# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1280

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

**Page:** 1281

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## [Recommended serialization for distributed file systems (and is old jld2 data gone forever)?](https://discourse.julialang.org/t/recommended-serialization-for-distributed-file-systems-and-is-old-jld2-data-gone-forever/65759)

<div class="topic-metadata">

**Author:** [@mkarikom](https://discourse.julialang.org/u/mkarikom)\
**Replies:** 1\
**Last updated:** [August 31, 2021, 3:09pm UTC](https://discourse.julialang.org/t/recommended-serialization-for-distributed-file-systems-and-is-old-jld2-data-gone-forever/65759 "2021-08-31T15:09:14Z")

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I’m trying to read .jld2 files from a cluster dfs share and keep getting stuff like: BoundsError: attempt to access 23-element Vector{Int64} at index \[31\] Stacktrace: \[1\] getindex @ ./array.jl:801 \[inlined\] \[2\] …

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## [Context menu in Makie?](https://discourse.julialang.org/t/context-menu-in-makie/66728)

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**Author:** [@RainerHeintzmann](https://discourse.julialang.org/u/RainerHeintzmann)\
**Replies:** 10\
**Last updated:** [August 31, 2021, 2:44pm UTC](https://discourse.julialang.org/t/context-menu-in-makie/66728 "2021-08-31T14:44:59Z")

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Does Makie support context menus, e.g. reachable by right clicking into a view that is covered by a particular axis? This would be a great feature.

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## [Converting a directed graph to undirected](https://discourse.julialang.org/t/converting-a-directed-graph-to-undirected/66932)

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**Author:** [@rachithaiyappa](https://discourse.julialang.org/u/rachithaiyappa)\
**Replies:** 4\
**Last updated:** [August 31, 2021, 2:16pm UTC](https://discourse.julialang.org/t/converting-a-directed-graph-to-undirected/66932 "2021-08-31T14:16:16Z")

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I am reading a graph from an edge list and then trying to convert the directed graph into undirected as follows. using GraphIO using SimpleGraphs data = "network.txt" #edge list of the network g = loadgraph(data,GraphI…

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## [Can fields of structure be indexed by number?](https://discourse.julialang.org/t/can-fields-of-structure-be-indexed-by-number/67423)

<div class="topic-metadata">

**Author:** [@Amro](https://discourse.julialang.org/u/Amro)\
**Replies:** 6\
**Last updated:** [August 31, 2021, 1:47pm UTC](https://discourse.julialang.org/t/can-fields-of-structure-be-indexed-by-number/67423 "2021-08-31T13:47:26Z")

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It is know that accessing a field of structure is by using the dot method. Such as, accessing the first field of the below structure is Point.x. However, I would like to access the fields by using a index number accompan…

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## [How to initialize empty dataframe of specified size](https://discourse.julialang.org/t/how-to-initialize-empty-dataframe-of-specified-size/67421)

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**Author:** [@Cevheriferd](https://discourse.julialang.org/u/Cevheriferd)\
**Replies:** 4\
**Last updated:** [August 31, 2021, 1:16pm UTC](https://discourse.julialang.org/t/how-to-initialize-empty-dataframe-of-specified-size/67421 "2021-08-31T13:16:23Z")

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Hi my question is as stated in the title. So I want to know what is the easiest way to create a dataframe with the column names, the type of the column and the number of rows specified in the beginning. I know you can do…

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## [Unhexlify and int.from\_bytes (From a lazy pythonist to a confused Julia user)](https://discourse.julialang.org/t/unhexlify-and-int-from-bytes-from-a-lazy-pythonist-to-a-confused-julia-user/67388)

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**Author:** [@Mrs.Pelle](https://discourse.julialang.org/u/Mrs.Pelle)\
**Replies:** 6\
**Last updated:** [August 31, 2021, 12:58pm UTC](https://discourse.julialang.org/t/unhexlify-and-int-from-bytes-from-a-lazy-pythonist-to-a-confused-julia-user/67388 "2021-08-31T12:58:32Z")

