# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=381

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**Page:** 382

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## [Makie stopped working on my machine after update](https://discourse.julialang.org/t/makie-stopped-working-on-my-machine-after-update/57392)

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**Author:** [@tt1234567](https://discourse.julialang.org/u/tt1234567)\
**Replies:** 11\
**Last updated:** [March 17, 2021, 4:56pm UTC](https://discourse.julialang.org/t/makie-stopped-working-on-my-machine-after-update/57392 "2021-03-17T16:56:15Z")

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Hello I did a package update this morning and Makie seems to have stopped working. I tried deleting the .julia directory and instantiating again but the problem didn’t change. Is it just me? using Makie fig = Makie.Fig…

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## [Read complex text files in Julia](https://discourse.julialang.org/t/read-complex-text-files-in-julia/57386)

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**Author:** [@baprata](https://discourse.julialang.org/u/baprata)\
**Replies:** 4\
**Last updated:** [March 17, 2021, 4:13pm UTC](https://discourse.julialang.org/t/read-complex-text-files-in-julia/57386 "2021-03-17T16:13:50Z")

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I need to read this file (https://drive.google.com/file/d/1VSVxE7tMFutzNZhVmhsFnoSgCnpFZAUL/view?usp=sharing) to obtain a matrix and a vector as follows. Could anybody helps me? Array (20 x 5): 1 4 87 21 28 68 3…

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## [Frequency Weights in DataFrames](https://discourse.julialang.org/t/frequency-weights-in-dataframes/57379)

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**Author:** [@drarnau](https://discourse.julialang.org/u/drarnau)\
**Replies:** 2\
**Last updated:** [March 17, 2021, 1:31pm UTC](https://discourse.julialang.org/t/frequency-weights-in-dataframes/57379 "2021-03-17T13:31:26Z")

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Hello, I need to compute a group mean using frequency weights and I do not know how to do it. I know how to compute an un weighted mean: using DataFrames df = DataFrame(age = rand(25:30, 25), value = rand(25), fweigh…

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## [Writing file inside a loop](https://discourse.julialang.org/t/writing-file-inside-a-loop/57376)

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**Author:** [@ccmejia](https://discourse.julialang.org/u/ccmejia)\
**Replies:** 4\
**Last updated:** [March 17, 2021, 1:18pm UTC](https://discourse.julialang.org/t/writing-file-inside-a-loop/57376 "2021-03-17T13:18:15Z")

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Hi there! I’m running some stuff in a cluster… Due to this take long time calculations I would like to follow some kind of output file to know how it is going… It seems that inside a loop the output file is not modified…

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## [Plots.jl: arrows style in quiver()?](https://discourse.julialang.org/t/plots-jl-arrows-style-in-quiver/13659)

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**Author:** [@wrgr](https://discourse.julialang.org/u/wrgr)\
**Replies:** 7\
**Last updated:** [March 17, 2021, 7:08am UTC](https://discourse.julialang.org/t/plots-jl-arrows-style-in-quiver/13659 "2021-03-17T07:08:08Z")

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In Plots.jl, quiver(x, y, gradient=(u, v), ...) produces arrows with head sizes being independent of gradient magnitude, like this: The vector in the bottom-left corner has a small norm, and its head looks dispropor…

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## [Passing objective function into JuMP](https://discourse.julialang.org/t/passing-objective-function-into-jump/57357)

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**Author:** [@samerb](https://discourse.julialang.org/u/samerb)\
**Replies:** 1\
**Last updated:** [March 17, 2021, 4:29am UTC](https://discourse.julialang.org/t/passing-objective-function-into-jump/57357 "2021-03-17T04:29:19Z")

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I would like to use JuMP for nonlinear constrained optimization. Specifically I want to be able to pass my objective function into it from outside. How do I do that? What I tried is below. I am not sure if this is a JuM…

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## [GeometricFlux.jl - Is there a true variable graph layer?](https://discourse.julialang.org/t/geometricflux-jl-is-there-a-true-variable-graph-layer/57225)

