# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1587

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

**Page:** 1588

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## [JuMP & NLopt: Optimizer not defined](https://discourse.julialang.org/t/jump-nlopt-optimizer-not-defined/49331)

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**Author:** [@Obtuya7](https://discourse.julialang.org/u/Obtuya7)\
**Replies:** 5\
**Last updated:** [October 30, 2020, 10:34pm UTC](https://discourse.julialang.org/t/jump-nlopt-optimizer-not-defined/49331 "2020-10-30T22:34:16Z")

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I’m trying to run the JuMP example code from the NLopt.jl page. I found someone who had a similar issue which was fixed through a restart. Unfortunately, it didn’t work in my case. Julia, JuMP, and NLopt are up to date a…

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## [Retrieve kwarg declaration type](https://discourse.julialang.org/t/retrieve-kwarg-declaration-type/49324)

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**Author:** [@Benjia](https://discourse.julialang.org/u/Benjia)\
**Replies:** 5\
**Last updated:** [October 30, 2020, 8:19pm UTC](https://discourse.julialang.org/t/retrieve-kwarg-declaration-type/49324 "2020-10-30T20:19:47Z")

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If I define a method: f(x; y::Int) = x \* y How can I retrieve the ::Int annotation on y, via reflection? I’ve poked around some of the method table properties, but can’t see it anywhere. It’s definitely stored somewher…

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## [Multivariate (multiple response) regression using matrixnormal in Turing](https://discourse.julialang.org/t/multivariate-multiple-response-regression-using-matrixnormal-in-turing/49323)

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**Author:** [@Kokora](https://discourse.julialang.org/u/Kokora)\
**Replies:** 0\
**Last updated:** [October 30, 2020, 7:23pm UTC](https://discourse.julialang.org/t/multivariate-multiple-response-regression-using-matrixnormal-in-turing/49323 "2020-10-30T19:23:41Z")

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Hi all, I am new to Turing and wanted to play on a toy example with a multiple response regression. Here is the code. Any help will be greatly appreciated. #— Code started here using Distributions, LinearAlgebra using…

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## [From Int64 to Int128](https://discourse.julialang.org/t/from-int64-to-int128/49322)

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**Author:** [@RWS](https://discourse.julialang.org/u/RWS)\
**Replies:** 5\
**Last updated:** [October 30, 2020, 7:12pm UTC](https://discourse.julialang.org/t/from-int64-to-int128/49322 "2020-10-30T19:12:33Z")

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Hi there, I (as a noob) have a basic question: x = typemax(Int32) x = x + 1 typeof(x) i get Int64. So we go from Int32 to Int64 y = typemax(Int64) y = y + 1 y now is -9223372036854775808 Why we cannot go to Int128…

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## [What is Base.KeySet()?](https://discourse.julialang.org/t/what-is-base-keyset/49314)

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**Author:** [@anon60034542](https://discourse.julialang.org/u/anon60034542)\
**Replies:** 3\
**Last updated:** [October 30, 2020, 7:01pm UTC](https://discourse.julialang.org/t/what-is-base-keyset/49314 "2020-10-30T19:01:14Z")

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When I use keys() the resulting data structure is a Base.KeySet(). Can someone elaborate on what that is? I searched the documentation, but I couldn’t find it. character\_inventory = Dict{String,Int32}("Sword" =\> 100, "S…

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## [Fast sympy vectorization on julia Arrays](https://discourse.julialang.org/t/fast-sympy-vectorization-on-julia-arrays/49318)

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**Author:** [@CorbinFoucart](https://discourse.julialang.org/u/CorbinFoucart)\
**Replies:** 1\
**Last updated:** [October 30, 2020, 6:52pm UTC](https://discourse.julialang.org/t/fast-sympy-vectorization-on-julia-arrays/49318 "2020-10-30T18:52:10Z")

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I have a python library I’ve built on sympy and specifically sympy.vector which does vector calculus computations (divergence, gradient, curl, laplacians, etc) for calculations related to PDEs. Sympy provides methods tha…

