# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1929

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

**Page:** 1930

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## [Choosing only different vectors from a matrix](https://discourse.julialang.org/t/choosing-only-different-vectors-from-a-matrix/28237)

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**Author:** [@angeloaliano1](https://discourse.julialang.org/u/angeloaliano1)\
**Replies:** 8\
**Last updated:** [September 1, 2019, 7:51pm UTC](https://discourse.julialang.org/t/choosing-only-different-vectors-from-a-matrix/28237 "2019-09-01T19:51:15Z")

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Hello users, I have a matrix A: A=\[1.0 7.0 4.0 8.0 9.0 4.0 5.0 0.0 10.0 10.0 1.0 7.0 1.0 0.0 0.0 9.0 8.0 1.0 3.0 5.0 7.0 1.0 1.0 0.0 1.0 0.0 0.0 5.0 10.0 8.0 3.0 5.0 1.0 …

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## [Any tips on finding about memory leaks please?](https://discourse.julialang.org/t/any-tips-on-finding-about-memory-leaks-please/13019)

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**Author:** [@LeoK987](https://discourse.julialang.org/u/LeoK987)\
**Replies:** 19\
**Last updated:** [September 1, 2019, 6:08pm UTC](https://discourse.julialang.org/t/any-tips-on-finding-about-memory-leaks-please/13019 "2019-09-01T18:08:59Z")

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My code running in REPL causes memory usage (as shown in ‘top’) of julia to go up gradually. Calling gc() specifically doesn’y help much. Oftentimes, I have to restart julia. The code basically reads in a DataFrames v…

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## [Logout on Mac when using PyPlot (v1.2)](https://discourse.julialang.org/t/logout-on-mac-when-using-pyplot-v1-2/27842)

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**Author:** [@swishmas](https://discourse.julialang.org/u/swishmas)\
**Replies:** 9\
**Last updated:** [September 1, 2019, 6:01pm UTC](https://discourse.julialang.org/t/logout-on-mac-when-using-pyplot-v1-2/27842 "2019-09-01T18:01:28Z")

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Hi there, I just updated to v1.2 and run the code using PyPlot plot(\[i for i = 1:20\],\[i^2 for i = 1:20\]) And my Apple computer (Mojave, 2017) will log me out and close all my windows. Is there a crowd favorite plott…

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## [Count pairs in array whose sum is divisible by K](https://discourse.julialang.org/t/count-pairs-in-array-whose-sum-is-divisible-by-k/28266)

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**Author:** [@Fuad\_Sami](https://discourse.julialang.org/u/Fuad_Sami)\
**Replies:** 1\
**Last updated:** [September 1, 2019, 5:01pm UTC](https://discourse.julialang.org/t/count-pairs-in-array-whose-sum-is-divisible-by-k/28266 "2019-09-01T17:01:41Z")

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Given an array A\[\] and positive integer K , the task is to count total number of pairs in the array whose sum is divisible by K . Note : This question is generalised version of this Examples: Input : A = {2, 2, 1,…

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## [What is the purpose of having both "nodes" and "vertices" in the package OpenStreetMapX?](https://discourse.julialang.org/t/what-is-the-purpose-of-having-both-nodes-and-vertices-in-the-package-openstreetmapx/28265)

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**Author:** [@bsnyh](https://discourse.julialang.org/u/bsnyh)\
**Replies:** 0\
**Last updated:** [September 1, 2019, 3:51pm UTC](https://discourse.julialang.org/t/what-is-the-purpose-of-having-both-nodes-and-vertices-in-the-package-openstreetmapx/28265 "2019-09-01T15:51:39Z")

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Hi. I hope this is not a naive question. I’m working on the OpenStreetMapX package lately and I do not quite understand the purpose of having both “nodes” and “vertices” in the package. Is it necessary? Any comments are …

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## [Should I dispatch on singleton types or their instances?](https://discourse.julialang.org/t/should-i-dispatch-on-singleton-types-or-their-instances/28204)

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**Author:** [@singularitti](https://discourse.julialang.org/u/singularitti)\
**Replies:** 6\
**Last updated:** [September 1, 2019, 3:15pm UTC](https://discourse.julialang.org/t/should-i-dispatch-on-singleton-types-or-their-instances/28204 "2019-09-01T15:15:59Z")

