# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1653

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

**Page:** 1654

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## [Flux training GPU vs CPU different results](https://discourse.julialang.org/t/flux-training-gpu-vs-cpu-different-results/45165)

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**Author:** [@luboshanus](https://discourse.julialang.org/u/luboshanus)\
**Replies:** 7\
**Last updated:** [August 20, 2020, 8:19pm UTC](https://discourse.julialang.org/t/flux-training-gpu-vs-cpu-different-results/45165 "2020-08-20T20:19:02Z")

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Hi, I have a problem while training on GPU vs CPU. Or when I just once run train function it goes completely off while on GPU. If I choose CPU it just stays “converge” and not go further away. An example of 3 runs on GP…

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## [Using Julia with Coral google board](https://discourse.julialang.org/t/using-julia-with-coral-google-board/33422)

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**Author:** [@Aizzaac](https://discourse.julialang.org/u/Aizzaac)\
**Replies:** 3\
**Last updated:** [August 20, 2020, 8:01pm UTC](https://discourse.julialang.org/t/using-julia-with-coral-google-board/33422 "2020-08-20T20:01:40Z")

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Hello I am doing a research where I have to do a benchmark between a PC with GPU vs the Coral board’s TPU. But I have to use Julia. The Coral board uses TensorFlow Lite. Any guidance will be appreciated.

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## [\[ANN\] ChemEquations.jl: write and balance chemical equations elegantly and efficiently](https://discourse.julialang.org/t/ann-chemequations-jl-write-and-balance-chemical-equations-elegantly-and-efficiently/44153)

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**Author:** [@anon37204545](https://discourse.julialang.org/u/anon37204545)\
**Replies:** 24\
**Last updated:** [August 20, 2020, 7:48pm UTC](https://discourse.julialang.org/t/ann-chemequations-jl-write-and-balance-chemical-equations-elegantly-and-efficiently/44153 "2020-08-20T19:48:05Z")

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Afte a few days of honest work and one Discourse thread, I’ve completed a package dedicated for chemical equations. Edit: It’s presented comprehensively on my blog. It is mostly based on the syntax of Balance Chemica…

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## [Unexpected behaviour for custom histogram limits in Gadfly](https://discourse.julialang.org/t/unexpected-behaviour-for-custom-histogram-limits-in-gadfly/45125)

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**Author:** [@IMoronPirate](https://discourse.julialang.org/u/IMoronPirate)\
**Replies:** 2\
**Last updated:** [August 20, 2020, 7:40pm UTC](https://discourse.julialang.org/t/unexpected-behaviour-for-custom-histogram-limits-in-gadfly/45125 "2020-08-20T19:40:49Z")

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If one plots the histogram of some data in Gadfly everything works fine. d = randn(250); plot(x=d, Geom.histogram(bincount=35)) However, providing the limits to plot the histogram of data between -5 and 0 plot(x=d,…

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## [Elimination of Errors in JuMP model](https://discourse.julialang.org/t/elimination-of-errors-in-jump-model/45266)

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**Author:** [@mamo](https://discourse.julialang.org/u/mamo)\
**Replies:** 4\
**Last updated:** [August 20, 2020, 7:06pm UTC](https://discourse.julialang.org/t/elimination-of-errors-in-jump-model/45266 "2020-08-20T19:06:45Z")

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Give me suggestions for eliminating these errors please: LoadError: MethodError: no method matching getindex(::Tuple{Pair{String,Tuple{String,String}},Pair{String,NTuple{11,String}},Pair{String,Tuple{String,String,Strin…

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## [If-else applied to a DataFrame](https://discourse.julialang.org/t/if-else-applied-to-a-dataframe/45238)

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**Author:** [@kabir\_sud](https://discourse.julialang.org/u/kabir_sud)\
**Replies:** 11\
**Last updated:** [August 20, 2020, 6:53pm UTC](https://discourse.julialang.org/t/if-else-applied-to-a-dataframe/45238 "2020-08-20T18:53:47Z")

