# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=513

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**Page:** 514

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## [Issues with shared memory parallel k-means implementation](https://discourse.julialang.org/t/issues-with-shared-memory-parallel-k-means-implementation/18894)

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**Author:** [@novoselrok](https://discourse.julialang.org/u/novoselrok)\
**Replies:** 1\
**Last updated:** [December 28, 2018, 4:34am UTC](https://discourse.julialang.org/t/issues-with-shared-memory-parallel-k-means-implementation/18894 "2018-12-28T04:34:25Z")

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Hello. I’m trying to implement the k-means algorithm using the @threads macro. I’ve also implemented a sequential program for comparison, but it always run faster than the parallel version. The changes to the parallel a…

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## [SatelliteToolbox.jl v0.5.0 has been tagged](https://discourse.julialang.org/t/satellitetoolbox-jl-v0-5-0-has-been-tagged/19039)

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**Author:** [@Ronis\_BR](https://discourse.julialang.org/u/Ronis_BR)\
**Replies:** 0\
**Last updated:** [December 27, 2018, 5:08pm UTC](https://discourse.julialang.org/t/satellitetoolbox-jl-v0-5-0-has-been-tagged/19039 "2018-12-27T17:08:30Z")

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Hi guys! I have just tagged the v0.5.0 of SatelliteToolbox.jl. This is a huge release (I think the biggest one of this package) that contains almost 2 months of work. Here is a summary of the changes (for a complete lis…

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## [Request for examples: Systems of nonlinear equations that have jacobians with special structure](https://discourse.julialang.org/t/request-for-examples-systems-of-nonlinear-equations-that-have-jacobians-with-special-structure/18936)

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**Author:** [@pkofod](https://discourse.julialang.org/u/pkofod)\
**Replies:** 1\
**Last updated:** [December 23, 2018, 8:43pm UTC](https://discourse.julialang.org/t/request-for-examples-systems-of-nonlinear-equations-that-have-jacobians-with-special-structure/18936 "2018-12-23T20:43:31Z")

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I’m changing some things in NLsolve.jl, in particular the possibility to chose the solver than solves the linear system of equations to determine the step direction. This means that if you have a package MySpecialLinsolv…

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## [Styling plotted maps](https://discourse.julialang.org/t/styling-plotted-maps/18673)

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**Author:** [@juliusgeo](https://discourse.julialang.org/u/juliusgeo)\
**Replies:** 5\
**Last updated:** [December 23, 2018, 5:55pm UTC](https://discourse.julialang.org/t/styling-plotted-maps/18673 "2018-12-23T17:55:32Z")

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Hi all, I am working on developing a package to create really nice looking plots of maps that are in OSM format. I currently am using Winston.jl, and just have a big dictionary containing all the styles that can be chan…

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## [How to use distance\_transform in Images.jl](https://discourse.julialang.org/t/how-to-use-distance-transform-in-images-jl/18861)

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**Author:** [@wrgr](https://discourse.julialang.org/u/wrgr)\
**Replies:** 2\
**Last updated:** [December 21, 2018, 8:21pm UTC](https://discourse.julialang.org/t/how-to-use-distance-transform-in-images-jl/18861 "2018-12-21T20:21:52Z")

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Tried to use distance\_transform(rand(Bool, 500, 500)) from Images.jl, but got MethodError: no method matching distance\_transform(::Array{Bool,2}) Closest candidates are: distance\_transform(!Matched::AbstractArray{Ca…

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## [GitLab CI for Julia GPU packages](https://discourse.julialang.org/t/gitlab-ci-for-julia-gpu-packages/11932)

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**Author:** [@maleadt](https://discourse.julialang.org/u/maleadt)\
**Replies:** 9\
**Last updated:** [December 21, 2018, 7:25pm UTC](https://discourse.julialang.org/t/gitlab-ci-for-julia-gpu-packages/11932 "2018-12-21T19:25:04Z")

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Hi all, I’ve been testing GitLab CI/CD for GPU-related packages, and despite some missing features it’s been a good experience and I’ve replaced my Buildbot set-up with it. The main advantage is that there is no need fo…

