# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1772

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

**Page:** 1773

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## [Cool chart grids](https://discourse.julialang.org/t/cool-chart-grids/37712)

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**Author:** [@lewis](https://discourse.julialang.org/u/lewis)\
**Replies:** 2\
**Last updated:** [April 17, 2020, 3:35pm UTC](https://discourse.julialang.org/t/cool-chart-grids/37712 "2020-04-17T15:35:44Z")

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I wanted to better understand the effects of the parameters for the gamma and Erlang distributions. I didn’t quite intuit the effects based on the formulas for the probability density function. Carefully studying code e…

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## [Unable to fit example Turing model](https://discourse.julialang.org/t/unable-to-fit-example-turing-model/37764)

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**Author:** [@jacobcvt12](https://discourse.julialang.org/u/jacobcvt12)\
**Replies:** 1\
**Last updated:** [April 17, 2020, 2:49pm UTC](https://discourse.julialang.org/t/unable-to-fit-example-turing-model/37764 "2020-04-17T14:49:43Z")

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The following code, copied from the Turing website throws an error using Turing using StatsPlots # Define a simple Normal model with unknown mean and variance. @model gdemo(x, y) = begin s ~ InverseGamma(2, 3) m ~ …

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## [Question about CUDA-aware MPI](https://discourse.julialang.org/t/question-about-cuda-aware-mpi/37487)

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**Author:** [@marius311](https://discourse.julialang.org/u/marius311)\
**Replies:** 1\
**Last updated:** [April 17, 2020, 2:25pm UTC](https://discourse.julialang.org/t/question-about-cuda-aware-mpi/37487 "2020-04-17T14:25:00Z")

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I’d like to make sure I understand how Julia hooks in to CUDA-aware MPI. Basically, is it true that when send/receiving Julia objects which may have a CuArray somewhere in them, that the CuArray is never moved to the CPU…

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## [Minkowski sum in julia](https://discourse.julialang.org/t/minkowski-sum-in-julia/7004)

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**Author:** [@Sharabh\_Shukla](https://discourse.julialang.org/u/Sharabh_Shukla)\
**Replies:** 1\
**Last updated:** [April 17, 2020, 12:52pm UTC](https://discourse.julialang.org/t/minkowski-sum-in-julia/7004 "2020-04-17T12:52:12Z")

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I have new hundred polytopes in H representation. I would like to find the Minkowski sum of all these polytopes, I am aware that the problem is difficult I was looking for an approximate algorithm in julia that can do t…

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## [Why do chains not converge in BNN](https://discourse.julialang.org/t/why-do-chains-not-converge-in-bnn/37730)

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**Author:** [@Farlein](https://discourse.julialang.org/u/Farlein)\
**Replies:** 3\
**Last updated:** [April 17, 2020, 1:09pm UTC](https://discourse.julialang.org/t/why-do-chains-not-converge-in-bnn/37730 "2020-04-17T13:09:49Z")

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Hi there, I continue to learn Turing. In the tutorial for Bayesian Logistic Regression (https://turing.ml/dev/tutorials/2-logisticregression/), there is a section to check the trend plots of the chains, in order to “do …

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## [Plotting Unit Vectors](https://discourse.julialang.org/t/plotting-unit-vectors/37740)

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**Author:** [@ennvvy](https://discourse.julialang.org/u/ennvvy)\
**Replies:** 1\
**Last updated:** [April 17, 2020, 12:26pm UTC](https://discourse.julialang.org/t/plotting-unit-vectors/37740 "2020-04-17T12:26:34Z")

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I want to plot unit vectors whose orientation varies from \[-pi, pi\]. A reference figure is below. Any suggestions on how I can get the desired plot?