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**Author:** [@emsal](https://discourse.julialang.org/u/emsal)\
**Replies:** 5\
**Last updated:** [March 17, 2021, 2:59am UTC](https://discourse.julialang.org/t/geometricflux-jl-is-there-a-true-variable-graph-layer/57225 "2021-03-17T02:59:40Z")

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I’m looking into using https://github.com/yuehhua/GeometricFlux.jl. I notice that as per docs page https://yuehhua.github.io/GeometricFlux.jl/dev/basics/passgraph/, to pass a variable graph you need to define the GCNConv …

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## [Invalid Gurobi license](https://discourse.julialang.org/t/invalid-gurobi-license/57324)

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**Author:** [@Yaropro14](https://discourse.julialang.org/u/Yaropro14)\
**Replies:** 2\
**Last updated:** [March 16, 2021, 8:32pm UTC](https://discourse.julialang.org/t/invalid-gurobi-license/57324 "2021-03-16T20:32:13Z")

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After ENV\[“GRB\_LICENSE\_FILE”\] = “/Library/gurobi911” ENV\[“GUROBI\_HOME”\] = “/Library/gurobi911/mac64/” import Pkg Pkg.rm(“Gurobi”) Pkg.add(“Gurobi”) Pkg.build(“Gurobi”) using Gurobi const GUROBI\_ENV = Gurobi.Env() …

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## [ModelingToolkit.jl cryptic error](https://discourse.julialang.org/t/modelingtoolkit-jl-cryptic-error/57308)

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**Author:** [@ohmsweetohm1](https://discourse.julialang.org/u/ohmsweetohm1)\
**Replies:** 3\
**Last updated:** [March 16, 2021, 7:38pm UTC](https://discourse.julialang.org/t/modelingtoolkit-jl-cryptic-error/57308 "2021-03-16T19:38:35Z")

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I was trying to model a thermo-fluid system with ModelingToolkit.jl, however I encountered this: julia\> prob = ODAEProblem(sys, Pair\[\], (0.0, 10.0)) ERROR: AssertionError: !(isalgvar(s, var)) What does it mean? Th…

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## [Help with using the Plots package](https://discourse.julialang.org/t/help-with-using-the-plots-package/57036)

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**Author:** [@RaquelSantos](https://discourse.julialang.org/u/RaquelSantos)\
**Replies:** 22\
**Last updated:** [March 16, 2021, 6:55pm UTC](https://discourse.julialang.org/t/help-with-using-the-plots-package/57036 "2021-03-16T18:55:10Z")

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Hello How to plot a two-dimensional graph? In this example I am trying to plot (x, y) and in response Julia returns a three-dimensional graph. using Plots x = 1:4 y = \[0.16, 12, 8, 0.13\] y1 = \[0.07, 13, 7\] y2 = y,y1 p…

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## [\[ANN\] Arrow.jl 0.3 Release](https://discourse.julialang.org/t/ann-arrow-jl-0-3-release/47727)

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**Author:** [@quinnj](https://discourse.julialang.org/u/quinnj)\
**Replies:** 21\
**Last updated:** [March 16, 2021, 5:53pm UTC](https://discourse.julialang.org/t/ann-arrow-jl-0-3-release/47727 "2021-03-16T17:53:27Z")

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A new 0.3 release has just been made for the Arrow.jl package. This is a significant rewrite of the entire package from scratch, and it now lives under the JuliaData organization. With this release, Arrow.jl now fully i…

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## [Matrix shortest distance problem - Need suggestions to improve the performance](https://discourse.julialang.org/t/matrix-shortest-distance-problem-need-suggestions-to-improve-the-performance/57175)

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**Author:** [@shanmukhan](https://discourse.julialang.org/u/shanmukhan)\
**Replies:** 27\
**Last updated:** [March 16, 2021, 3:25pm UTC](https://discourse.julialang.org/t/matrix-shortest-distance-problem-need-suggestions-to-improve-the-performance/57175 "2021-03-16T15:25:55Z")