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## [Power Models Modification](https://discourse.julialang.org/t/power-models-modification/18874)

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**Author:** [@Rasoul](https://discourse.julialang.org/u/Rasoul)\
**Replies:** 2\
**Last updated:** [December 21, 2018, 4:12am UTC](https://discourse.julialang.org/t/power-models-modification/18874 "2018-12-21T04:12:55Z")

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Hi All, I want to modify “buspair\_parameters” function in PowerModels.ji to store parameters of all lines (including parallel lines) in the “buspair” dictionary. In other words, I want to store the parameters of each li…

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## [Whitespace issue with Gumbo.jl](https://discourse.julialang.org/t/whitespace-issue-with-gumbo-jl/18832)

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**Author:** [@mlhetland](https://discourse.julialang.org/u/mlhetland)\
**Replies:** 5\
**Last updated:** [December 20, 2018, 3:06pm UTC](https://discourse.julialang.org/t/whitespace-issue-with-gumbo-jl/18832 "2018-12-20T15:06:30Z")

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I realize this probably isn’t an issue with Gumbo.jl but rather with Gumbo itself (unless there’s some switch or something that’s not exposed) – or maybe even the HTML5 parsing algorithm – but I thought I’d see if someon…

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## [Announcement and call for talk proposals for the 3rd JuMP-dev workshop, Santiago, Chile, March, 2019](https://discourse.julialang.org/t/announcement-and-call-for-talk-proposals-for-the-3rd-jump-dev-workshop-santiago-chile-march-2019/17482)

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**Author:** [@joehuchette](https://discourse.julialang.org/u/joehuchette)\
**Replies:** 2\
**Last updated:** [December 20, 2018, 2:05pm UTC](https://discourse.julialang.org/t/announcement-and-call-for-talk-proposals-for-the-3rd-jump-dev-workshop-santiago-chile-march-2019/17482 "2018-12-20T14:05:13Z")

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Dear colleagues, We are excited to announce the third JuMP-dev workshop will take place in Santiago, Chile on March 12-14, 2019. The purpose of the workshop is to bring together students, researchers, and practitioners…

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## [JuMP 0.19-beta released (JuMP/MathOptInterface)](https://discourse.julialang.org/t/jump-0-19-beta-released-jump-mathoptinterface/18850)

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**Author:** [@miles.lubin](https://discourse.julialang.org/u/miles.lubin)\
**Replies:** 0\
**Last updated:** [December 20, 2018, 1:50pm UTC](https://discourse.julialang.org/t/jump-0-19-beta-released-jump-mathoptinterface/18850 "2018-12-20T13:50:10Z")

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Just in time for the holidays, we’re happy to announce that JuMP 0.19-beta is now released. We’re wrapping up the big transition to MathOptInterface (MOI) from MathProgBase. There are no more breaking changes planned for…

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## [Shrinkage prior in MixedModels](https://discourse.julialang.org/t/shrinkage-prior-in-mixedmodels/18801)

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**Author:** [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Replies:** 1\
**Last updated:** [December 19, 2018, 10:36pm UTC](https://discourse.julialang.org/t/shrinkage-prior-in-mixedmodels/18801 "2018-12-19T22:36:18Z")

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I would like to fit a hierarchical model Y \\sim X\\alpha + Z\\beta + \\epsilon\\\\ \\epsilon \\sim N(0,\\sigma^2\_\\epsilon) \\text{ iid}\\\\ \\alpha\_i \\sim N(\\mu\_\\alpha, \\sigma^2\_\\alpha)\\\\ \\beta\_i \\sim N(\\mu\_\\beta, \\sigma^2\_\\beta) …

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## [SharedArray example from documentation not working](https://discourse.julialang.org/t/sharedarray-example-from-documentation-not-working/18837)

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**Author:** [@mikkling](https://discourse.julialang.org/u/mikkling)\
**Replies:** 1\
**Last updated:** [December 19, 2018, 9:42pm UTC](https://discourse.julialang.org/t/sharedarray-example-from-documentation-not-working/18837 "2018-12-19T21:42:29Z")

