# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1376

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

**Page:** 1377

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## [Convert an Array Written as a String to An Actual Array](https://discourse.julialang.org/t/convert-an-array-written-as-a-string-to-an-actual-array/62013)

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**Author:** [@TheCedarPrince](https://discourse.julialang.org/u/TheCedarPrince)\
**Replies:** 7\
**Last updated:** [May 30, 2021, 8:33am UTC](https://discourse.julialang.org/t/convert-an-array-written-as-a-string-to-an-actual-array/62013 "2021-05-30T08:33:06Z")

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Hi all, I have no idea how this happened, but I am using a dataset where in the file, arrays were actually stored as strings like this: "\[1, 2, 3, 4, 5\]" How do I best convert the above into an actual array of integer…

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## [Reverse UnitRange](https://discourse.julialang.org/t/reverse-unitrange/62038)

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**Author:** [@minetest2048](https://discourse.julialang.org/u/minetest2048)\
**Replies:** 3\
**Last updated:** [May 30, 2021, 7:52am UTC](https://discourse.julialang.org/t/reverse-unitrange/62038 "2021-05-30T07:52:11Z")

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I’m trying to implement SystemVerilog style bit indexing/slicing operator: a = 0b11100 b\[4:2\] == 0b111 But I realize that the colon operator doesn’t work when the second index is lower than the first index: julia\> dum…

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## [Looking for advice on achieving faster startup times](https://discourse.julialang.org/t/looking-for-advice-on-achieving-faster-startup-times/61160)

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**Author:** [@enriquer](https://discourse.julialang.org/u/enriquer)\
**Replies:** 11\
**Last updated:** [May 30, 2021, 7:25am UTC](https://discourse.julialang.org/t/looking-for-advice-on-achieving-faster-startup-times/61160 "2021-05-30T07:25:45Z")

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(reposting from a Julia+ARM thread because this is not really ARM specific) I am testing the feasibility of using Julia for an embedded Linux platform. Our current target hardware has a Cortex-A7 based SOC which can run…

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## [DifferentialEquations can solve backward?](https://discourse.julialang.org/t/differentialequations-can-solve-backward/62072)

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**Author:** [@cpraveen](https://discourse.julialang.org/u/cpraveen)\
**Replies:** 1\
**Last updated:** [May 30, 2021, 6:48am UTC](https://discourse.julialang.org/t/differentialequations-can-solve-backward/62072 "2021-05-30T06:48:10Z")

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Using DifferentialEquations, I am solving a simple first order ODE backwards which should work, right ? But the solver fails. I can solve this using my own forward Euler scheme without any problem. Note that the interva…

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## [How can I get a plot for y when I use ACME package](https://discourse.julialang.org/t/how-can-i-get-a-plot-for-y-when-i-use-acme-package/61996)

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**Author:** [@sajad\_ghassemi](https://discourse.julialang.org/u/sajad_ghassemi)\
**Replies:** 5\
**Last updated:** [May 30, 2021, 5:21am UTC](https://discourse.julialang.org/t/how-can-i-get-a-plot-for-y-when-i-use-acme-package/61996 "2021-05-30T05:21:23Z")

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Hello everyone, I am using an example of a ACME.jl package to use for my project in which I should simulate a RLC circuit in Julia, but I don’t know how can I plot y according to time. this is the code which I use from…

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## [PackageCompiler with R](https://discourse.julialang.org/t/packagecompiler-with-r/62069)

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**Author:** [@ParadaCarleton](https://discourse.julialang.org/u/ParadaCarleton)\
**Replies:** 1\
**Last updated:** [May 30, 2021, 2:13am UTC](https://discourse.julialang.org/t/packagecompiler-with-r/62069 "2021-05-30T02:13:24Z")

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I’m interested in reimplementing some R code in Julia to speed it up, then making it a package on CRAN. Is there a way to use PackageCompiler together with JuliaCall to create an R package that uses Julia without requiri…

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## [Easy way to merge a vector into a matrix](https://discourse.julialang.org/t/easy-way-to-merge-a-vector-into-a-matrix/62066)