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Hello All, I am new to Julia and working on below code in Julia and similar one in Python, Java. But, Julia code is slower than Python and 10x slower than Java code. Can you please let me know how to optimize below code…

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## [How to run Julia on Cluster?](https://discourse.julialang.org/t/how-to-run-julia-on-cluster/56551)

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**Author:** [@Shazman](https://discourse.julialang.org/u/Shazman)\
**Replies:** 11\
**Last updated:** [March 16, 2021, 1:34pm UTC](https://discourse.julialang.org/t/how-to-run-julia-on-cluster/56551 "2021-03-16T13:34:48Z")

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Hi, I am trying to run Julia on the Cluster. the main problem for me is to write the job script to tell the cluster to run my Julia commands. the cluster is using Slurm. anyone have an idea how to do it?

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## [QR Parameterization in Turing](https://discourse.julialang.org/t/qr-parameterization-in-turing/57203)

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**Author:** [@Storopoli](https://discourse.julialang.org/u/Storopoli)\
**Replies:** 2\
**Last updated:** [March 16, 2021, 8:19am UTC](https://discourse.julialang.org/t/qr-parameterization-in-turing/57203 "2021-03-16T08:19:41Z")

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A question to Turing Specialists. I performed a QR decomposition on my model matrix X. #### QR Decomposition #### Q, R = qr(X) Then i fitted a Turing Model to my Q Matrix, casting it to a Matrix: model\_qr = varying\_i…

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## [Celltracker possibilities?](https://discourse.julialang.org/t/celltracker-possibilities/46736)

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**Author:** [@ervern](https://discourse.julialang.org/u/ervern)\
**Replies:** 11\
**Last updated:** [March 16, 2021, 7:31am UTC](https://discourse.julialang.org/t/celltracker-possibilities/46736 "2021-03-16T07:31:35Z")

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Hi im a student and was wondering if this would be a good language to make a program that tracks cells in a video rather than python or MATLAB. If so I was wondering where I should start. Thanks!

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## [Library for 3D model simulation visualization](https://discourse.julialang.org/t/library-for-3d-model-simulation-visualization/57237)

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**Author:** [@AlexS12](https://discourse.julialang.org/u/AlexS12)\
**Replies:** 2\
**Last updated:** [March 15, 2021, 11:44pm UTC](https://discourse.julialang.org/t/library-for-3d-model-simulation-visualization/57237 "2021-03-15T23:44:33Z")

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I have seen this post with a matlab example that I would like to emulate in Julia. As a summary I would like to plot a 3d model loaded from a mesh file (.stl or similar) and rotate it “real time” according to a time seri…

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## [Static matrix equation solve in-place?](https://discourse.julialang.org/t/static-matrix-equation-solve-in-place/57231)

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**Author:** [@markmbaum](https://discourse.julialang.org/u/markmbaum)\
**Replies:** 7\
**Last updated:** [March 15, 2021, 10:38pm UTC](https://discourse.julialang.org/t/static-matrix-equation-solve-in-place/57231 "2021-03-15T22:38:16Z")

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I’m using static arrays to solve a 3x3 matrix equation that has to be solved repeatedly. Is there a function for solving these equations in place with static arrays (SMatrix, SVector)? I see all the in-place BLAS routine…

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## [Automatic generation user-defined functions and NLexpression](https://discourse.julialang.org/t/automatic-generation-user-defined-functions-and-nlexpression/57216)

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**Author:** [@GiuliaM](https://discourse.julialang.org/u/GiuliaM)\
**Replies:** 1\
**Last updated:** [March 15, 2021, 7:42pm UTC](https://discourse.julialang.org/t/automatic-generation-user-defined-functions-and-nlexpression/57216 "2021-03-15T19:42:25Z")

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Hi everyone! I’m trying to create a non-linear expression for a non-linear problem. I need to automatically register some user-defined functions (in the MWE func1 and func2) and use them in the NLexpression. In partic…