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I’m trying to learn the intricacies of distributed computing, and was having troubles with SharedArrays not being available on workers. I went back to the documentation and tried the example. It threw the error below! I…

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## [add second order cone type constraint](https://discourse.julialang.org/t/add-second-order-cone-type-constraint/18742)

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**Author:** [@WangQuanmeng](https://discourse.julialang.org/u/WangQuanmeng)\
**Replies:** 4\
**Last updated:** [December 19, 2018, 2:28am UTC](https://discourse.julialang.org/t/add-second-order-cone-type-constraint/18742 "2018-12-19T02:28:39Z")

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Hi, I am new to Julia and JuMP, and I am learning to solve SOCP with integer constraint. The only example I can find online shows I should add the constraint in the following way. @constraint(m, norm(2x\[i\] - i for i=1…

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## ["Homomorphic machine learning" in Haskell; goal to be more generic and faster than Julia](https://discourse.julialang.org/t/homomorphic-machine-learning-in-haskell-goal-to-be-more-generic-and-faster-than-julia/18802)

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**Author:** [@datnamer](https://discourse.julialang.org/u/datnamer)\
**Replies:** 5\
**Last updated:** [December 19, 2018, 12:42am UTC](https://discourse.julialang.org/t/homomorphic-machine-learning-in-haskell-goal-to-be-more-generic-and-faster-than-julia/18802 "2018-12-19T00:42:56Z")

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https://github.com/mikeizbicki/HLearn " HLearn is also a research project. The research goal is to discover the “best possible” interface for machine learning. This involves two competing demands: The library should be …

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## [Poll: Do we Julians want ANOVAs?](https://discourse.julialang.org/t/poll-do-we-julians-want-anovas/3757)

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**Author:** [@LewisHein](https://discourse.julialang.org/u/LewisHein)\
**Replies:** 14\
**Last updated:** [December 18, 2018, 4:59pm UTC](https://discourse.julialang.org/t/poll-do-we-julians-want-anovas/3757 "2018-12-18T16:59:43Z")

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Hi everyone, I’m a scientist on a crusade. My crusade is to bring a really good ANOVA system to julia, probably by merging https://github.com/JuliaStats/GLM.jl/pull/70. I want to do this because Julia is awesome and I …

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## [DistributedArrays: basic element-wise vector operation is slow / fails](https://discourse.julialang.org/t/distributedarrays-basic-element-wise-vector-operation-is-slow-fails/18604)

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**Author:** [@samo](https://discourse.julialang.org/u/samo)\
**Replies:** 1\
**Last updated:** [December 18, 2018, 9:32am UTC](https://discourse.julialang.org/t/distributedarrays-basic-element-wise-vector-operation-is-slow-fails/18604 "2018-12-18T09:32:48Z")

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Hi all, I am new to Julia and did the following setup with DistributedArrays: julia -p 2 julia\> @everywhere using DistributedArrays julia\> nx = 6; julia\> A = zeros(nx-1); julia\> B = (1:nx).^2.0; julia\> A = distrib…

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## [Color Cycle Survey](https://discourse.julialang.org/t/color-cycle-survey/18704)

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**Author:** [@mpetroff](https://discourse.julialang.org/u/mpetroff)\
**Replies:** 10\
**Last updated:** [December 18, 2018, 11:00am UTC](https://discourse.julialang.org/t/color-cycle-survey/18704 "2018-12-18T11:00:53Z")

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For the past year or so, I’ve been working on techniques for generating visually pleasing colorblind-friendly color cycles, since I find the current Matplotlib default difficult to interpret (and it ends up in many of th…

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## [Question about LsqFit](https://discourse.julialang.org/t/question-about-lsqfit/18754)

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**Author:** [@yanyuechuixue](https://discourse.julialang.org/u/yanyuechuixue)\
**Replies:** 1\
**Last updated:** [December 18, 2018, 8:47am UTC](https://discourse.julialang.org/t/question-about-lsqfit/18754 "2018-12-18T08:47:32Z")