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How can the IF ELSE loop be applied to a data frame. I want the loop to take the first 2 columns as conditions and give me an output in the final. For eg: if “col A” == 4 && “col B” == 2 print(“Yes”) else print(“no”…

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## [Julia 1.5.1 testing period](https://discourse.julialang.org/t/julia-1-5-1-testing-period/45280)

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**Author:** [@ararslan](https://discourse.julialang.org/u/ararslan)\
**Replies:** 0\
**Last updated:** [August 20, 2020, 5:51pm UTC](https://discourse.julialang.org/t/julia-1-5-1-testing-period/45280 "2020-08-20T17:51:31Z")

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The release-1.5 branch on the Julia repository now contains the set of commits we’re planning to tag as v1.5.1, the first patch release in the 1.5 series. The list of commits included since v1.5.0 is available here . As …

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## [Macro interpolation and MLJ.jl](https://discourse.julialang.org/t/macro-interpolation-and-mlj-jl/45273)

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**Author:** [@sdwfrost](https://discourse.julialang.org/u/sdwfrost)\
**Replies:** 1\
**Last updated:** [August 20, 2020, 5:14pm UTC](https://discourse.julialang.org/t/macro-interpolation-and-mlj-jl/45273 "2020-08-20T17:14:26Z")

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I’m trying to use the @load macro from MLJ.jl, which looks like this: classifier = @load AdaBoostClassifier I want to loop through multiple arguments, so I’d like to do something like cname = "AdaBoostClassifier" clas…

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## [Poisson processes for many related univariate time series](https://discourse.julialang.org/t/poisson-processes-for-many-related-univariate-time-series/45211)

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**Author:** [@mystis](https://discourse.julialang.org/u/mystis)\
**Replies:** 4\
**Last updated:** [August 20, 2020, 4:19pm UTC](https://discourse.julialang.org/t/poisson-processes-for-many-related-univariate-time-series/45211 "2020-08-20T16:19:21Z")

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Hi everyone, I’ve been wanting to do some time series forecasting with Turing, because I’d like forecasting intervals as well. For practice, I’d like to forecast the norway car sales dataset. In short, it has ten years …

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## [Processing Rows with multiple threads](https://discourse.julialang.org/t/processing-rows-with-multiple-threads/45253)

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**Author:** [@danielw2904](https://discourse.julialang.org/u/danielw2904)\
**Replies:** 6\
**Last updated:** [August 20, 2020, 2:36pm UTC](https://discourse.julialang.org/t/processing-rows-with-multiple-threads/45253 "2020-08-20T14:36:09Z")

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I find myself having to process a lot of data recently where a) the processing of two different rows is independent and b) processing each row is expensive. I find myself coding a version of the following every time: us…

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## [LightQuery 0.7.0](https://discourse.julialang.org/t/lightquery-0-7-0/45183)

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**Author:** [@bramtayl](https://discourse.julialang.org/u/bramtayl)\
**Replies:** 11\
**Last updated:** [August 20, 2020, 2:31pm UTC](https://discourse.julialang.org/t/lightquery-0-7-0/45183 "2020-08-20T14:31:16Z")

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LighQuery 0.7 is out. It uses Base named tuples and as such is much much easier to use. I’m hoping that to have reached some level of interface stability, and that future changes will focus on performance. You should alr…

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## [Best Practices for Parallel implementation of Gibbs Sampler algorithm on single machine](https://discourse.julialang.org/t/best-practices-for-parallel-implementation-of-gibbs-sampler-algorithm-on-single-machine/45270)

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**Author:** [@deburgess](https://discourse.julialang.org/u/deburgess)\
**Replies:** 0\
**Last updated:** [August 20, 2020, 1:52pm UTC](https://discourse.julialang.org/t/best-practices-for-parallel-implementation-of-gibbs-sampler-algorithm-on-single-machine/45270 "2020-08-20T13:52:49Z")

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I am re-posting in this section as it seems a more relevant forum thant “Julia at Scale”. Thanks in advance for your comments and advice. Would someone comment on how to improve my coding? In particular: did I use @s…