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## [Roborace - crashes due to NaN](https://discourse.julialang.org/t/roborace-crashes-due-to-nan/49310)

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**Author:** [@johnh](https://discourse.julialang.org/u/johnh)\
**Replies:** 1\
**Last updated:** [October 30, 2020, 2:41pm UTC](https://discourse.julialang.org/t/roborace-crashes-due-to-nan/49310 "2020-10-30T14:41:23Z")

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utonomous racer - crashes (literally) due to NaN

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## [Error with multiprocessing in VSCode Julia](https://discourse.julialang.org/t/error-with-multiprocessing-in-vscode-julia/46450)

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**Author:** [@bender9000](https://discourse.julialang.org/u/bender9000)\
**Replies:** 1\
**Last updated:** [October 30, 2020, 2:14pm UTC](https://discourse.julialang.org/t/error-with-multiprocessing-in-vscode-julia/46450 "2020-10-30T14:14:45Z")

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I am trying to start Julia interpreter in VSCode with additional arguments -p 4 and getting this error. ERROR: LoadError: On worker 2: ArgumentError: Package VSCodeServer \[9f5989ce-84fe-42d4-91ec-6a7a8d53ed0f\] is requir…

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## [Help with Registry.toml missing](https://discourse.julialang.org/t/help-with-registry-toml-missing/49304)

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**Author:** [@Stephen\_Wild](https://discourse.julialang.org/u/Stephen_Wild)\
**Replies:** 2\
**Last updated:** [October 30, 2020, 1:36pm UTC](https://discourse.julialang.org/t/help-with-registry-toml-missing/49304 "2020-10-30T13:36:59Z")

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Hi everyone, I am starting to learn julia. I am trying to install some new packages, but I receive the following message when I try to install packages: (@v1.5) pkg\> add LinearAlgebra Installing known registries int…

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## [How to run a Julia file with PyJulia](https://discourse.julialang.org/t/how-to-run-a-julia-file-with-pyjulia/49282)

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**Author:** [@Rita\_Paz](https://discourse.julialang.org/u/Rita_Paz)\
**Replies:** 4\
**Last updated:** [October 30, 2020, 1:19pm UTC](https://discourse.julialang.org/t/how-to-run-a-julia-file-with-pyjulia/49282 "2020-10-30T13:19:47Z")

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I have a Julia file called ‘func1.jl’ with two defined functions that uses the ‘LowRankApprox’ package. Julia, it is working well. But I need it to work in Python. When I import to Python, with PyJulia, it doesn’t work. …

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## [World age problem, when does a generated function get generated?](https://discourse.julialang.org/t/world-age-problem-when-does-a-generated-function-get-generated/49302)

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**Author:** [@louisponet](https://discourse.julialang.org/u/louisponet)\
**Replies:** 0\
**Last updated:** [October 30, 2020, 1:02pm UTC](https://discourse.julialang.org/t/world-age-problem-when-does-a-generated-function-get-generated/49302 "2020-10-30T13:02:11Z")

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I’m having a very confusing interaction between GLAbstraction.jl and ColorTypes.jl. I’ve read through pretty much all the world age threads and info I could find but I still don’t understand what is going wrong. The str…

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## [@cuStaticSharedMem multidimensional indexing seems not to work](https://discourse.julialang.org/t/custaticsharedmem-multidimensional-indexing-seems-not-to-work/49262)

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**Author:** [@R366Y](https://discourse.julialang.org/u/R366Y)\
**Replies:** 2\
**Last updated:** [October 30, 2020, 12:47pm UTC](https://discourse.julialang.org/t/custaticsharedmem-multidimensional-indexing-seems-not-to-work/49262 "2020-10-30T12:47:02Z")

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Hi, I’m trying to run a simple kernel with shared static memory having dimension 2. The trouble starts when I try to assing a value to the shared static memory, the kernel fail to compile. module GPU\_SHARED\_BITMAP fun…