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Dear all, When I using LsqFit.curve\_fit, I encountered an error. the codes are: using LsqFit xdata = \[\[42.7908, 240.168, 32.799\], \[43.262, 346.383, -0.296673\], \[43.842, 332.0, -32.1631\] , \[44.184, 324.176, 35.19…

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## [Setting Flux custom gradients](https://discourse.julialang.org/t/setting-flux-custom-gradients/18728)

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**Author:** [@platawiec](https://discourse.julialang.org/u/platawiec)\
**Replies:** 6\
**Last updated:** [December 18, 2018, 8:24am UTC](https://discourse.julialang.org/t/setting-flux-custom-gradients/18728 "2018-12-18T08:24:24Z")

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I have been trying to make a Spatial Transformer Network in Flux (https://arxiv.org/pdf/1506.02025.pdf) mostly for my own education and because I think it would be slick to make one in Julia via Flux + Interpolations. I…

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## [Fail to do multiple linear regression using GLM](https://discourse.julialang.org/t/fail-to-do-multiple-linear-regression-using-glm/18780)

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**Author:** [@leejm516](https://discourse.julialang.org/u/leejm516)\
**Replies:** 7\
**Last updated:** [December 18, 2018, 8:13am UTC](https://discourse.julialang.org/t/fail-to-do-multiple-linear-regression-using-glm/18780 "2018-12-18T08:13:15Z")

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Hello, everybody. I have encountered doing multiple regression using GLM. Here’s my dataset data (originally come from Optimization of critical medium components using response surface methodology for ethanol productio…

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## [Yerror and ribbon not working in polar plots using Plots](https://discourse.julialang.org/t/yerror-and-ribbon-not-working-in-polar-plots-using-plots/18731)

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**Author:** [@babaq](https://discourse.julialang.org/u/babaq)\
**Replies:** 0\
**Last updated:** [December 17, 2018, 3:04am UTC](https://discourse.julialang.org/t/yerror-and-ribbon-not-working-in-polar-plots-using-plots/18731 "2018-12-17T03:04:20Z")

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In Plots, the polar projection seems not yet support yerror and ribbon, I am wandering if so, or I just missed something, or there are other way around?

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## [NLconstraint: equality, absolute value](https://discourse.julialang.org/t/nlconstraint-equality-absolute-value/18674)

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**Author:** [@jacob-roth](https://discourse.julialang.org/u/jacob-roth)\
**Replies:** 1\
**Last updated:** [December 17, 2018, 12:13am UTC](https://discourse.julialang.org/t/nlconstraint-equality-absolute-value/18674 "2018-12-17T00:13:50Z")

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I have a nonlinear, nonconvex equality constraint, and I only care about its magnitude. I saw this thread but wasn’t sure how to best handle the constraint in the nonconvex case. For example, I want something like: m = …

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## [Fastest open-licensed solver for integer problems](https://discourse.julialang.org/t/fastest-open-licensed-solver-for-integer-problems/17440)

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**Author:** [@vtjeng](https://discourse.julialang.org/u/vtjeng)\
**Replies:** 8\
**Last updated:** [December 16, 2018, 8:42pm UTC](https://discourse.julialang.org/t/fastest-open-licensed-solver-for-integer-problems/17440 "2018-12-16T20:42:21Z")

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I’m trying to compare solve times for a large mixed-integer linear problem on 1) Gurobi, 2) a fast open-licensed solver. I’m currently using Cbc.jl, but I’d like to know if there is another alternative that is significan…

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## [Drawing animated rectangles, circles, polygons etc...](https://discourse.julialang.org/t/drawing-animated-rectangles-circles-polygons-etc/18689)

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**Author:** [@chrisk](https://discourse.julialang.org/u/chrisk)\
**Replies:** 2\
**Last updated:** [December 15, 2018, 11:08pm UTC](https://discourse.julialang.org/t/drawing-animated-rectangles-circles-polygons-etc/18689 "2018-12-15T23:08:21Z")