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So I’m slowly transferring some crypto blockchain programming to Julia and I’m hitting quite a wall with all the whole hashing, bytes, etc etc. So the first one I’m trying to migrate over is the python binascii.unhexlif…

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## [Forwarddiff through setindex](https://discourse.julialang.org/t/forwarddiff-through-setindex/67422)

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**Author:** [@weymouth](https://discourse.julialang.org/u/weymouth)\
**Replies:** 1\
**Last updated:** [August 31, 2021, 12:38pm UTC](https://discourse.julialang.org/t/forwarddiff-through-setindex/67422 "2021-08-31T12:38:07Z")

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I’m having trouble differentiating through the setindex!() of a custom type. Here’s a minimum example using the ArrayAndChar type from the Julia docs to replicate the issue. using ForwardDiff struct ArrayAndChar{T,N} \<…

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## [Can Symbolics.jl simplify subexpressions?](https://discourse.julialang.org/t/can-symbolics-jl-simplify-subexpressions/66731)

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**Author:** [@nhardy](https://discourse.julialang.org/u/nhardy)\
**Replies:** 6\
**Last updated:** [August 31, 2021, 12:41pm UTC](https://discourse.julialang.org/t/can-symbolics-jl-simplify-subexpressions/66731 "2021-08-31T12:41:29Z")

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I have been trying out Symbolics.jl for a few projects recently. Initially I was excited but have run into a few issues that are road blocks. Some are probably asking too much this early in development - (A::SparseMatri…

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## [Flux model with \`SubArray\` parameters don't work on GPU](https://discourse.julialang.org/t/flux-model-with-subarray-parameters-dont-work-on-gpu/60401)

<div class="topic-metadata">

**Author:** [@ArthurW](https://discourse.julialang.org/u/ArthurW)\
**Replies:** 4\
**Last updated:** [August 31, 2021, 12:14pm UTC](https://discourse.julialang.org/t/flux-model-with-subarray-parameters-dont-work-on-gpu/60401 "2021-08-31T12:14:14Z")

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Hi everyone, I’m trying to compute the gradient for a “submodel” of a Flux model. That is, I’m defining layers with SubArrays of the original weights as parameters. julia\> using Flux julia\> X = rand(4, 1000) |\> gpu; …

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## [Fuzzy rounding for Rationals](https://discourse.julialang.org/t/fuzzy-rounding-for-rationals/67420)

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**Author:** [@bernhard](https://discourse.julialang.org/u/bernhard)\
**Replies:** 3\
**Last updated:** [August 31, 2021, 11:57am UTC](https://discourse.julialang.org/t/fuzzy-rounding-for-rationals/67420 "2021-08-31T11:57:45Z")

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Is there an easy way to convert 0.005 to a Rational 1//200 ? I guess 0.005 has no exact representation in base 2, which is why it is interpreted as this terribly long fraction. EDIT: Actually my use case is more “gener…

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## [How to understand MapReduce](https://discourse.julialang.org/t/how-to-understand-mapreduce/67418)

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**Author:** [@Jakub\_Mitura](https://discourse.julialang.org/u/Jakub_Mitura)\
**Replies:** 1\
**Last updated:** [August 31, 2021, 11:23am UTC](https://discourse.julialang.org/t/how-to-understand-mapreduce/67418 "2021-08-31T11:23:45Z")

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Hello I am analyzing CUDA.jl mapReduce.jl file and I see two things that I do not understand First I see that function shfl\_down\_sync is avoided when type of data is another than Bool, Int32, Int64, Float32, Float64, …

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## [Makie allocations and speed](https://discourse.julialang.org/t/makie-allocations-and-speed/67376)

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**Author:** [@RainerHeintzmann](https://discourse.julialang.org/u/RainerHeintzmann)\
**Replies:** 4\
**Last updated:** [August 31, 2021, 11:20am UTC](https://discourse.julialang.org/t/makie-allocations-and-speed/67376 "2021-08-31T11:20:14Z")

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Writing a little GUI for visualizing ND data in GLMakie.jl we noted that the allocations are rather high in Makie, which may be one reason that the startup time is significant. The data to visualize is minute (e.g. 2x2x…