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## [CSV 0.7.7 Error](https://discourse.julialang.org/t/csv-0-7-7-error/49256)

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**Author:** [@orthoeng](https://discourse.julialang.org/u/orthoeng)\
**Replies:** 8\
**Last updated:** [October 30, 2020, 12:38pm UTC](https://discourse.julialang.org/t/csv-0-7-7-error/49256 "2020-10-30T12:38:14Z")

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Hello All, Julia is new to me and I have been having a problem I’m hope I can get some help. I was having a CSV.write problem that I posted on Stackoverflow (Bogumił Kamiński) was kind enough to help me. He suggested I…

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## [Packages for instrumenting / rewriting Julia code (at Expr level)?](https://discourse.julialang.org/t/packages-for-instrumenting-rewriting-julia-code-at-expr-level/37742)

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**Author:** [@robertfeldt](https://discourse.julialang.org/u/robertfeldt)\
**Replies:** 3\
**Last updated:** [October 30, 2020, 10:29am UTC](https://discourse.julialang.org/t/packages-for-instrumenting-rewriting-julia-code-at-expr-level/37742 "2020-10-30T10:29:40Z")

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I know of Cassette.jl but my impression is that it requires knowledge about lower-level Julia compilation/execution stages. Are there other good options/packages/approaches for instrumenting Julia code at the Expr level? …

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## [Use stable version of package while developing](https://discourse.julialang.org/t/use-stable-version-of-package-while-developing/49261)

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**Author:** [@lmiq](https://discourse.julialang.org/u/lmiq)\
**Replies:** 7\
**Last updated:** [October 30, 2020, 10:05am UTC](https://discourse.julialang.org/t/use-stable-version-of-package-while-developing/49261 "2020-10-30T10:05:15Z")

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I am developing a package, changing the files in .julia/dev/Package. Usually, my development workflow is: using Revise \] dev Package using Package However, from time to time I want to use the stable version of the same…

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## [Append an array inside a function](https://discourse.julialang.org/t/append-an-array-inside-a-function/49289)

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**Author:** [@Nova](https://discourse.julialang.org/u/Nova)\
**Replies:** 6\
**Last updated:** [October 30, 2020, 8:49am UTC](https://discourse.julialang.org/t/append-an-array-inside-a-function/49289 "2020-10-30T08:49:23Z")

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I don’t really understand the scope of the variable SV here. I used it inside a function, so I expect that when I add elements to it, it should work fine: SV = rand(10, 1) function add\_star(SV) for i =1:5 …

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## [Using SymEngine. Functions not defined](https://discourse.julialang.org/t/using-symengine-functions-not-defined/49270)

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**Author:** [@brett\_knoss](https://discourse.julialang.org/u/brett_knoss)\
**Replies:** 4\
**Last updated:** [October 30, 2020, 7:18am UTC](https://discourse.julialang.org/t/using-symengine-functions-not-defined/49270 "2020-10-30T07:18:28Z")

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using SymEngine julia\> expand(a + 2(b+2)^2 + 2a + 3(a+1)) when I try to do this, I get error, expand not defined. I think that means it’s not fiding SymEngine.

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## [SciMl/Differential equations for modeling clinic medicine](https://discourse.julialang.org/t/sciml-differential-equations-for-modeling-clinic-medicine/48982)

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**Author:** [@timothyhartzog](https://discourse.julialang.org/u/timothyhartzog)\
**Replies:** 8\
**Last updated:** [October 30, 2020, 5:30am UTC](https://discourse.julialang.org/t/sciml-differential-equations-for-modeling-clinic-medicine/48982 "2020-10-30T05:30:42Z")

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After watching numerous lectures by Dr. Christopher Rackauckas, i am trying to develop the theory/understanding of using SciMl/differential equations vs biostats in modeling clinical medicinal problems? Biostats/eviden…

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## [Calling Windows API from Julia](https://discourse.julialang.org/t/calling-windows-api-from-julia/25123)