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Hi, I’m a Julia beginner (I’m using Windows 10) and I’m looking for advice what package would be easy to use for drawing animated vector graphics. Background: I want to experiment with reinforcement learning and want t…

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## [New Linear Algebra Textbook (downloadable) Has JULIA Companion](https://discourse.julialang.org/t/new-linear-algebra-textbook-downloadable-has-julia-companion/18665)

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**Author:** [@sc0ttwad3](https://discourse.julialang.org/u/sc0ttwad3)\
**Replies:** 6\
**Last updated:** [December 15, 2018, 11:43am UTC](https://discourse.julialang.org/t/new-linear-algebra-textbook-downloadable-has-julia-companion/18665 "2018-12-15T11:43:51Z")

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If this hasn’t already been posted, a new Linear Algebra textbook has a great JULIA companion, lecture slides, and additional exercises from Stephen Boyd out of Stanford and Lieven Vandenberghe, is available for download…

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## [GPU kernel optimization (GPU vs CPU)](https://discourse.julialang.org/t/gpu-kernel-optimization-gpu-vs-cpu/18625)

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**Author:** [@Alexander-Barth](https://discourse.julialang.org/u/Alexander-Barth)\
**Replies:** 3\
**Last updated:** [December 14, 2018, 2:54pm UTC](https://discourse.julialang.org/t/gpu-kernel-optimization-gpu-vs-cpu/18625 "2018-12-14T14:54:09Z")

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I am new to CUDAnative.jl and I am trying to benchmark a very simple computational fluid dynamic model (based on the 1D linear shallow water equations). Essentially I get 3.228 s when I run the code on a CPU (i7-7700 CPU…

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## [GLM with weights](https://discourse.julialang.org/t/glm-with-weights/18603)

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**Author:** [@davidzentlermunro](https://discourse.julialang.org/u/davidzentlermunro)\
**Replies:** 6\
**Last updated:** [December 14, 2018, 11:16am UTC](https://discourse.julialang.org/t/glm-with-weights/18603 "2018-12-14T11:16:30Z")

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I’m getting the following error when trying to run GLM with a weight vector for my data: Julia Client – Internal Error DomainError(-1.867506166794264e-7, "sqrt will only return a complex result if called with a complex …

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## [Machine Learning Toolset Improvement](https://discourse.julialang.org/t/machine-learning-toolset-improvement/4835)

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**Author:** [@naveenjafer](https://discourse.julialang.org/u/naveenjafer)\
**Replies:** 10\
**Last updated:** [December 13, 2018, 7:06pm UTC](https://discourse.julialang.org/t/machine-learning-toolset-improvement/4835 "2018-12-13T19:06:19Z")

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Is there any consolidated set of machine learning packages available for Julia? I have spent some time trying to search for one, but have only come across JuliaML and it has not exactly been updated regularly. I would li…

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## [Show all linear constraints after building JuMP model](https://discourse.julialang.org/t/show-all-linear-constraints-after-building-jump-model/18536)

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**Author:** [@Rasoul](https://discourse.julialang.org/u/Rasoul)\
**Replies:** 5\
**Last updated:** [December 13, 2018, 2:16pm UTC](https://discourse.julialang.org/t/show-all-linear-constraints-after-building-jump-model/18536 "2018-12-13T14:16:22Z")

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Hi all, I want to visualize all linear constraint in my JuMP model. I used ( model.linconstr) command but it gives only a portion of my constraints. I have 454 constraints but (model.linconstr) shows only 36 of these co…

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## [Coloring Graphs with Lightgraphs](https://discourse.julialang.org/t/coloring-graphs-with-lightgraphs/18521)

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**Author:** [@AlexWue](https://discourse.julialang.org/u/AlexWue)\
**Replies:** 2\
**Last updated:** [December 13, 2018, 2:03pm UTC](https://discourse.julialang.org/t/coloring-graphs-with-lightgraphs/18521 "2018-12-13T14:03:19Z")

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Hi all, i am writing a paper in college about optimization problems in Julia. Regarding a network flow problem i would like to create a colored graph for visualization. I managed to visualize the nodes and edges with …

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