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When I am developing packages, I often come across the following problem. struct Step{T} end func(::Step{1}, x) = do something... func(::Step{2}, x) = do some different things... I am not sure should I use singleton t…

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## [How to build CDDLib.jl on Windows ✅](https://discourse.julialang.org/t/how-to-build-cddlib-jl-on-windows/28114)

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**Author:** [@uwechsler](https://discourse.julialang.org/u/uwechsler)\
**Replies:** 1\
**Last updated:** [September 1, 2019, 2:48pm UTC](https://discourse.julialang.org/t/how-to-build-cddlib-jl-on-windows/28114 "2019-09-01T14:48:16Z")

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For my current project, I’d like to run CDDLib.jl on a Windows system. Currently, I get the following error message when trying to build the library. (v1.1) pkg\> build CDDLib Building SpecialFunctions → \`C:\\Users\\wue…

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## [Help porting Java code to Julia](https://discourse.julialang.org/t/help-porting-java-code-to-julia/28262)

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**Author:** [@Fuad\_Sami](https://discourse.julialang.org/u/Fuad_Sami)\
**Replies:** 10\
**Last updated:** [September 1, 2019, 2:12pm UTC](https://discourse.julialang.org/t/help-porting-java-code-to-julia/28262 "2019-09-01T14:12:44Z")

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\## where i wrote java, i need to convert it to julia. ##can some one tell me how ? thanks function MinimumUnique(arr::Vector{T}) where T\<:Integer map = Dict{T,Int}() sum = 0 for value in arr if !haskey…

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## [CRAM support?](https://discourse.julialang.org/t/cram-support/28222)

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**Author:** [@brendanofallon](https://discourse.julialang.org/u/brendanofallon)\
**Replies:** 5\
**Last updated:** [September 1, 2019, 2:10pm UTC](https://discourse.julialang.org/t/cram-support/28222 "2019-09-01T14:10:56Z")

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Hello, I’m wondering if there’s support, or plans for support, of the CRAM alignment format in BioJulia? I didn’t come across anything obvious reading the documentation, but perhaps it’s hiding somewhere, or a work in pr…

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## [How to profile / analyse / optimise large Julia apps](https://discourse.julialang.org/t/how-to-profile-analyse-optimise-large-julia-apps/28258)

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**Author:** [@essenciary](https://discourse.julialang.org/u/essenciary)\
**Replies:** 7\
**Last updated:** [September 1, 2019, 1:21pm UTC](https://discourse.julialang.org/t/how-to-profile-analyse-optimise-large-julia-apps/28258 "2019-09-01T13:21:26Z")

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What are the best practices for identifying performance bottlenecks in large Julia apps (with large function call stacks)? Genie apps are fairly complex, with a request → response cycle invoking easily over 100 Genie fun…

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## [Anyone using Julia for drones (or other embedded)? Any forseen problems?](https://discourse.julialang.org/t/anyone-using-julia-for-drones-or-other-embedded-any-forseen-problems/18755)

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**Author:** [@Palli](https://discourse.julialang.org/u/Palli)\
**Replies:** 18\
**Last updated:** [September 1, 2019, 9:47am UTC](https://discourse.julialang.org/t/anyone-using-julia-for-drones-or-other-embedded-any-forseen-problems/18755 "2019-09-01T09:47:13Z")

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\[I do know about the general garbage collection issue, that I’m not worried about; solved for robotics, see case studies at Julia Computing.\] Any hardware/OS combination a problem or has been proven to work, and I mostl…

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## [Any one can help me on this code](https://discourse.julialang.org/t/any-one-can-help-me-on-this-code/28251)

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**Author:** [@Fuad\_Sami](https://discourse.julialang.org/u/Fuad_Sami)\
**Replies:** 3\
**Last updated:** [September 1, 2019, 9:26am UTC](https://discourse.julialang.org/t/any-one-can-help-me-on-this-code/28251 "2019-09-01T09:26:59Z")