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## [What has the function \`expand\` been renamed to?](https://discourse.julialang.org/t/what-has-the-function-expand-been-renamed-to/37756)

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**Author:** [@jishnub](https://discourse.julialang.org/u/jishnub)\
**Replies:** 1\
**Last updated:** [April 17, 2020, 12:26pm UTC](https://discourse.julialang.org/t/what-has-the-function-expand-been-renamed-to/37756 "2020-04-17T12:26:17Z")

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I came across this old thread on literal\_pow where the suggestion to introspect code is to use julia\> @eval @which $(expand(:(1^2))) literal\_pow(::Base.#^, x::Union{Complex{#s37} where #s37\<:Union{Float32, Float64, Int1…

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## [How should I approach GPU programming?](https://discourse.julialang.org/t/how-should-i-approach-gpu-programming/37666)

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**Author:** [@Ahmed\_Salih](https://discourse.julialang.org/u/Ahmed_Salih)\
**Replies:** 27\
**Last updated:** [April 17, 2020, 12:16pm UTC](https://discourse.julialang.org/t/how-should-i-approach-gpu-programming/37666 "2020-04-17T12:16:24Z")

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Hello! This is the first time I have really dived into GPU programming. I have followed along this tutorial, https://juliagpu.gitlab.io/CUDA.jl/tutorials/introduction/, and have started getting a feel for how to do some…

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## [Introduce ++ as the concatenation operator](https://discourse.julialang.org/t/introduce-as-the-concatenation-operator/37418)

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**Author:** [@CameronBieganek](https://discourse.julialang.org/u/CameronBieganek)\
**Replies:** 60\
**Last updated:** [April 17, 2020, 12:23pm UTC](https://discourse.julialang.org/t/introduce-as-the-concatenation-operator/37418 "2020-04-17T12:23:38Z")

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It seems like it would be handy to have ++ as a generic concatenation operator. There are a few languages that use ++ for this, e.g. Erlang, Haskell, and Elm. For arrays, ++ would be sugar for vcat (hcat is another story…

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## [Parallel computing: running from terminal vs. editor. Same code, missing parallelisation](https://discourse.julialang.org/t/parallel-computing-running-from-terminal-vs-editor-same-code-missing-parallelisation/37708)

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**Author:** [@galaverna](https://discourse.julialang.org/u/galaverna)\
**Replies:** 0\
**Last updated:** [April 16, 2020, 5:23pm UTC](https://discourse.julialang.org/t/parallel-computing-running-from-terminal-vs-editor-same-code-missing-parallelisation/37708 "2020-04-16T17:23:44Z")

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Hello! I am getting started with Julia parallel computing and I successfully created a code that runs on different workers when launched from the Atom editor. However, I am facing some problems when running the same cod…

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## [Can't get Juno to launch anymore](https://discourse.julialang.org/t/cant-get-juno-to-launch-anymore/37747)

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**Author:** [@samantp](https://discourse.julialang.org/u/samantp)\
**Replies:** 6\
**Last updated:** [April 17, 2020, 10:07am UTC](https://discourse.julialang.org/t/cant-get-juno-to-launch-anymore/37747 "2020-04-17T10:07:45Z")

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I am trying get Juno to launch but for the life of me can’t figure out how to do so. I have uninstalled and re-installed it but atom does not open the pane on the left featuring the Julia run, stop, etc. buttons. I also …

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## [Declaring types from packages](https://discourse.julialang.org/t/declaring-types-from-packages/37737)

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**Author:** [@amejia83](https://discourse.julialang.org/u/amejia83)\
**Replies:** 6\
**Last updated:** [April 17, 2020, 8:31am UTC](https://discourse.julialang.org/t/declaring-types-from-packages/37737 "2020-04-17T08:31:51Z")

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Hello, I am facing an issue that I’m sure is very minor, but I cannot find anything in the documentation for either the package or Julia documentation. I’m hoping that someone here can help me out (without knowing too mu…

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## [RFC: Speeding up code loading when using multiple processes by 2X](https://discourse.julialang.org/t/rfc-speeding-up-code-loading-when-using-multiple-processes-by-2x/37583)

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**Author:** [@marius311](https://discourse.julialang.org/u/marius311)\
**Replies:** 5\
**Last updated:** [April 17, 2020, 7:04am UTC](https://discourse.julialang.org/t/rfc-speeding-up-code-loading-when-using-multiple-processes-by-2x/37583 "2020-04-17T07:04:51Z")