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## [State of Signals](https://discourse.julialang.org/t/state-of-signals/9495)

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**Author:** [@Raf](https://discourse.julialang.org/u/Raf)\
**Replies:** 7\
**Last updated:** [March 15, 2021, 4:19pm UTC](https://discourse.julialang.org/t/state-of-signals/9495 "2021-03-15T16:19:19Z")

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There are a lot of packages for signals these days: https://github.com/JuliaGizmos/Reactive.jl https://github.com/JuliaGizmos/Observables.jl https://github.com/TsurHerman/Signals.jl https://github.com/tshort/Reactive…

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## [ModelingToolkit.jl hydraulic model](https://discourse.julialang.org/t/modelingtoolkit-jl-hydraulic-model/57084)

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**Author:** [@ohmsweetohm1](https://discourse.julialang.org/u/ohmsweetohm1)\
**Replies:** 8\
**Last updated:** [March 15, 2021, 3:36pm UTC](https://discourse.julialang.org/t/modelingtoolkit-jl-hydraulic-model/57084 "2021-03-15T15:36:49Z")

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@ChrisRackauckas Thx for ModelingToolkit.jl I really like it! I tried to model a simple hydraulic system. However, I soon ran into some problems. Consider the following example (adaptation of the RC example): using Mo…

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## [Parallelizing Loss Function](https://discourse.julialang.org/t/parallelizing-loss-function/57035)

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**Author:** [@Honza9723](https://discourse.julialang.org/u/Honza9723)\
**Replies:** 4\
**Last updated:** [March 15, 2021, 2:40pm UTC](https://discourse.julialang.org/t/parallelizing-loss-function/57035 "2021-03-15T14:40:51Z")

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Dear All, I would like to ask you for advice regarding how to parallelize the loss function in Flux. Context: I am solving a discounted infinite-horizon optimization problem (in economics). It has three controls (Cs, Ci…

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## [Sorting a sparse axis array in JuMP](https://discourse.julialang.org/t/sorting-a-sparse-axis-array-in-jump/57167)

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**Author:** [@priod](https://discourse.julialang.org/u/priod)\
**Replies:** 3\
**Last updated:** [March 15, 2021, 7:23am UTC](https://discourse.julialang.org/t/sorting-a-sparse-axis-array-in-jump/57167 "2021-03-15T07:23:41Z")

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Hi, I am using the JuMP model, after the optimization process, I have a sparse axis array, I need to sort this array in the descending direction. How can I sort this? Thanking you in advance for the suggestions. The…

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## [GPU gradient issues with matrix tranpose](https://discourse.julialang.org/t/gpu-gradient-issues-with-matrix-tranpose/57145)

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**Author:** [@JLDC](https://discourse.julialang.org/u/JLDC)\
**Replies:** 0\
**Last updated:** [March 14, 2021, 7:23pm UTC](https://discourse.julialang.org/t/gpu-gradient-issues-with-matrix-tranpose/57145 "2021-03-14T19:23:56Z")

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Hello, I recently stumbled upon the following issue: using Flux m = Chain( Dense(100, 10, relu), Dense(10, 10)) |\> gpu s = (X = gpu(rand(100)), k = 0.99, y = gpu(rand(10))) # Works fine gs = gradient(() -\> log(s.k \*…

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## [Is there an reinforcement learning gym like OpenAI provides?](https://discourse.julialang.org/t/is-there-an-reinforcement-learning-gym-like-openai-provides/57132)

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**Author:** [@LarkyJulia](https://discourse.julialang.org/u/LarkyJulia)\
**Replies:** 2\
**Last updated:** [March 14, 2021, 5:57pm UTC](https://discourse.julialang.org/t/is-there-an-reinforcement-learning-gym-like-openai-provides/57132 "2021-03-14T17:57:20Z")

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If yes, is it a native Julia library? Thanks.