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\#this method sort the array that all #the even number in the first and the odd #number in the even, and reutnr #the number os swap, #e.g. in array = \[17,4,8\], there is a 17 odd number and 8 #even number. swaping so s…

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## [Most efficient way to compute number of rows in each group using JuliaDB?](https://discourse.julialang.org/t/most-efficient-way-to-compute-number-of-rows-in-each-group-using-juliadb/28256)

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**Author:** [@xiaodai](https://discourse.julialang.org/u/xiaodai)\
**Replies:** 0\
**Last updated:** [September 1, 2019, 8:01am UTC](https://discourse.julialang.org/t/most-efficient-way-to-compute-number-of-rows-in-each-group-using-juliadb/28256 "2019-09-01T08:01:37Z")

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Suppose a is a JuliaDB table, is the below the best (most efficient) way to compute the number of rows per group? using LambdaFn, DataFrames, JuliaDB a = DataFrame(Column1 = rand(\["a", "b", "c"\], 1\_000), b = rand(1000))…

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## [How do I fit a distribution to these data sets?!](https://discourse.julialang.org/t/how-do-i-fit-a-distribution-to-these-data-sets/28243)

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**Author:** [@mthelm85](https://discourse.julialang.org/u/mthelm85)\
**Replies:** 5\
**Last updated:** [September 1, 2019, 5:59am UTC](https://discourse.julialang.org/t/how-do-i-fit-a-distribution-to-these-data-sets/28243 "2019-09-01T05:59:22Z")

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Let me start by saying that I’m very inexperienced in this area, so go easy on me @Tamas\_Papp :wink:. I have two datasets that are similar in shape and I’m trying to fit a distribution to each of them with the goal of be…

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## [Trying to analyse Fannie Mae data with JuliaDB](https://discourse.julialang.org/t/trying-to-analyse-fannie-mae-data-with-juliadb/21410)

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**Author:** [@xiaodai](https://discourse.julialang.org/u/xiaodai)\
**Replies:** 14\
**Last updated:** [August 31, 2019, 11:27pm UTC](https://discourse.julialang.org/t/trying-to-analyse-fannie-mae-data-with-juliadb/21410 "2019-08-31T23:27:45Z")

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I am doing my best to analyse Fannie Mae data with JuliaDB. However the f First Step is to download the Fannie Mae Data and unzip them all Now I tried to load the data using loadtable but it didn’t work. So I split th…

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## [How does REPL helpmode work?](https://discourse.julialang.org/t/how-does-repl-helpmode-work/28244)

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**Author:** [@tgf314](https://discourse.julialang.org/u/tgf314)\
**Replies:** 2\
**Last updated:** [August 31, 2019, 11:26pm UTC](https://discourse.julialang.org/t/how-does-repl-helpmode-work/28244 "2019-08-31T23:26:30Z")

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If I type the following: using REPL REPL.\_helpmode( "push!" ) I get the following output: :(#= /home/flynn/projects/julia/julia-1.1/usr/share/julia/stdlib/v1.1/REPL/src/docview.jl:40 =# (REPL).@repl Base.TTY(RawFD(0x0…

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## [Custom iterator, simple example](https://discourse.julialang.org/t/custom-iterator-simple-example/28212)

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**Author:** [@Gus\_Hart](https://discourse.julialang.org/u/Gus_Hart)\
**Replies:** 6\
**Last updated:** [August 31, 2019, 10:24pm UTC](https://discourse.julialang.org/t/custom-iterator-simple-example/28212 "2019-08-31T22:24:30Z")

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I implemented Donald Knuth’s “Algorithm M” for generating all numbers in a mixed-radix numbering system. I would like to turn this into an iterator so I could loop over all of them but without having them all in memory a…

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## [Why this cannot compiling](https://discourse.julialang.org/t/why-this-cannot-compiling/28242)

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**Author:** [@Fuad\_Sami](https://discourse.julialang.org/u/Fuad_Sami)\
**Replies:** 11\
**Last updated:** [August 31, 2019, 6:15pm UTC](https://discourse.julialang.org/t/why-this-cannot-compiling/28242 "2019-08-31T18:15:53Z")

