t/taking-advantage-of-rowwise-constant-sparse-matrix/67366 "2021-08-30T16:48:58Z")

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Hi, This is a follow-up of this previous thread where we discussed with @Sukera the possibility to improve matrix-vector product in the case where the matrix is sparse, but also has only one possible non-zero value per …

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## [How to resize REPL without exiting julia?](https://discourse.julialang.org/t/how-to-resize-repl-without-exiting-julia/67372)

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**Author:** [@mkarikom](https://discourse.julialang.org/u/mkarikom)\
**Replies:** 0\
**Last updated:** [August 30, 2021, 4:51pm UTC](https://discourse.julialang.org/t/how-to-resize-repl-without-exiting-julia/67372 "2021-08-30T16:51:35Z")

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Question: How can I resize the REPL without exiting julia? Background: In the example above I just started julia within an ssh session on an hpc compute node, I have to do it this way because the vscode julia termina…

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## [Call for a data structure that is: multi-dimensional, columnar-typed, and in-memory in the core Julia language](https://discourse.julialang.org/t/call-for-a-data-structure-that-is-multi-dimensional-columnar-typed-and-in-memory-in-the-core-julia-language/64524)

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**Author:** [@aiqc](https://discourse.julialang.org/u/aiqc)\
**Replies:** 15\
**Last updated:** [August 30, 2021, 4:42pm UTC](https://discourse.julialang.org/t/call-for-a-data-structure-that-is-multi-dimensional-columnar-typed-and-in-memory-in-the-core-julia-language/64524 "2021-08-30T16:42:49Z")

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It appears that the entire Julia data science ecosystem is built around Julia’s Array. However, from what I’ve observed, Array’s flexibility makes it too disuniform to serve as an in-memory data structure for sharing inf…

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## [Pluto not accepting repl packages](https://discourse.julialang.org/t/pluto-not-accepting-repl-packages/67360)

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**Author:** [@cybervigilante](https://discourse.julialang.org/u/cybervigilante)\
**Replies:** 5\
**Last updated:** [August 30, 2021, 4:36pm UTC](https://discourse.julialang.org/t/pluto-not-accepting-repl-packages/67360 "2021-08-30T16:36:12Z")

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When I add a package in the repl I can see it in Jupyter and my editor, but not in Pluto. I hate to dupe packages and waste limited disk space. Is there any way to make Pluto coordinate?

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## [How to improve runtime with measurements.jl?](https://discourse.julialang.org/t/how-to-improve-runtime-with-measurements-jl/67343)

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**Author:** [@Cevheriferd](https://discourse.julialang.org/u/Cevheriferd)\
**Replies:** 11\
**Last updated:** [August 30, 2021, 4:35pm UTC](https://discourse.julialang.org/t/how-to-improve-runtime-with-measurements-jl/67343 "2021-08-30T16:35:19Z")

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Dear all, I am using the measurements.jl package to calculate the error in my dataset. I have an array with voltage values which all have their own uncertainty. But when I want to calculate the mean of the array, it tak…

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## [Unexpected allocations when accessing IdDict](https://discourse.julialang.org/t/unexpected-allocations-when-accessing-iddict/65996)

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**Author:** [@StefanMathis](https://discourse.julialang.org/u/StefanMathis)\
**Replies:** 9\
**Last updated:** [August 30, 2021, 4:28pm UTC](https://discourse.julialang.org/t/unexpected-allocations-when-accessing-iddict/65996 "2021-08-30T16:28:18Z")

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Hello, I found that accessing an IdDict can lead to memory allocations, while accessing a Dict does not. I first encountered this behaviour in combination with the Memoization.jl package, therefore the original thread c…

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## [Test fails when run through Pkg.test() but not when run interactively](https://discourse.julialang.org/t/test-fails-when-run-through-pkg-test-but-not-when-run-interactively/67352)

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**Author:** [@Tomas\_Pevny](https://discourse.julialang.org/u/Tomas_Pevny)\
**Replies:** 6\
**Last updated:** [August 30, 2021, 4:07pm UTC](https://discourse.julialang.org/t/test-fails-when-run-through-pkg-test-but-not-when-run-interactively/67352 "2021-08-30T16:07:38Z")

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Hello, we have encountered a weird error. We have some package and when I run the test in repl, the test fails. But when we run the tests using Pkg.test(), the test fails. We have been expecting that it is due to diffe…

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## [Term representation in SymbolicUtils/Symbolics -- rational polynomial form, and future changes](https://discourse.julialang.org/t/term-representation-in-symbolicutils-symbolics-rational-polynomial-form-and-future-changes/67367)