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## [Orthotope grid type (generalization of AbstractRange)](https://discourse.julialang.org/t/orthotope-grid-type-generalization-of-abstractrange/45072)

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**Author:** [@chakravala](https://discourse.julialang.org/u/chakravala)\
**Replies:** 8\
**Last updated:** [August 20, 2020, 1:47pm UTC](https://discourse.julialang.org/t/orthotope-grid-type-generalization-of-abstractrange/45072 "2020-08-20T13:47:36Z")

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So, I’ve found that in several separate packages I need something like an Orthotope type struct Orthotope{N,T} min::SVector{N,T} max::SVector{N,T} end Or in other words, a hyper-rectangle, specified by minimum …

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## [A histogram that averages metadata instead of counts](https://discourse.julialang.org/t/a-histogram-that-averages-metadata-instead-of-counts/45257)

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**Author:** [@yakir12](https://discourse.julialang.org/u/yakir12)\
**Replies:** 6\
**Last updated:** [August 20, 2020, 12:59pm UTC](https://discourse.julialang.org/t/a-histogram-that-averages-metadata-instead-of-counts/45257 "2020-08-20T12:59:42Z")

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I have a bunch of coordinates and corresponding values: n = 100 xy = \[rand(2) for \_ in 1:n\] v = rand(n) I want to 2D-bin the coordinates, and calculate the mean of all the values, v, that fall into each corresponding b…

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## [\`unsafe\_pointer\_to\_objref(::Ptr{T})\` is not type stable](https://discourse.julialang.org/t/unsafe-pointer-to-objref-ptr-t-is-not-type-stable/45256)

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**Author:** [@mgkuhn](https://discourse.julialang.org/u/mgkuhn)\
**Replies:** 1\
**Last updated:** [August 20, 2020, 12:33pm UTC](https://discourse.julialang.org/t/unsafe-pointer-to-objref-ptr-t-is-not-type-stable/45256 "2020-08-20T12:33:57Z")

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Example code: mutable struct Foo{T} v::Vector{T} n::Int # possibly lots more fields, which I don't want # to have to copy each time with unsafe\_{load,store!} end function demo() a = Foo{Int64}(\[1\], …

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## [Help needed fixing stack overflow](https://discourse.julialang.org/t/help-needed-fixing-stack-overflow/45134)

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**Author:** [@Allan\_Baker](https://discourse.julialang.org/u/Allan_Baker)\
**Replies:** 14\
**Last updated:** [August 20, 2020, 12:21pm UTC](https://discourse.julialang.org/t/help-needed-fixing-stack-overflow/45134 "2020-08-20T12:21:17Z")

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I have a composite type that I use to simplify xy and xyz vector operations. I use it instead of an array or a static array because it doesn’t rely on external packages and is fairly quick and allows me to easily overlo…

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## [Solving Boundary Value Problems with Shooting() and DifferentialEquations.jl](https://discourse.julialang.org/t/solving-boundary-value-problems-with-shooting-and-differentialequations-jl/45265)

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**Author:** [@Gregers](https://discourse.julialang.org/u/Gregers)\
**Replies:** 0\
**Last updated:** [August 20, 2020, 11:37am UTC](https://discourse.julialang.org/t/solving-boundary-value-problems-with-shooting-and-differentialequations-jl/45265 "2020-08-20T11:37:20Z")

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Hey, Im trying to solve a Boundary Value Problems with Shooting() and DifferentialEquations.jl. My problem is formulated as this: This problem is an IVP with known initial values and has also a known analytical solu…

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## [Distributed loading packages](https://discourse.julialang.org/t/distributed-loading-packages/45224)

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**Author:** [@Joao\_Barata](https://discourse.julialang.org/u/Joao_Barata)\
**Replies:** 2\
**Last updated:** [August 20, 2020, 10:42am UTC](https://discourse.julialang.org/t/distributed-loading-packages/45224 "2020-08-20T10:42:57Z")

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Hi, I’m trying to use distributed computing, but am running into some trouble with loading packages. Here is the MWE: module bogus\_module using Parameters, Distributed @with\_kw mutable struct cenas # …