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function CountCell(commands::Vector{String}, n::Integer cell = 0 for i in 1:n if commands\[i\]==“up” && cell/n !=0 cell -=n end if commands\[i\]==“down” && cell/n !=n-1 cell +=n end if commands\[i\]==“right” && cell…

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## [\[ANN\] SurfaceTopology.jl, LaplaceBIE.jl and ElTopo.jl](https://discourse.julialang.org/t/ann-surfacetopology-jl-laplacebie-jl-and-eltopo-jl/28233)

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**Author:** [@Janis\_Erdmanis](https://discourse.julialang.org/u/Janis_Erdmanis)\
**Replies:** 1\
**Last updated:** [August 31, 2019, 5:53pm UTC](https://discourse.julialang.org/t/ann-surfacetopology-jl-laplacebie-jl-and-eltopo-jl/28233 "2019-08-31T17:53:34Z")

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During my last Master year, I worked on the simulation of a magnetic liquid droplet in a fast rotating field where experimentally star instability was observed. During this project, I had to find a way to calculate surfa…

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## [How do I convert an int to an array?](https://discourse.julialang.org/t/how-do-i-convert-an-int-to-an-array/28092)

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**Author:** [@abdul-naaser](https://discourse.julialang.org/u/abdul-naaser)\
**Replies:** 13\
**Last updated:** [August 31, 2019, 3:54pm UTC](https://discourse.julialang.org/t/how-do-i-convert-an-int-to-an-array/28092 "2019-08-31T15:54:28Z")

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Hello friendly Julia community, Suppose I have an integer. How do I convert this to an array? Specifically, I have a counter inside a local namespace of a function, call it, counts, and when I println it, I get: 1 2 4…

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## [How to activate a package in a script?](https://discourse.julialang.org/t/how-to-activate-a-package-in-a-script/28185)

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**Author:** [@joefowler](https://discourse.julialang.org/u/joefowler)\
**Replies:** 20\
**Last updated:** [August 31, 2019, 3:42pm UTC](https://discourse.julialang.org/t/how-to-activate-a-package-in-a-script/28185 "2019-08-31T15:42:08Z")

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I admit that the following problem might arise only because my team is mixing two concepts–Package and Application–in a single Project. Still, let me pose the problem: I have a package “Pope” that serves mainly as a lib…

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## [DrWatson 1.0 - the perfect sidekick to your scientific inquiries is out!](https://discourse.julialang.org/t/drwatson-1-0-the-perfect-sidekick-to-your-scientific-inquiries-is-out/28238)

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**Author:** [@Datseris](https://discourse.julialang.org/u/Datseris)\
**Replies:** 0\
**Last updated:** [August 31, 2019, 2:52pm UTC](https://discourse.julialang.org/t/drwatson-1-0-the-perfect-sidekick-to-your-scientific-inquiries-is-out/28238 "2019-08-31T14:52:22Z")

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Dear All, I am very happy to announce the first major release of DrWatson: version 1.0! Here is our documentation: DrWatson is a scientific project assistant software. It is a Julia package created to help people…

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## [What's actually inside precompiled Julia files?](https://discourse.julialang.org/t/whats-actually-inside-precompiled-julia-files/28234)

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**Author:** [@ninjaaron](https://discourse.julialang.org/u/ninjaaron)\
**Replies:** 2\
**Last updated:** [August 31, 2019, 2:19pm UTC](https://discourse.julialang.org/t/whats-actually-inside-precompiled-julia-files/28234 "2019-08-31T14:19:13Z")

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I’m talking about the files like those in the various subfolders of ~/.julia/compiled. Obviously machine code can’t really be compiled until all the all types are known–something that typically isn’t possible for entire…

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## [Some doubts about types](https://discourse.julialang.org/t/some-doubts-about-types/27635)

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**Author:** [@baptiste](https://discourse.julialang.org/u/baptiste)\
**Replies:** 8\
**Last updated:** [August 31, 2019, 2:00pm UTC](https://discourse.julialang.org/t/some-doubts-about-types/27635 "2019-08-31T14:00:00Z")

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I’ve ported a bit of code from R/Matlab/C++ to Julia a couple of times over the past few years and can get things to work, but I’m still not familiar with the best-practice, particularly around type declarations. My goal…