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**Author:** [@samerb](https://discourse.julialang.org/u/samerb)\
**Replies:** 2\
**Last updated:** [May 30, 2021, 1:26am UTC](https://discourse.julialang.org/t/easy-way-to-merge-a-vector-into-a-matrix/62066 "2021-05-30T01:26:47Z")

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If I have a matrix and a separate column vector, what is the easiest way to merge that column into the matrix? Typically at the front, but potentially at an arbitrary position? This is what I came up with. I had to do t…

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## [Simple addition using Transducers via single-threaded foldl , multi-threaded foldxt always calculates two (slightly) different answers](https://discourse.julialang.org/t/simple-addition-using-transducers-via-single-threaded-foldl-multi-threaded-foldxt-always-calculates-two-slightly-different-answers/62024)

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**Author:** [@Marc.Cox](https://discourse.julialang.org/u/Marc.Cox)\
**Replies:** 4\
**Last updated:** [May 29, 2021, 10:29pm UTC](https://discourse.julialang.org/t/simple-addition-using-transducers-via-single-threaded-foldl-multi-threaded-foldxt-always-calculates-two-slightly-different-answers/62024 "2021-05-29T22:29:21Z")

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Simple addition using Transducers via single-threaded foldl , multi-threaded foldxt calculates two (slightly) different answers . IOW Is the single-threaded foldl , multi-threaded foldxt, or None of them correct ? Some…

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## [Flux score worse than Keras regression... am I doing something wrong?](https://discourse.julialang.org/t/flux-score-worse-than-keras-regression-am-i-doing-something-wrong/61850)

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**Author:** [@shawngiese](https://discourse.julialang.org/u/shawngiese)\
**Replies:** 1\
**Last updated:** [May 29, 2021, 7:36pm UTC](https://discourse.julialang.org/t/flux-score-worse-than-keras-regression-am-i-doing-something-wrong/61850 "2021-05-29T19:36:38Z")

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Hi, I am learning how to work with Keras and Python but I want to try using Julia too. One of the early tests I made was using Keras to make a regression to predict a number. Does anyone have suggestions on what I could …

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## [How resolve compatibility with InteractiveDynamics package?](https://discourse.julialang.org/t/how-resolve-compatibility-with-interactivedynamics-package/62014)

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**Author:** [@murrayE](https://discourse.julialang.org/u/murrayE)\
**Replies:** 6\
**Last updated:** [May 29, 2021, 6:56pm UTC](https://discourse.julialang.org/t/how-resolve-compatibility-with-interactivedynamics-package/62014 "2021-05-29T18:56:11Z")

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I’m a new Julia programmer and want to use the InteractiveDynamics package. But when I try to add it, I get the following error report. How can I resolve this? @v1.6) pkg\> add InteractiveDynamics Resolving package ve…

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## [Array of Dict to array of String](https://discourse.julialang.org/t/array-of-dict-to-array-of-string/61979)

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**Author:** [@Laco\_Kovac](https://discourse.julialang.org/u/Laco_Kovac)\
**Replies:** 5\
**Last updated:** [May 29, 2021, 5:20pm UTC](https://discourse.julialang.org/t/array-of-dict-to-array-of-string/61979 "2021-05-29T17:20:53Z")

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Having array of Dict, e.g. x1 = \[Dict("a"=\>"a", "b"=\>"b", "c"=\>"c"), Dict("a"=\>"e", "b"=\>"f", "c"=\>"g"), Dict("a"=\>"h", "b"=\>"i", "c"=\>"j")\] What would be the most efficient way to convert it to array of strings consis…

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## [How to create a DataFrame from 1×24×24 Array{Float64, 3}](https://discourse.julialang.org/t/how-to-create-a-dataframe-from-1x24x24-array-float64-3/62041)

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**Author:** [@VivMendes](https://discourse.julialang.org/u/VivMendes)\
**Replies:** 4\
**Last updated:** [May 29, 2021, 4:53pm UTC](https://discourse.julialang.org/t/how-to-create-a-dataframe-from-1x24x24-array-float64-3/62041 "2021-05-29T16:53:25Z")