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## [Custom coloring function?](https://discourse.julialang.org/t/custom-coloring-function/67417)

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**Author:** [@Sukera](https://discourse.julialang.org/u/Sukera)\
**Replies:** 1\
**Last updated:** [August 31, 2021, 10:46am UTC](https://discourse.julialang.org/t/custom-coloring-function/67417 "2021-08-31T10:46:07Z")

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Hi! I’m trying to plot a function f returning complex values using contour. f has a limited number of possibly returned values, which I’d like to plot with a unique color in the resulting contour plot. I thought I could…

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## [Sensitivity analysis on Non-diagonal noise SDEs](https://discourse.julialang.org/t/sensitivity-analysis-on-non-diagonal-noise-sdes/67413)

<div class="topic-metadata">

**Author:** [@alvestad10](https://discourse.julialang.org/u/alvestad10)\
**Replies:** 1\
**Last updated:** [August 31, 2021, 10:06am UTC](https://discourse.julialang.org/t/sensitivity-analysis-on-non-diagonal-noise-sdes/67413 "2021-08-31T10:06:45Z")

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I am trying to do a parameter optimization of an SDE with non-diagonal constant noise. A simplified version of the implementation is (SDE reduced to the simplest possible version which still have the problem) using Stoc…

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## [Option for changing distance between plot guide and axis](https://discourse.julialang.org/t/option-for-changing-distance-between-plot-guide-and-axis/67416)

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**Author:** [@Torkel](https://discourse.julialang.org/u/Torkel)\
**Replies:** 0\
**Last updated:** [August 31, 2021, 10:06am UTC](https://discourse.julialang.org/t/option-for-changing-distance-between-plot-guide-and-axis/67416 "2021-08-31T10:06:03Z")

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A very simple example of why I am interested in this should explain my problem properly: hill(x,v,K,n) = v\*(x^n)/(x^n+K^n) plot(\[1.,1.\],\[-0.05,0.5\],lw=2,linestyle=:dot,color=:black,label="") plot!(\[0.0,1.\],\[0.5,0.5\],lw=…

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## [Using ChainRules rrule for mutating function to work with Zygote](https://discourse.julialang.org/t/using-chainrules-rrule-for-mutating-function-to-work-with-zygote/67375)

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**Author:** [@mrVeng](https://discourse.julialang.org/u/mrVeng)\
**Replies:** 2\
**Last updated:** [August 31, 2021, 10:03am UTC](https://discourse.julialang.org/t/using-chainrules-rrule-for-mutating-function-to-work-with-zygote/67375 "2021-08-31T10:03:39Z")

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Hi there, I would like to add an rrule for a function that mutates an input array that I want to differentiate with. The following functions can be used with Forward/ReverseDiff, but gives me an Mutation error with Zyg…

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## [Looking for a new PostDoc](https://discourse.julialang.org/t/looking-for-a-new-postdoc/67414)

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**Author:** [@lazarusA](https://discourse.julialang.org/u/lazarusA)\
**Replies:** 0\
**Last updated:** [August 31, 2021, 9:36am UTC](https://discourse.julialang.org/t/looking-for-a-new-postdoc/67414 "2021-08-31T09:36:12Z")

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If you are interested or know somebody that might be, please share. Upcoming deadline! Apply by Sept 15. The Model Data Integration group at the @MPI\_BGC is looking for a new PostDoc!!! Who would like to bridge #Machine…

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## [Postdoctoral Position in Geodynamics / HPC / Julia (ETH Zurich, Switzerland)](https://discourse.julialang.org/t/postdoctoral-position-in-geodynamics-hpc-julia-eth-zurich-switzerland/67410)

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**Author:** [@psanan](https://discourse.julialang.org/u/psanan)\
**Replies:** 0\
**Last updated:** [August 31, 2021, 9:01am UTC](https://discourse.julialang.org/t/postdoctoral-position-in-geodynamics-hpc-julia-eth-zurich-switzerland/67410 "2021-08-31T09:01:43Z")

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We’re looking for a postdoctoral appointee to work on an ambitious project funded by the PASC program. The application areas are large parallel simulations in geodynamics (long-time modelling of the Solid Earth) and ice …