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I have a proposal which I could implement, but wanted to see if there’s any relevant things I may well be missing before embarking on it. As you know, when you have multiple Julia processes and do using Foo or even @eve…

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## [Contact Tracing Analytics - an opportunity](https://discourse.julialang.org/t/contact-tracing-analytics-an-opportunity/37741)

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**Author:** [@johnh](https://discourse.julialang.org/u/johnh)\
**Replies:** 0\
**Last updated:** [April 17, 2020, 6:52am UTC](https://discourse.julialang.org/t/contact-tracing-analytics-an-opportunity/37741 "2020-04-17T06:52:39Z")

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I work as a solutions architect for a very large technology company. If you or your company are working on contact tracing analytics please drop me a message.

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## [Cd() directory out of C:\\\\ or D:\\\\](https://discourse.julialang.org/t/cd-directory-out-of-c-or-d/37634)

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**Author:** [@1634](https://discourse.julialang.org/u/1634)\
**Replies:** 13\
**Last updated:** [April 17, 2020, 6:19am UTC](https://discourse.julialang.org/t/cd-directory-out-of-c-or-d/37634 "2020-04-17T06:19:55Z")

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According to Filesystem · The Julia Language I’d like to julia\> cd("/home/amend") ERROR: IOError: chdir /home/amend: no such file or directory (ENOENT) while julia\> cd("D:\\\\Julia") #working \*\*Is it a must to start f…

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## [Type inference fails for broadcasted addition of tuples containing multiple types](https://discourse.julialang.org/t/type-inference-fails-for-broadcasted-addition-of-tuples-containing-multiple-types/37725)

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**Author:** [@tomohiro\_soejima](https://discourse.julialang.org/u/tomohiro_soejima)\
**Replies:** 3\
**Last updated:** [April 17, 2020, 6:19am UTC](https://discourse.julialang.org/t/type-inference-fails-for-broadcasted-addition-of-tuples-containing-multiple-types/37725 "2020-04-17T06:19:34Z")

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Hi, I want to write addition function for tuples with unknown length and unknown type e.g. something like Tuple{a, b, c, d...} where the length and type is determined at runtime, and a, b, c, and d are custom types with…

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## [Do I have to re-add the package after upgrading Julia to a newer versions?](https://discourse.julialang.org/t/do-i-have-to-re-add-the-package-after-upgrading-julia-to-a-newer-versions/37729)

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**Author:** [@Haolun\_Li](https://discourse.julialang.org/u/Haolun_Li)\
**Replies:** 3\
**Last updated:** [April 17, 2020, 5:18am UTC](https://discourse.julialang.org/t/do-i-have-to-re-add-the-package-after-upgrading-julia-to-a-newer-versions/37729 "2020-04-17T05:18:36Z")

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I upgraded my Julia from 1.3 to 1.4 today. But using some\_pkg where some\_pkg is a package I added when using v1.3 no longer works. Do I have to re-add all the packages again in 1.4 or is there an easy way for me to reloc…

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## [Extract elements of NamedTuple](https://discourse.julialang.org/t/extract-elements-of-namedtuple/37731)

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**Author:** [@Jing\_Zhang](https://discourse.julialang.org/u/Jing_Zhang)\
**Replies:** 2\
**Last updated:** [April 17, 2020, 5:10am UTC](https://discourse.julialang.org/t/extract-elements-of-namedtuple/37731 "2020-04-17T05:10:18Z")

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Hi Julia users, I was trying to extract multiple elements from a NamedTuple and Failed. It works for extracting one element (pt here is a NamedTuple) through the following code line pt\[:cancer\_type\] But doesn’t work …

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## [V1.4 failed to precompile PyCall and PyPlot on windows 7 x64](https://discourse.julialang.org/t/v1-4-failed-to-precompile-pycall-and-pyplot-on-windows-7-x64/37718)

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**Author:** [@fhkm](https://discourse.julialang.org/u/fhkm)\
**Replies:** 8\
**Last updated:** [April 17, 2020, 4:38am UTC](https://discourse.julialang.org/t/v1-4-failed-to-precompile-pycall-and-pyplot-on-windows-7-x64/37718 "2020-04-17T04:38:07Z")