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Hi. I have a matrix named “cycles” which is a 72×24 Matrix{Float64}. I want to obtain a cross-correlation matrix associated with its 24 columns. No problem with this: Cross\_Corr\_matrix = crosscor(cycles\[:,:\],cycles\[:,:\]…

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## [Possible performance drop when using more than one socket threads](https://discourse.julialang.org/t/possible-performance-drop-when-using-more-than-one-socket-threads/62022)

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**Author:** [@shipengcheng1230](https://discourse.julialang.org/u/shipengcheng1230)\
**Replies:** 2\
**Last updated:** [May 29, 2021, 4:50pm UTC](https://discourse.julialang.org/t/possible-performance-drop-when-using-more-than-one-socket-threads/62022 "2021-05-29T16:50:51Z")

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Hello, this is originally raised in an issue. I hope posting here would bring more attention. Some dummy code for solving ODE: # Julia 1.6.1 using FFTW, BenchmarkTools, LinearAlgebra, Printf, Polyester, Random println…

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## [How use Systems.henonheiles from InteractiveDynamics](https://discourse.julialang.org/t/how-use-systems-henonheiles-from-interactivedynamics/62042)

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**Author:** [@murrayE](https://discourse.julialang.org/u/murrayE)\
**Replies:** 0\
**Last updated:** [May 29, 2021, 3:23pm UTC](https://discourse.julialang.org/t/how-use-systems-henonheiles-from-interactivedynamics/62042 "2021-05-29T15:23:49Z")

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I’m trying to duplicate the first example of trajectory evolution in the docs for the InteractiveDynamcis package (https://juliadynamics.github.io/InteractiveDynamics.jl/dev/trajectory/). I’ve already created an environ…

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## [Behaviour of Symbolics.solve\_for](https://discourse.julialang.org/t/behaviour-of-symbolics-solve-for/62019)

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**Author:** [@EvoArt](https://discourse.julialang.org/u/EvoArt)\
**Replies:** 4\
**Last updated:** [May 29, 2021, 3:07pm UTC](https://discourse.julialang.org/t/behaviour-of-symbolics-solve-for/62019 "2021-05-29T15:07:21Z")

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I’ve just started using Symbolics, and I really like it. However, I’m not sure about the output from solve\_for using Symbolics @variables p x y eq = x \*p + y \* (1 - p) ~0 Symbolics.solve\_for(eq,p) returns (p\*y + y\*(1 …

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## [Running TemporalGPs/Stheno sampling](https://discourse.julialang.org/t/running-temporalgps-stheno-sampling/59780)

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**Author:** [@jzr](https://discourse.julialang.org/u/jzr)\
**Replies:** 25\
**Last updated:** [May 29, 2021, 2:14pm UTC](https://discourse.julialang.org/t/running-temporalgps-stheno-sampling/59780 "2021-05-29T14:14:19Z")

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I want to try sampling with TemporalGPs because it may be faster on larger data, as mentioned in another thread. The docs say to use Stheno’s examples for reference so I tried that. I had some issues and questions: II…

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## [Should we have a package update PSA?](https://discourse.julialang.org/t/should-we-have-a-package-update-psa/61923)

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**Author:** [@nilshg](https://discourse.julialang.org/u/nilshg)\
**Replies:** 8\
**Last updated:** [May 29, 2021, 9:57am UTC](https://discourse.julialang.org/t/should-we-have-a-package-update-psa/61923 "2021-05-29T09:57:07Z")

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I’ve been tinkering with the idea of writing this for a while but never got around to it, so I’ll at least put the idea here in case anyone agrees and wants to make a start. I believe over the last few months the most fr…

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## [Automatically activating project on remote workers](https://discourse.julialang.org/t/automatically-activating-project-on-remote-workers/62034)