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## [Problem using Differential Equations](https://discourse.julialang.org/t/problem-using-differential-equations/67348)

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**Author:** [@pafloxy](https://discourse.julialang.org/u/pafloxy)\
**Replies:** 10\
**Last updated:** [August 31, 2021, 7:02am UTC](https://discourse.julialang.org/t/problem-using-differential-equations/67348 "2021-08-31T07:02:20Z")

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Hi! 'm trying to get started with Julia for scientific computing. I’m facing a problem in importing the Differential Equations package. The following WARNING pops up~~~~

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## [How to use strings to specify plot axes in VegaLite.jl?](https://discourse.julialang.org/t/how-to-use-strings-to-specify-plot-axes-in-vegalite-jl/67405)

<div class="topic-metadata">

**Author:** [@amrods](https://discourse.julialang.org/u/amrods)\
**Replies:** 2\
**Last updated:** [August 31, 2021, 7:57am UTC](https://discourse.julialang.org/t/how-to-use-strings-to-specify-plot-axes-in-vegalite-jl/67405 "2021-08-31T07:57:40Z")

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How can I use strings to call columns of a DataFrame in VegaLite.jl? using DataFrames using VegaLite df = DataFrame("x" =\> 1:5, "y.α" =\> 1:5) df |\> @vlplot( :line, x = "x", y = "y.α" ) ERROR: LoadError: ArgumentEr…

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## [Build-in markers for 3D scatter](https://discourse.julialang.org/t/build-in-markers-for-3d-scatter/67358)

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**Author:** [@phlavenk](https://discourse.julialang.org/u/phlavenk)\
**Replies:** 2\
**Last updated:** [August 31, 2021, 6:00am UTC](https://discourse.julialang.org/t/build-in-markers-for-3d-scatter/67358 "2021-08-31T06:00:52Z")

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Hi, In a 3D plot I’m trying to combine a semi-transparent mesh (detector body) with a scatter plot of particle hits in its surface (might not lie exactly on the surface, sometimes above or below, depending on the traject…

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## [GLMakie record gives LoadError: IOError: write: broken pipe (EPIPE)](https://discourse.julialang.org/t/glmakie-record-gives-loaderror-ioerror-write-broken-pipe-epipe/64425)

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**Author:** [@bedosh](https://discourse.julialang.org/u/bedosh)\
**Replies:** 5\
**Last updated:** [August 31, 2021, 5:24am UTC](https://discourse.julialang.org/t/glmakie-record-gives-loaderror-ioerror-write-broken-pipe-epipe/64425 "2021-08-31T05:24:30Z")

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I am trying to get GLMakie record to work. Trying the example code from http://makie.juliaplots.org/stable/animation.html: using GLMakie using Makie.Colors fig, ax, lineplot = lines(0..10, sin; linewidth=10) # animat…

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## [Symbolics - Identity matrices for beginners](https://discourse.julialang.org/t/symbolics-identity-matrices-for-beginners/67391)

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**Author:** [@banksiaboy](https://discourse.julialang.org/u/banksiaboy)\
**Replies:** 5\
**Last updated:** [August 31, 2021, 4:50am UTC](https://discourse.julialang.org/t/symbolics-identity-matrices-for-beginners/67391 "2021-08-31T04:50:56Z")

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Hi, I’m trying to relearn linear algebra for the basics of deep-learning. I also want to bootstrap myself into using Symbolics.jl at the same time. I used to enjoy owning MuMath back in the day. I have basic 2 x 2 matr…

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## [Can I change where Julia saves Packages?](https://discourse.julialang.org/t/can-i-change-where-julia-saves-packages/67265)

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**Author:** [@cybervigilante](https://discourse.julialang.org/u/cybervigilante)\
**Replies:** 1\
**Last updated:** [August 29, 2021, 6:24am UTC](https://discourse.julialang.org/t/can-i-change-where-julia-saves-packages/67265 "2021-08-29T06:24:56Z")