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I initially would like to use PyPlot. The error message prompted me to rebuild PyCall. V1.4, Windows 7 x64. I then use this command using Pkg Pkg.build(“PyCall”) But it did not solve the problem. I was unable to b…

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## [Turing.jl - Binomial ArgumentError zero(p) \<= p \<= one(p) is not satisfied](https://discourse.julialang.org/t/turing-jl-binomial-argumenterror-zero-p-p-one-p-is-not-satisfied/37601)

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**Author:** [@mangulo](https://discourse.julialang.org/u/mangulo)\
**Replies:** 9\
**Last updated:** [April 17, 2020, 2:26am UTC](https://discourse.julialang.org/t/turing-jl-binomial-argumenterror-zero-p-p-one-p-is-not-satisfied/37601 "2020-04-17T02:26:33Z")

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Hi All, This is my first post in Julia discourse! I have been trying to do parameter inference in a classical Susceptible-Infected-Recovered epidemic model using Turing. I am finding a strange error: the program correc…

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## [Why cannot Julia v1.4 find the installed Python?](https://discourse.julialang.org/t/why-cannot-julia-v1-4-find-the-installed-python/37726)

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**Author:** [@fhkm](https://discourse.julialang.org/u/fhkm)\
**Replies:** 0\
**Last updated:** [April 17, 2020, 12:17am UTC](https://discourse.julialang.org/t/why-cannot-julia-v1-4-find-the-installed-python/37726 "2020-04-17T00:17:08Z")

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I installed Python V3.8 on windows 7 x64 and would like to rebuild PyCall. I added PyCall package. I changed the global variable ENV ENV\[“PYTHON”\] = “D:\\programs\\python\\v38\\python.exe” Then I use the command usin…

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## [Unsafe\_wrap C pointer after first element](https://discourse.julialang.org/t/unsafe-wrap-c-pointer-after-first-element/37723)

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**Author:** [@joa-quim](https://discourse.julialang.org/u/joa-quim)\
**Replies:** 4\
**Last updated:** [April 17, 2020, 12:37am UTC](https://discourse.julialang.org/t/unsafe-wrap-c-pointer-after-first-element/37723 "2020-04-17T00:37:31Z")

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Hi, How to wrap the contents of a C pointer, not from its first element, which is done with unsafe\_wrap(Array, ptr, 100) but for example, from its 50th element? With C address it would be unsafe\_wrap(Array, &ptr\[49\]…

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## [Plot using @timed](https://discourse.julialang.org/t/plot-using-timed/37714)

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**Author:** [@A.U.M](https://discourse.julialang.org/u/A.U.M)\
**Replies:** 3\
**Last updated:** [April 16, 2020, 10:48pm UTC](https://discourse.julialang.org/t/plot-using-timed/37714 "2020-04-16T22:48:40Z")

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I have implemented three functions to calculate the Fibonacci numbers like the following: function fib(n::Integer)::BigInt if n \<= 1 n else fib(n-1) + fib(n-2) end end \*\* fib2(n::Integer)::BigInt =round(BigInt,((1+sqr…

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## [Any suggestions for starting doing this kind of neighbour list?](https://discourse.julialang.org/t/any-suggestions-for-starting-doing-this-kind-of-neighbour-list/37436)

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**Author:** [@Ahmed\_Salih](https://discourse.julialang.org/u/Ahmed_Salih)\
**Replies:** 12\
**Last updated:** [April 16, 2020, 9:59pm UTC](https://discourse.julialang.org/t/any-suggestions-for-starting-doing-this-kind-of-neighbour-list/37436 "2020-04-16T21:59:37Z")

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Hello! I am trying to make a neighbour list like this, where one has N number of particles. Overlayed on top of these particles is a square grid with equal sizes. The goal is then output a structure/array/something else…

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## [How to access the data in @timed and plot directly](https://discourse.julialang.org/t/how-to-access-the-data-in-timed-and-plot-directly/37692)