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**Author:** [@gabrielfreire](https://discourse.julialang.org/u/gabrielfreire)\
**Replies:** 19\
**Last updated:** [October 30, 2020, 3:54am UTC](https://discourse.julialang.org/t/calling-windows-api-from-julia/25123 "2020-10-30T03:54:12Z")

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Hi Julians, I am trying to implement a script that will list all Fonts installed on Windows using Gdi32.dll. First of all, here is the full script so you can make sense of what i’m about to write below: https://github.…

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## [Defining custom brackets for custom objects](https://discourse.julialang.org/t/defining-custom-brackets-for-custom-objects/49273)

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**Author:** [@giancarloantonucci](https://discourse.julialang.org/u/giancarloantonucci)\
**Replies:** 8\
**Last updated:** [October 30, 2020, 1:18am UTC](https://discourse.julialang.org/t/defining-custom-brackets-for-custom-objects/49273 "2020-10-30T01:18:26Z")

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Is it possible to define a method/function/macro/etc so that I can use ⟦⟧ to index a custom vector/struct? I’m looking for some kind of trick that would allow me to do something like the following: struct MyVec data…

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## [Auto adjust fontsize in Plots.jl](https://discourse.julialang.org/t/auto-adjust-fontsize-in-plots-jl/49276)

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**Author:** [@libensvivit](https://discourse.julialang.org/u/libensvivit)\
**Replies:** 0\
**Last updated:** [October 30, 2020, 12:50am UTC](https://discourse.julialang.org/t/auto-adjust-fontsize-in-plots-jl/49276 "2020-10-30T00:50:25Z")

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In Plots, I’m using custom ticks and save the plot in high resolution with size attribute. However, as far as I have seen Plots does not adjust the font size of anything when this attribute is used, and the user has to a…

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## [Simple benchmarks to run to test WSL2 vs Windows Native](https://discourse.julialang.org/t/simple-benchmarks-to-run-to-test-wsl2-vs-windows-native/40343)

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**Author:** [@affans](https://discourse.julialang.org/u/affans)\
**Replies:** 8\
**Last updated:** [October 30, 2020, 12:43am UTC](https://discourse.julialang.org/t/simple-benchmarks-to-run-to-test-wsl2-vs-windows-native/40343 "2020-10-30T00:43:01Z")

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I just upgraded to the new Windows May update which now has WSL 2 (a very lightweight, Hyper V VM running full Linux). I essentially now want to move all my development over to Linux. But I would like to test if there ar…

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## [Adding a complex value to an element of a real array results in InexactError](https://discourse.julialang.org/t/adding-a-complex-value-to-an-element-of-a-real-array-results-in-inexacterror/49271)

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**Author:** [@useless-machine](https://discourse.julialang.org/u/useless-machine)\
**Replies:** 3\
**Last updated:** [October 29, 2020, 11:33pm UTC](https://discourse.julialang.org/t/adding-a-complex-value-to-an-element-of-a-real-array-results-in-inexacterror/49271 "2020-10-29T23:33:56Z")

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Hi, I’m just getting started with Julia and I’ve read that Julia does automatic conversion and promotion of variables, thus U = 0 U = U + 1im works properly. However, the following code U = zeros(4) U\[2\] = 1im give…

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## [Thoughts on the Taichi programming language - sparse computing and differentiable programming](https://discourse.julialang.org/t/thoughts-on-the-taichi-programming-language-sparse-computing-and-differentiable-programming/49251)

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**Author:** [@mohamed82008](https://discourse.julialang.org/u/mohamed82008)\
**Replies:** 5\
**Last updated:** [October 29, 2020, 9:56pm UTC](https://discourse.julialang.org/t/thoughts-on-the-taichi-programming-language-sparse-computing-and-differentiable-programming/49251 "2020-10-29T21:56:51Z")

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I recently came across the Taichi programming language and I was curious what people here think about it and how it compares to Julia and Swift. It seems to have a special focus on “spatially sparse computing” and differ…