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**Author:** [@jishnub](https://discourse.julialang.org/u/jishnub)\
**Replies:** 1\
**Last updated:** [May 29, 2021, 8:27am UTC](https://discourse.julialang.org/t/automatically-activating-project-on-remote-workers/62034 "2021-05-29T08:27:03Z")

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Starting Julia with multiple workers and an active project currently only activates the environment on the master process. Does it not make more sense to activate the project on all workers? jishnu:OffsetArrays.jl/ $ ju…

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## [Return Tuple from JuMP](https://discourse.julialang.org/t/return-tuple-from-jump/62026)

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**Author:** [@mjanun](https://discourse.julialang.org/u/mjanun)\
**Replies:** 3\
**Last updated:** [May 29, 2021, 8:21am UTC](https://discourse.julialang.org/t/return-tuple-from-jump/62026 "2021-05-29T08:21:32Z")

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I have few questions on JuMP. Can we return JuMP results as a named tuple of termination status and variable values? See MWE below. Variables will not always contain values, eg. if model is infeasible, so I don’t know ho…

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## [Precompiling causing system freeze](https://discourse.julialang.org/t/precompiling-causing-system-freeze/62008)

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**Author:** [@evad](https://discourse.julialang.org/u/evad)\
**Replies:** 3\
**Last updated:** [May 29, 2021, 6:04am UTC](https://discourse.julialang.org/t/precompiling-causing-system-freeze/62008 "2021-05-29T06:04:27Z")

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Hi, I’m on a 10y-old machine, and each time I updated a few packages, a whopping 100+ packages got recompiled, and system hung if other resource intensive apps like YouTube page were running. I noticed compiling in R/Ha…

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## [What could cause some packages to be downgraded? (no obvious dependencies)](https://discourse.julialang.org/t/what-could-cause-some-packages-to-be-downgraded-no-obvious-dependencies/62021)

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**Author:** [@ptoche](https://discourse.julialang.org/u/ptoche)\
**Replies:** 1\
**Last updated:** [May 29, 2021, 5:30am UTC](https://discourse.julialang.org/t/what-could-cause-some-packages-to-be-downgraded-no-obvious-dependencies/62021 "2021-05-29T05:30:54Z")

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Is it ever possible that packages will be downgraded when Pkg.adding a package with no dependencies except Test? julia\> Pkg.add("some\_package") The Project.toml for the added package contains: \[deps\] \[compat\] juli…

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## [WebIO – simple examples?](https://discourse.julialang.org/t/webio-simple-examples/62028)

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**Author:** [@baptnz](https://discourse.julialang.org/u/baptnz)\
**Replies:** 0\
**Last updated:** [May 29, 2021, 1:07am UTC](https://discourse.julialang.org/t/webio-simple-examples/62028 "2021-05-29T01:07:37Z")

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I’m hoping to display a simple Three.js visual in the plot panel of Juno; unfortunately the working examples I’ve found are either too basic (displaying pure html tags), or too complicated (plotly, with full interactivit…

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## [Finding disk space on windows](https://discourse.julialang.org/t/finding-disk-space-on-windows/62004)

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**Author:** [@Jake](https://discourse.julialang.org/u/Jake)\
**Replies:** 2\
**Last updated:** [May 28, 2021, 10:35pm UTC](https://discourse.julialang.org/t/finding-disk-space-on-windows/62004 "2021-05-28T22:35:55Z")

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I am trying to obtain the total disk capacity and the amount of free disk space on a Windows 10 machine. I don’t see any Julia command that will do this so I thought that a Windows command would give me the required inf…

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## [What's the most efficient way to sum the results of multithreading?](https://discourse.julialang.org/t/whats-the-most-efficient-way-to-sum-the-results-of-multithreading/61944)

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**Author:** [@yingqiuz](https://discourse.julialang.org/u/yingqiuz)\
**Replies:** 3\
**Last updated:** [May 28, 2021, 10:23pm UTC](https://discourse.julialang.org/t/whats-the-most-efficient-way-to-sum-the-results-of-multithreading/61944 "2021-05-28T22:23:53Z")