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## [Using Gradient Function from ForwardDiff with Structures](https://discourse.julialang.org/t/using-gradient-function-from-forwarddiff-with-structures/45188)

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**Author:** [@smickus](https://discourse.julialang.org/u/smickus)\
**Replies:** 3\
**Last updated:** [August 20, 2020, 9:39am UTC](https://discourse.julialang.org/t/using-gradient-function-from-forwarddiff-with-structures/45188 "2020-08-20T09:39:01Z")

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I am trying to use the gradient function from the ForwardDiff package with a function that has an input that is a structure. The issue that I am having is that I am unable to figure out how to have my function handle th…

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## [Help with parallel loop for eigenvalue calculations](https://discourse.julialang.org/t/help-with-parallel-loop-for-eigenvalue-calculations/45153)

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**Author:** [@Albert\_de\_montserrat](https://discourse.julialang.org/u/Albert_de_montserrat)\
**Replies:** 1\
**Last updated:** [August 20, 2020, 8:31am UTC](https://discourse.julialang.org/t/help-with-parallel-loop-for-eigenvalue-calculations/45153 "2020-08-20T08:31:16Z")

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In my Stokes solver I need to compute the eigenvalues and eigenvectors of several thousands of small 2x2 matrices. The ij components of this matrices are stored in n-by-6 matrices (F\_ij). I’d like to parallelise this co…

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## [All the ways to group-reduce sorted vectors. Ideas?](https://discourse.julialang.org/t/all-the-ways-to-group-reduce-sorted-vectors-ideas/45239)

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**Author:** [@xiaodai](https://discourse.julialang.org/u/xiaodai)\
**Replies:** 6\
**Last updated:** [August 20, 2020, 7:59am UTC](https://discourse.julialang.org/t/all-the-ways-to-group-reduce-sorted-vectors-ideas/45239 "2020-08-20T07:59:08Z")

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I have two vectors of the same length feature and target and I wish to do a group-reduce. We also have that feature is SORTED and possibly contain missing. I wish to do a group by on feature and sum(target). In SQL for…

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## [File path "/" vs "\\" (fslash vs backslash)](https://discourse.julialang.org/t/file-path-vs-fslash-vs-backslash/45244)

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**Author:** [@TheLateKronos](https://discourse.julialang.org/u/TheLateKronos)\
**Replies:** 2\
**Last updated:** [August 20, 2020, 7:04am UTC](https://discourse.julialang.org/t/file-path-vs-fslash-vs-backslash/45244 "2020-08-20T07:04:39Z")

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When I copy a file-path from the windows file explorer, the format is like this: C:\\Users\\MyUser\\Folder\\File.jl When I want to read this file in Julia, when trying to read a CSV or include() custom functions, I try to u…

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## [Series of Online Research Software Events SORSE 2nd September](https://discourse.julialang.org/t/series-of-online-research-software-events-sorse-2nd-september/45245)

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**Author:** [@johnh](https://discourse.julialang.org/u/johnh)\
**Replies:** 1\
**Last updated:** [August 20, 2020, 6:51am UTC](https://discourse.julialang.org/t/series-of-online-research-software-events-sorse-2nd-september/45245 "2020-08-20T06:51:44Z")

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You are invited to join us at the launch event of SORSE (a Series of Online Research Software Events) on Wednesday 2nd September 2020, 13:00 UTC . Registration can be found here . With the cancellation of many resea…

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## [\[ANN\] ExtremalOptimization.jl: gradient-free optimizer over continuous spaces](https://discourse.julialang.org/t/ann-extremaloptimization-jl-gradient-free-optimizer-over-continuous-spaces/45085)

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**Author:** [@francesco.alemanno](https://discourse.julialang.org/u/francesco.alemanno)\
**Replies:** 1\
**Last updated:** [August 19, 2020, 5:33pm UTC](https://discourse.julialang.org/t/ann-extremaloptimization-jl-gradient-free-optimizer-over-continuous-spaces/45085 "2020-08-19T17:33:17Z")