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## [Error in selecting column dataframe with Julia 1.2](https://discourse.julialang.org/t/error-in-selecting-column-dataframe-with-julia-1-2/28208)

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**Author:** [@Luigi\_Marongiu](https://discourse.julialang.org/u/Luigi_Marongiu)\
**Replies:** 3\
**Last updated:** [August 31, 2019, 1:26pm UTC](https://discourse.julialang.org/t/error-in-selecting-column-dataframe-with-julia-1-2/28208 "2019-08-31T13:26:42Z")

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Hello, I have been using this formula to get a value of a given dataframe’s column: julia\> println(df\[(df\[:Parameter\] .== "dilution"), :5\]\[1\] ) ┌ Warning: \`getindex(df::DataFrame, col\_ind::ColumnIndex)\` is depre…

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## [\[ANN\] Juno 0.9](https://discourse.julialang.org/t/ann-juno-0-9/27220)

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**Author:** [@aviatesk](https://discourse.julialang.org/u/aviatesk)\
**Replies:** 16\
**Last updated:** [August 31, 2019, 1:14pm UTC](https://discourse.julialang.org/t/ann-juno-0-9/27220 "2019-08-31T13:14:13Z")

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Hi all, Juno 0.9 is out and brings you lots of bugfixes, improvements, and some exiting new features. (Thanks for @pfitzseb for letting me take an release honour on behalf of him.) Release notes New features On hover…

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## [Logging to console and file](https://discourse.julialang.org/t/logging-to-console-and-file/28101)

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**Author:** [@essenciary](https://discourse.julialang.org/u/essenciary)\
**Replies:** 8\
**Last updated:** [August 31, 2019, 12:59pm UTC](https://discourse.julialang.org/t/logging-to-console-and-file/28101 "2019-08-31T12:59:55Z")

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I tried the example in the documentation a couple of times but I can’t get Julia to write to both console and file. The code in the documentation: # Load the logging module using Logging # Open a textfile for writing i…

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## [Replacing normal arrays with static arrays](https://discourse.julialang.org/t/replacing-normal-arrays-with-static-arrays/28230)

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**Author:** [@baptiste](https://discourse.julialang.org/u/baptiste)\
**Replies:** 6\
**Last updated:** [August 31, 2019, 12:21pm UTC](https://discourse.julialang.org/t/replacing-normal-arrays-with-static-arrays/28230 "2019-08-31T12:21:31Z")

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I’m trying to perform a 3D rotation on a diagonal matrix, which seems to work with the code below. using LinearAlgebra using StaticArrays function euler(φ, θ, ψ) R = Array{Float64}(undef,(3,3)) cosφ = cos(φ); …

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## [Comparison between time taken in Python and Julia](https://discourse.julialang.org/t/comparison-between-time-taken-in-python-and-julia/28159)

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**Author:** [@richie96](https://discourse.julialang.org/u/richie96)\
**Replies:** 2\
**Last updated:** [August 29, 2019, 11:39am UTC](https://discourse.julialang.org/t/comparison-between-time-taken-in-python-and-julia/28159 "2019-08-29T11:39:04Z")

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Hi, I am doing a comparison between Python and Julia by analyzing the same data set. I am using a data set containing nearly 800,000 rows of data. I load the data from two csv files containing equal amount of data each…

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## [Mixedmodels.jl branches: nlmm and dropmulαβ!](https://discourse.julialang.org/t/mixedmodels-jl-branches-nlmm-and-dropmul/28223)

<div class="topic-metadata">

**Author:** [@Juan](https://discourse.julialang.org/u/Juan)\
**Replies:** 2\
**Last updated:** [August 31, 2019, 11:48am UTC](https://discourse.julialang.org/t/mixedmodels-jl-branches-nlmm-and-dropmul/28223 "2019-08-31T11:48:43Z")

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I’ve seen the Mixedmodels.jl package has thre differente branches: master nlmm dropmulαβ! How are they different? What’s new there?

[Previous page](https://discourse.julialang.org/latest.md?page=1928)

[Next page](https://discourse.julialang.org/latest.md?page=1930)