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## [Current advice on stacked bar plots with Makie](https://discourse.julialang.org/t/current-advice-on-stacked-bar-plots-with-makie/57095)

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**Author:** [@kevbonham](https://discourse.julialang.org/u/kevbonham)\
**Replies:** 2\
**Last updated:** [March 14, 2021, 1:52am UTC](https://discourse.julialang.org/t/current-advice-on-stacked-bar-plots-with-makie/57095 "2021-03-14T01:52:41Z")

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This functionality used to reside in StatsMakie, but AlgebraOfGraphics doesn’t seem to have it. I also can’t find it in the base Makie docs. In StatsPlots, this would be: julia\> using DataFrames, StatsPlots julia\> df …

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## [Julia on Slurm Cluster](https://discourse.julialang.org/t/julia-on-slurm-cluster/57090)

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**Author:** [@Shazman](https://discourse.julialang.org/u/Shazman)\
**Replies:** 5\
**Last updated:** [March 13, 2021, 8:40pm UTC](https://discourse.julialang.org/t/julia-on-slurm-cluster/57090 "2021-03-13T20:40:05Z")

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Hi, I am trying to run Julia on SlurmCluster, my data is in my current directory on the Cluster. the julia code Id like to run (main.jl) using DelimitedFiles mme = readdlm(“mme.txt”) rhs = readdlm(“rhs.txt”) b = …

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## [Sampling with replacement on GPU](https://discourse.julialang.org/t/sampling-with-replacement-on-gpu/56121)

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**Author:** [@simsurace](https://discourse.julialang.org/u/simsurace)\
**Replies:** 5\
**Last updated:** [March 13, 2021, 8:05pm UTC](https://discourse.julialang.org/t/sampling-with-replacement-on-gpu/56121 "2021-03-13T20:05:51Z")

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I have a CuArray with weights, i.e. each row is a weight vector (not necessarily normalized but this is easy to accomplish if needed). I want to draw number\_of\_column numbers in 1:number\_of\_columns for each of the rows i…

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## [Plots with a secondary, non-linear, axis scale](https://discourse.julialang.org/t/plots-with-a-secondary-non-linear-axis-scale/56661)

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**Author:** [@rafael.guerra](https://discourse.julialang.org/u/rafael.guerra)\
**Replies:** 3\
**Last updated:** [March 13, 2021, 5:21pm UTC](https://discourse.julialang.org/t/plots-with-a-secondary-non-linear-axis-scale/56661 "2021-03-13T17:21:01Z")

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Based on this stack overflow post, a non-linear invertible function can be used to define a secondary PyPlot axis scale. Two questions, if you will: (1) Is it possible to do this with other plot backends? (2) If inst…

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## [Categorical heatmap](https://discourse.julialang.org/t/categorical-heatmap/56931)

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**Author:** [@jzr](https://discourse.julialang.org/u/jzr)\
**Replies:** 4\
**Last updated:** [March 12, 2021, 11:19am UTC](https://discourse.julialang.org/t/categorical-heatmap/56931 "2021-03-12T11:19:58Z")

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Can I use AoG for a categorical heatmap? using RDatasets let diamonds = dataset("ggplot2", "diamonds") p = data(diamonds) \* mapping(:Cut =\> categorical, :Color =\> categorical, color=:Price) \* visual(Heatmap) draw(…

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## [Reapply groupby on a GroupedDataFrame](https://discourse.julialang.org/t/reapply-groupby-on-a-groupeddataframe/57046)

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**Author:** [@jeremiedb](https://discourse.julialang.org/u/jeremiedb)\
**Replies:** 2\
**Last updated:** [March 12, 2021, 10:39pm UTC](https://discourse.julialang.org/t/reapply-groupby-on-a-groupeddataframe/57046 "2021-03-12T22:39:30Z")

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Is there a reason for groupby not supporting a GroupedDataFrame as an input? In a use case, if I try to apply a transform base on different groups, it will hit an error: dfg = groupby(df, "eid") transform!(dfg, "amount…

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