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Hi everyone, i made a super tiny package which could be useful to people attempting to optimize functions which have many multiple local minima and/or jumps, this algorithm finds solutions via a non-greedy policy, it do…

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## [Measuring and storing execution time in a variable](https://discourse.julialang.org/t/measuring-and-storing-execution-time-in-a-variable/45236)

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**Author:** [@trathi](https://discourse.julialang.org/u/trathi)\
**Replies:** 2\
**Last updated:** [August 20, 2020, 4:50am UTC](https://discourse.julialang.org/t/measuring-and-storing-execution-time-in-a-variable/45236 "2020-08-20T04:50:03Z")

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I want to measure the time from the moment the code enters pmap and exit it. Also, I want to store it in a variable. So is there a way I can store the output of @time or is there a julia package that does it more efficie…

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## [Modify the output of one jupyter cell from another?](https://discourse.julialang.org/t/modify-the-output-of-one-jupyter-cell-from-another/45235)

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**Author:** [@danspielman](https://discourse.julialang.org/u/danspielman)\
**Replies:** 0\
**Last updated:** [August 20, 2020, 2:07am UTC](https://discourse.julialang.org/t/modify-the-output-of-one-jupyter-cell-from-another/45235 "2020-08-20T02:07:22Z")

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Does anyone know if it is possible to modify the text portion of the output of a Jupyter cell from another cell? I don’t need to modify the values of variables. Just the text that appears. The following link shows how …

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## [Modifying arrays by views on workers](https://discourse.julialang.org/t/modifying-arrays-by-views-on-workers/45198)

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**Author:** [@tansongchen](https://discourse.julialang.org/u/tansongchen)\
**Replies:** 4\
**Last updated:** [August 20, 2020, 1:54am UTC](https://discourse.julialang.org/t/modifying-arrays-by-views-on-workers/45198 "2020-08-20T01:54:17Z")

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Julia has been good in my parallel computing works, however I encounter an issue recently. Let’s say I have an array a and I would like a @view as a shortcut to modify or refer to part of a, so I make a data structure ab…

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## [Is Julia able to replace C?](https://discourse.julialang.org/t/is-julia-able-to-replace-c/45178)

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**Author:** [@Steve.jl](https://discourse.julialang.org/u/Steve.jl)\
**Replies:** 8\
**Last updated:** [August 19, 2020, 11:08pm UTC](https://discourse.julialang.org/t/is-julia-able-to-replace-c/45178 "2020-08-19T23:08:54Z")

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AFAIK some things are written in C to build up the foundation for Julia. Could this stuff be replaced such that everything is written in Julia and a whole OS could be written in Julia? And if so, what’s the reason for st…

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## [Make entire function constant fold](https://discourse.julialang.org/t/make-entire-function-constant-fold/45229)

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**Author:** [@Oscar\_Smith](https://discourse.julialang.org/u/Oscar_Smith)\
**Replies:** 4\
**Last updated:** [August 19, 2020, 10:03pm UTC](https://discourse.julialang.org/t/make-entire-function-constant-fold/45229 "2020-08-19T22:03:27Z")

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Right now, in BetterExp, I have code that looks like MAX\_EXP(::Val{2}, ::Type{Float64}) = 1024.0 # log2 2^1023\*(2-2^-52) MIN\_EXP(::Val{2}, ::Type{Float64}) = -1075.0 # log2 2^-1075…

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## [Calling Reader from Various Directories](https://discourse.julialang.org/t/calling-reader-from-various-directories/45196)

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**Author:** [@Holdmycoffee](https://discourse.julialang.org/u/Holdmycoffee)\
**Replies:** 3\
**Last updated:** [August 19, 2020, 9:06pm UTC](https://discourse.julialang.org/t/calling-reader-from-various-directories/45196 "2020-08-19T21:06:01Z")

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Hi all, I have a function living in a local module, which reads some locally saved files in my package using an path: “src/folder1/…/myfile.txt”. Its purpose is solely to read and return the contents of the file. The pr…

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