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**Author:** [@A.U.M](https://discourse.julialang.org/u/A.U.M)\
**Replies:** 0\
**Last updated:** [April 16, 2020, 10:24am UTC](https://discourse.julialang.org/t/how-to-access-the-data-in-timed-and-plot-directly/37692 "2020-04-16T10:24:02Z")

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I have implemented three functions to calculate the Fibonacci numbers like the following: function fib(n::Integer)::BigInt if n \<= 1 n else fib(n-1) + fib(n-2) end end \*\* fib2(n::Integer)::BigInt =round(BigInt,((1+sqr…

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## [How do I create a new Array-like type with only ints and strings?](https://discourse.julialang.org/t/how-do-i-create-a-new-array-like-type-with-only-ints-and-strings/37711)

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**Author:** [@Alex\_Tantos](https://discourse.julialang.org/u/Alex_Tantos)\
**Replies:** 8\
**Last updated:** [April 16, 2020, 7:13pm UTC](https://discourse.julialang.org/t/how-do-i-create-a-new-array-like-type-with-only-ints-and-strings/37711 "2020-04-16T19:13:32Z")

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Hi there! As am heading towards understanding the type system of Julia, I seem to not be able to do such a thing as to create-define a container type that would include only strings and integers. Could anyone drop me t…

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## [Table zebra stripes using Documenter.jl](https://discourse.julialang.org/t/table-zebra-stripes-using-documenter-jl/37707)

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**Author:** [@Mirsad\_Cosovic](https://discourse.julialang.org/u/Mirsad_Cosovic)\
**Replies:** 3\
**Last updated:** [April 16, 2020, 7:01pm UTC](https://discourse.julialang.org/t/table-zebra-stripes-using-documenter-jl/37707 "2020-04-16T19:01:08Z")

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Hi, I’m curious how to make tables with zebra stripes, using Documenter and Github Actions, like here: http://gadflyjl.org/stable/man/plotting/

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## [CUDA gradient of gamma PDF](https://discourse.julialang.org/t/cuda-gradient-of-gamma-pdf/37431)

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**Author:** [@clinton](https://discourse.julialang.org/u/clinton)\
**Replies:** 4\
**Last updated:** [April 15, 2020, 11:36pm UTC](https://discourse.julialang.org/t/cuda-gradient-of-gamma-pdf/37431 "2020-04-15T23:36:13Z")

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I’m having trouble computing an AD gradient of the gamma PDF using a gpu array. The goal is to use this as part of a Flux project. I am happy to open an issue, but I am new enough to gpu coding that I want to make sure I…

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## [Error when compile v1.4.0](https://discourse.julialang.org/t/error-when-compile-v1-4-0/37700)

<div class="topic-metadata">

**Author:** [@Zhang\_Wei](https://discourse.julialang.org/u/Zhang_Wei)\
**Replies:** 5\
**Last updated:** [April 16, 2020, 5:37pm UTC](https://discourse.julialang.org/t/error-when-compile-v1-4-0/37700 "2020-04-16T17:37:30Z")

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Hi All, I try to compile v1.4.0 using gcc 6.4.0, get following error: error during bootstrap: LoadError(“sysimg.jl”, 3, LoadError(“Base.jl”, 198, LoadError(“version.jl”, 240, ArgumentError("invalid version string: ")…

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## [Questions about Julialang: The Ingredients for a Composable Programming Language](https://discourse.julialang.org/t/questions-about-julialang-the-ingredients-for-a-composable-programming-language/37646)

<div class="topic-metadata">

**Author:** [@xiaodai](https://discourse.julialang.org/u/xiaodai)\
**Replies:** 2\
**Last updated:** [April 16, 2020, 5:29pm UTC](https://discourse.julialang.org/t/questions-about-julialang-the-ingredients-for-a-composable-programming-language/37646 "2020-04-16T17:29:47Z")

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I read this article from @oxinabox with great interest and it’s a great article (and talk) https://t.co/AdeHABesNW?amp=1 One point that I found very interesting was that Open classes: so you can create new methods …

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