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**Author:** [@shashi](https://discourse.julialang.org/u/shashi)\
**Replies:** 0\
**Last updated:** [August 30, 2021, 3:57pm UTC](https://discourse.julialang.org/t/term-representation-in-symbolicutils-symbolics-rational-polynomial-form-and-future-changes/67367 "2021-08-30T15:57:33Z")

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Hi all! I wanted to post an update about the recent changes in SymbolicUtils that I’m looking forward to bug-fixing and making very good. An explanation of this representation is written up here In summary, we have …

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## [What are all the other packages that list when adding one](https://discourse.julialang.org/t/what-are-all-the-other-packages-that-list-when-adding-one/67319)

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**Author:** [@cybervigilante](https://discourse.julialang.org/u/cybervigilante)\
**Replies:** 3\
**Last updated:** [August 30, 2021, 3:58pm UTC](https://discourse.julialang.org/t/what-are-all-the-other-packages-that-list-when-adding-one/67319 "2021-08-30T15:58:44Z")

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When I add a Pkg in the REPL, I see a dozen or two other packages fly by. What are they? Are they also being added and if so, why can’t I use them?

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## [Libraries for constrained genetics algorithm](https://discourse.julialang.org/t/libraries-for-constrained-genetics-algorithm/66978)

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**Author:** [@Hilaire\_Foillard](https://discourse.julialang.org/u/Hilaire_Foillard)\
**Replies:** 7\
**Last updated:** [August 30, 2021, 3:24pm UTC](https://discourse.julialang.org/t/libraries-for-constrained-genetics-algorithm/66978 "2021-08-30T15:24:48Z")

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Hello, I’m an engineer in operational research and I was working on a MILP. Since the problem was to big I decided to use Benders cut. But it’s still very big so I want to change my method and to use genetics algorithm. …

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## [How to avoid evaluation into the global space when the expression is not know in advance](https://discourse.julialang.org/t/how-to-avoid-evaluation-into-the-global-space-when-the-expression-is-not-know-in-advance/67342)

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**Author:** [@JianghuiDu](https://discourse.julialang.org/u/JianghuiDu)\
**Replies:** 31\
**Last updated:** [August 30, 2021, 3:05pm UTC](https://discourse.julialang.org/t/how-to-avoid-evaluation-into-the-global-space-when-the-expression-is-not-know-in-advance/67342 "2021-08-30T15:05:00Z")

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input = Dict("x"=\>ones(10),"y"=\>2\*ones(10),"z"=\>3\*ones(10)) expr\_list = DataFrame(var=\["v1","v2","v3"\],expr = \["x\*y","y/z","x+y+z"\]) output = Dict() I have a dictionary of input storing the values of some variables x,…

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## [How to run multiple threads, all using the same sequence of pseudorandom numbers, in Julia?](https://discourse.julialang.org/t/how-to-run-multiple-threads-all-using-the-same-sequence-of-pseudorandom-numbers-in-julia/67334)

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**Author:** [@erwanlecarpentier](https://discourse.julialang.org/u/erwanlecarpentier)\
**Replies:** 9\
**Last updated:** [August 30, 2021, 2:22pm UTC](https://discourse.julialang.org/t/how-to-run-multiple-threads-all-using-the-same-sequence-of-pseudorandom-numbers-in-julia/67334 "2021-08-30T14:22:19Z")

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Hey! I would like to run a function multiple times in parallel using the same sequence of random numbers for each call. The only thing that should change between each call is some given parameters. Here is a MWE using R…

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## [Thread safe cache](https://discourse.julialang.org/t/thread-safe-cache/62210)

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**Author:** [@maarten\_van\_damme](https://discourse.julialang.org/u/maarten_van_damme)\
**Replies:** 4\
**Last updated:** [August 30, 2021, 1:44pm UTC](https://discourse.julialang.org/t/thread-safe-cache/62210 "2021-08-30T13:44:12Z")

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I’ve been running into issues with WignerSymbols.jl, where one of the necessary operations is calculating the prime factorization of certain numbers. To speed this up you’d want to cache any found prime factors, and this…

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## [All about totalvar](https://discourse.julialang.org/t/all-about-totalvar/67350)

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**Author:** [@Naba7](https://discourse.julialang.org/u/Naba7)\
**Replies:** 2\
**Last updated:** [August 30, 2021, 1:31pm UTC](https://discourse.julialang.org/t/all-about-totalvar/67350 "2021-08-30T13:31:49Z")

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The official docs of totalvar(X) says if X is a matrix, then the totalvar(X) == sum(Diagonal(X)) but clearly in the testsit is showing a different value. You can check line 146.