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## [Very slow execution time in comparison even to Python](https://discourse.julialang.org/t/very-slow-execution-time-in-comparison-even-to-python/49223)

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**Author:** [@Yury\_Kotlyarov](https://discourse.julialang.org/u/Yury_Kotlyarov)\
**Replies:** 35\
**Last updated:** [October 29, 2020, 9:38pm UTC](https://discourse.julialang.org/t/very-slow-execution-time-in-comparison-even-to-python/49223 "2020-10-29T21:38:53Z")

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I am new to Julia. While choosing a programming language for our next project wrote a short program in Julia: using LinearAlgebra using Statistics using Random import Base: +, - struct Point x::Float64 y::Flo…

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## [How to deploy a machine learning model as a REST endpoint](https://discourse.julialang.org/t/how-to-deploy-a-machine-learning-model-as-a-rest-endpoint/18638)

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**Author:** [@rwatts3](https://discourse.julialang.org/u/rwatts3)\
**Replies:** 4\
**Last updated:** [October 29, 2020, 8:51pm UTC](https://discourse.julialang.org/t/how-to-deploy-a-machine-learning-model-as-a-rest-endpoint/18638 "2020-10-29T20:51:16Z")

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Greetings, I will be developing a series of machine learning models that I would like to then deploy via a REST endpoint for a service. I am fairly new to the Julia community so I currently don’t have knowledge of the…

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## [Defining Unitful Units Programmatically](https://discourse.julialang.org/t/defining-unitful-units-programmatically/49260)

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**Author:** [@DrPapa](https://discourse.julialang.org/u/DrPapa)\
**Replies:** 0\
**Last updated:** [October 29, 2020, 8:07pm UTC](https://discourse.julialang.org/t/defining-unitful-units-programmatically/49260 "2020-10-29T20:07:40Z")

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I am processing some datasets involving altitude measurements that mixes MSL and AGL altitude units. I would like to define custom units to minimize opportunity for error. In my case, the reference offset altitude will b…

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## [PyCall installation problem?](https://discourse.julialang.org/t/pycall-installation-problem/7269)

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**Author:** [@BLI](https://discourse.julialang.org/u/BLI)\
**Replies:** 10\
**Last updated:** [October 29, 2020, 7:25pm UTC](https://discourse.julialang.org/t/pycall-installation-problem/7269 "2020-10-29T19:25:18Z")

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Hi, I’m trying to update PyPlot and IJulia, but the update/addition stalls – it seems like the problem is PyCall: julia\> Pkg.add(“PyCall”) INFO: Installing PyCall v1.15.0 INFO: Building Conda INFO: Building PyCall I…

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## [JuMP abs in expression macro](https://discourse.julialang.org/t/jump-abs-in-expression-macro/49196)

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**Author:** [@Paul\_McVay](https://discourse.julialang.org/u/Paul_McVay)\
**Replies:** 3\
**Last updated:** [October 29, 2020, 6:08pm UTC](https://discourse.julialang.org/t/jump-abs-in-expression-macro/49196 "2020-10-29T18:08:48Z")

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I am hoping to extend the expression/objective JuMP macro to automatically introduce the necessary slack variable when using absolute values. I don’t have a lot of experience with JuMP internals and was hoping for some p…

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## [Avoid getting a ReshapedArray when calling reshape?](https://discourse.julialang.org/t/avoid-getting-a-reshapedarray-when-calling-reshape/49255)

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**Author:** [@DrChainsaw](https://discourse.julialang.org/u/DrChainsaw)\
**Replies:** 0\
**Last updated:** [October 29, 2020, 6:16pm UTC](https://discourse.julialang.org/t/avoid-getting-a-reshapedarray-when-calling-reshape/49255 "2020-10-29T18:16:09Z")

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Flux has the clever array type Zeros for which arithmetic operations are implemented as basically noops (well, I guess you get the idea). The main use case is to turn of the bias term but the problem is that some ops ne…

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