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Hi, I need to sum the outputs of each thread. Is there a standard/efficient way to do this? for example: X = Matrix{Float64}(d, N) Threads.@threads for k = 1:N X\[:, k\] .= some\_calculations() end sum!(ones(Int64, d…

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## [Getting a 3D position from mouse click. Makie.jl](https://discourse.julialang.org/t/getting-a-3d-position-from-mouse-click-makie-jl/61880)

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**Author:** [@Aroeira](https://discourse.julialang.org/u/Aroeira)\
**Replies:** 4\
**Last updated:** [May 28, 2021, 9:56pm UTC](https://discourse.julialang.org/t/getting-a-3d-position-from-mouse-click-makie-jl/61880 "2021-05-28T21:56:50Z")

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Hello, I am using Makie.jl to plot molecular shapes. Right now I am using it mostly as a passive tool: read a file with xyz coordinates and plot them. I would like to add some more interaction to it. So my main question …

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## [Massive data-dependent floating-point slowdown](https://discourse.julialang.org/t/massive-data-dependent-floating-point-slowdown/62017)

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**Author:** [@stevengj](https://discourse.julialang.org/u/stevengj)\
**Replies:** 3\
**Last updated:** [May 28, 2021, 9:36pm UTC](https://discourse.julialang.org/t/massive-data-dependent-floating-point-slowdown/62017 "2021-05-28T21:36:17Z")

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I encountered a mysterious case where the same floating-point computation experiences a massive slowdown depending on the data — a factor of 20, or even 60 if I use @turbo from LoopVectorization.jl. I’m guessing it has …

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## [Why isn't string replace variadic?](https://discourse.julialang.org/t/why-isnt-string-replace-variadic/62020)

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**Author:** [@jzr](https://discourse.julialang.org/u/jzr)\
**Replies:** 1\
**Last updated:** [May 28, 2021, 9:09pm UTC](https://discourse.julialang.org/t/why-isnt-string-replace-variadic/62020 "2021-05-28T21:09:51Z")

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replace(s::AbstractString, pat=\>r; \[count::Integer\]) https://docs.julialang.org/en/v1/base/strings/#Base.replace-Tuple{AbstractString,%20Pair} If I want to make two replacements in one pass I have to use regex? It seem…

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## [Foolproof method for converting to Float64](https://discourse.julialang.org/t/foolproof-method-for-converting-to-float64/62011)

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**Author:** [@mjanun](https://discourse.julialang.org/u/mjanun)\
**Replies:** 10\
**Last updated:** [May 28, 2021, 8:56pm UTC](https://discourse.julialang.org/t/foolproof-method-for-converting-to-float64/62011 "2021-05-28T20:56:29Z")

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I am reading some data from a CSV file, which is intended to be Float64. But it does not always parses as Float64- some times its type is Any, some times String, some times integer, etc. To convert it to Float64, I use p…

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## [How to add dropdown menu inside Makie recipe?](https://discourse.julialang.org/t/how-to-add-dropdown-menu-inside-makie-recipe/62005)

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**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\
**Replies:** 5\
**Last updated:** [May 28, 2021, 8:23pm UTC](https://discourse.julialang.org/t/how-to-add-dropdown-menu-inside-makie-recipe/62005 "2021-05-28T20:23:17Z")

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Is there an example somewhere of a full recipe with interactive elements? I am searching through the master branch documentation but can’t find an example.

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## [Properly implement Base.hash() for custom type](https://discourse.julialang.org/t/properly-implement-base-hash-for-custom-type/61951)

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**Author:** [@anon60034542](https://discourse.julialang.org/u/anon60034542)\
**Replies:** 11\
**Last updated:** [May 28, 2021, 7:32pm UTC](https://discourse.julialang.org/t/properly-implement-base-hash-for-custom-type/61951 "2021-05-28T19:32:35Z")

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Consider the following code: @enum WeaponType CloseRange Reloadable struct GameWeapon damage::Int32 type::WeaponType end Reading the documentation, it says: New types should implement the 2-argument form, ty…

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