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My Windows .julia folder in my home directory is 7 gigs. I assume that’s where all the Packages are going. Is there any way to have Julia save Packages elsewhere since my small laptop’s SSD is getting full? Even Windows …

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## [Converting a BUGS model to Turing, simple linear regression](https://discourse.julialang.org/t/converting-a-bugs-model-to-turing-simple-linear-regression/67340)

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**Author:** [@areding](https://discourse.julialang.org/u/areding)\
**Replies:** 5\
**Last updated:** [August 31, 2021, 2:56am UTC](https://discourse.julialang.org/t/converting-a-bugs-model-to-turing-simple-linear-regression/67340 "2021-08-31T02:56:12Z")

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Hello everyone, I’m thinking about translating a course that focuses on WinBUGS to Turing so the students can use something a little more modern if they want. I’m new to Julia and Turing. Here is the WinBUGS model: fo…

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## [Encapsulating enum access via dot syntax](https://discourse.julialang.org/t/encapsulating-enum-access-via-dot-syntax/11785)

<div class="topic-metadata">

**Author:** [@fbruetting](https://discourse.julialang.org/u/fbruetting)\
**Replies:** 13\
**Last updated:** [August 31, 2021, 2:05am UTC](https://discourse.julialang.org/t/encapsulating-enum-access-via-dot-syntax/11785 "2021-08-31T02:05:01Z")

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Wouldn’t it make sense to access enums via dot syntax, together with maybe/optionally not to pushing all enum members into the scope? I currently have two issues: I am not able to create different enums with the same …

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## [Why am I only seeing one set of colors](https://discourse.julialang.org/t/why-am-i-only-seeing-one-set-of-colors/67386)

<div class="topic-metadata">

**Author:** [@cybervigilante](https://discourse.julialang.org/u/cybervigilante)\
**Replies:** 1\
**Last updated:** [August 31, 2021, 1:31am UTC](https://discourse.julialang.org/t/why-am-i-only-seeing-one-set-of-colors/67386 "2021-08-31T01:31:48Z")

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I thought I would see four different sets of colors, one per second, but I only see the first. Why doesn’t this work? (using Jupyter Lab for Julia in Windows) reshape(\[RGB(rand(),rand(),rand()) for \_ in 1:12\], 4,3) slee…

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## [Using measure in MLJ to evaluate binary classifier](https://discourse.julialang.org/t/using-measure-in-mlj-to-evaluate-binary-classifier/67025)

<div class="topic-metadata">

**Author:** [@Salvatore\_Cosentino](https://discourse.julialang.org/u/Salvatore_Cosentino)\
**Replies:** 2\
**Last updated:** [August 31, 2021, 1:13am UTC](https://discourse.julialang.org/t/using-measure-in-mlj-to-evaluate-binary-classifier/67025 "2021-08-31T01:13:57Z")

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Hello everybody, I am trying to use the measures methods in MLJ to evaluate binary classifications I basically have integer vectors of 0 and 1 for ground truth (gt from now on) and predictions (pred from now on). When…

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## [SystemError for adding new package](https://discourse.julialang.org/t/systemerror-for-adding-new-package/67394)

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**Author:** [@zlq178](https://discourse.julialang.org/u/zlq178)\
**Replies:** 0\
**Last updated:** [August 31, 2021, 1:07am UTC](https://discourse.julialang.org/t/systemerror-for-adding-new-package/67394 "2021-08-31T01:07:45Z")

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I want to add a new package. But it always failed. What is missing?

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## [Confused about how to deploy versions of documentation](https://discourse.julialang.org/t/confused-about-how-to-deploy-versions-of-documentation/67031)

<div class="topic-metadata">

**Author:** [@plafer](https://discourse.julialang.org/u/plafer)\
**Replies:** 2\
**Last updated:** [August 31, 2021, 12:35am UTC](https://discourse.julialang.org/t/confused-about-how-to-deploy-versions-of-documentation/67031 "2021-08-31T00:35:54Z")

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I am confused as to how to deploy my package’s documentation per version. I use Github Actions, and followed the docs for tagbot and documenter.jl, but something still escapes me. Here is my Tagbot config: name: TagBot…

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