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## [Code review for my first package](https://discourse.julialang.org/t/code-review-for-my-first-package/58574)

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**Author:** [@Ihar\_Kudraucau](https://discourse.julialang.org/u/Ihar_Kudraucau)\
**Replies:** 1\
**Last updated:** [August 30, 2021, 12:32pm UTC](https://discourse.julialang.org/t/code-review-for-my-first-package/58574 "2021-08-30T12:32:01Z")

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Hello colleagues, I’ve created my first Julia package: GitHub - xyxel/RedisGraph.jl: RedisGraph Julia client I will be very grateful if somebody review the package in order to check that code is Julia-friendly. Thank …

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## [(Not) Giving up on dispatch](https://discourse.julialang.org/t/not-giving-up-on-dispatch/66797)

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**Author:** [@Bardo](https://discourse.julialang.org/u/Bardo)\
**Replies:** 23\
**Last updated:** [August 30, 2021, 12:05pm UTC](https://discourse.julialang.org/t/not-giving-up-on-dispatch/66797 "2021-08-30T12:05:47Z")

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In another post, I got the comment …the code you’ve posted here was not one of the recommended ways of doing … Reason is, I could not reasonably put all conditions into regular dispatch (functions with the same name …

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## [PyPlot plot\_date issue (year 3990) - Solved](https://discourse.julialang.org/t/pyplot-plot-date-issue-year-3990-solved/67345)

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**Author:** [@Daneel](https://discourse.julialang.org/u/Daneel)\
**Replies:** 0\
**Last updated:** [August 30, 2021, 12:05pm UTC](https://discourse.julialang.org/t/pyplot-plot-date-issue-year-3990-solved/67345 "2021-08-30T12:05:38Z")

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Recently I installed Julia on a new computer and using code I knew that works, PyPlot displayed dates far in the future. I was plotting data from the previous week (August 2021) and plot\_date was displaying the dates in …

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## [FunctionWrappers and kwargs](https://discourse.julialang.org/t/functionwrappers-and-kwargs/67339)

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**Author:** [@pablosanjose](https://discourse.julialang.org/u/pablosanjose)\
**Replies:** 1\
**Last updated:** [August 30, 2021, 11:21am UTC](https://discourse.julialang.org/t/functionwrappers-and-kwargs/67339 "2021-08-30T11:21:27Z")

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I see FunctionWrappers.jl as a critical tool to enable precompilation of code that takes functions as inputs, and hence reduce latency in such cases. I think the package is a crucial tool in the Julia language, since the…

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## [Helps with English: "cosmetic sugar" expression ? No it is not that!](https://discourse.julialang.org/t/helps-with-english-cosmetic-sugar-expression-no-it-is-not-that/67024)

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**Author:** [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Replies:** 3\
**Last updated:** [August 30, 2021, 11:16am UTC](https://discourse.julialang.org/t/helps-with-english-cosmetic-sugar-expression-no-it-is-not-that/67024 "2021-08-30T11:16:53Z")

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Arghh… I have one English expression in mind but I don’t remember it: “This \[a certain feature, here the possibility to use Unicode in variable names\] seems just cosmetic sugar, but it really helps…” Here I want to say…

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## [How to avoid full specialization of \`haskey(::Dict, key)\` on the caller side](https://discourse.julialang.org/t/how-to-avoid-full-specialization-of-haskey-dict-key-on-the-caller-side/67323)

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**Author:** [@kimikage](https://discourse.julialang.org/u/kimikage)\
**Replies:** 6\
**Last updated:** [August 30, 2021, 10:56am UTC](https://discourse.julialang.org/t/how-to-avoid-full-specialization-of-haskey-dict-key-on-the-caller-side/67323 "2021-08-30T10:56:36Z")

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I don’t understand the details of the implementation of Dict, but I don’t think the V in Dict{K,V} is involved in the “essential functionality” in haskey. For example, when I start a REPL session, there are method insta…

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## [AI and Deep Learning in Grading Prostate Cancer using histology slide and Magnetic Resonance Imaging (MRI) of prostate gland](https://discourse.julialang.org/t/ai-and-deep-learning-in-grading-prostate-cancer-using-histology-slide-and-magnetic-resonance-imaging-mri-of-prostate-gland/67330)

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**Author:** [@anilgavade](https://discourse.julialang.org/u/anilgavade)\
**Replies:** 2\
**Last updated:** [August 30, 2021, 9:54am UTC](https://discourse.julialang.org/t/ai-and-deep-learning-in-grading-prostate-cancer-using-histology-slide-and-magnetic-resonance-imaging-mri-of-prostate-gland/67330 "2021-08-30T09:54:38Z")

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Dear All, This is Professor Anil B. Gavade, from Belagavi, India. I am currently working on project, Grading Prostate Cancer using histology slide and Magnetic Resonance Imaging (MRI) of prostate gland. Planning to use…

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