# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=564

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**Page:** 565

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## [Basic cycles in a un-directed gaph](https://discourse.julialang.org/t/basic-cycles-in-a-un-directed-gaph/2835)

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**Author:** [@TsurHerman](https://discourse.julialang.org/u/TsurHerman)\
**Replies:** 3\
**Last updated:** [March 23, 2017, 4:44pm UTC](https://discourse.julialang.org/t/basic-cycles-in-a-un-directed-gaph/2835 "2017-03-23T16:44:47Z")

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I have a situation that can be reduced to finding basic cycles in an undirected graph of length 4(the cycles require to be length 4) I don’t have much previous experience with graphs, but this seems a simple operation …

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## [Issues with JuMPeR](https://discourse.julialang.org/t/issues-with-jumper/2794)

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**Author:** [@Shimrit\_Shtern](https://discourse.julialang.org/u/Shimrit_Shtern)\
**Replies:** 5\
**Last updated:** [March 23, 2017, 3:39pm UTC](https://discourse.julialang.org/t/issues-with-jumper/2794 "2017-03-23T15:39:07Z")

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Hi I have a legacy code in JuMPeR which I’m trying to run with the latest version of JuMP and Julia. The command setDefaultOracle is not recognized, and I can not find what it was changed to. Does anybody know what it …

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## [Equivalent Julia package to R package \`prob\`](https://discourse.julialang.org/t/equivalent-julia-package-to-r-package-prob/2829)

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**Author:** [@AjayTalati](https://discourse.julialang.org/u/AjayTalati)\
**Replies:** 9\
**Last updated:** [March 23, 2017, 2:56pm UTC](https://discourse.julialang.org/t/equivalent-julia-package-to-r-package-prob/2829 "2017-03-23T14:56:13Z")

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Hello :slight\_smile:, I’m new to Julia, and have been using R previously. Could I ask if there’s an equivalent package in Julia to the package, prob in R. https://cran.r-project.org/web/packages/prob/vignettes/prob.pdf …

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## [Cannot collect variables with index not starting from 1 in a vector](https://discourse.julialang.org/t/cannot-collect-variables-with-index-not-starting-from-1-in-a-vector/2739)

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**Author:** [@Wei\_Wang](https://discourse.julialang.org/u/Wei_Wang)\
**Replies:** 5\
**Last updated:** [March 22, 2017, 8:51pm UTC](https://discourse.julialang.org/t/cannot-collect-variables-with-index-not-starting-from-1-in-a-vector/2739 "2017-03-22T20:51:09Z")

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Hi, I am trying to create anonymous variables and collect them in a vector. But only those with index starting from 1 can be collected. Others will result in error. Is there any method to push those variables into a vec…

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## [Is there a dropna() for DataFrame?](https://discourse.julialang.org/t/is-there-a-dropna-for-dataframe/1777)

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**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\
**Replies:** 23\
**Last updated:** [March 22, 2017, 2:11pm UTC](https://discourse.julialang.org/t/is-there-a-dropna-for-dataframe/1777 "2017-03-22T14:11:47Z")

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How to drop the rows of a DataFrame that contain NA in any column? dropna() apparently only works with DataArray?

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## [Julia Plots.jl with plotlyJS backend pauses on every call to savefig](https://discourse.julialang.org/t/julia-plots-jl-with-plotlyjs-backend-pauses-on-every-call-to-savefig/2787)

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**Author:** [@colintbowers](https://discourse.julialang.org/u/colintbowers)\
**Replies:** 4\
**Last updated:** [March 22, 2017, 12:52am UTC](https://discourse.julialang.org/t/julia-plots-jl-with-plotlyjs-backend-pauses-on-every-call-to-savefig/2787 "2017-03-22T00:52:14Z")

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Hi all, I’m getting the following issue when attempting to use savefig() with the Plots.jl package and plotlyjs() backend (note, Julia v0.5.0, Plots.jl v0.10.3, PlotlyJS.jl v0.5.2, Blink v0.5.1, on Ubuntu 16.04) . Oddly…

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## [Call for bikeshedding: Updated ParameterizedFunction Syntax](https://discourse.julialang.org/t/call-for-bikeshedding-updated-parameterizedfunction-syntax/2738)

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**Author:** [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)\
**Replies:** 11\
**Last updated:** [March 20, 2017, 2:49pm UTC](https://discourse.julialang.org/t/call-for-bikeshedding-updated-parameterizedfunction-syntax/2738 "2017-03-20T14:49:13Z")

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I know people like bikeshedding syntax :slight\_smile:. I am looking to update the syntax for the macros in DifferentialEquations.jl (ParameterizedFunctions.jl) for “easily defining diffeqs”. I am looking for a syntax tha…

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## [An elegant way to construct recursive objective?](https://discourse.julialang.org/t/an-elegant-way-to-construct-recursive-objective/2503)

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**Author:** [@xqrongm](https://discourse.julialang.org/u/xqrongm)\
**Replies:** 5\
**Last updated:** [March 20, 2017, 4:33am UTC](https://discourse.julialang.org/t/an-elegant-way-to-construct-recursive-objective/2503 "2017-03-20T04:33:51Z")

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I need to fit a model on a vector f of length n, where f\[i\] is recursively calculated from f\[i-1\]. There is another vector d of length n related to f in the following way: f\[i\] = f0 + d\[i\] d\[1\] = d0 + k \* log(1 + d0 / k…

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## [Interested in Summer of Code](https://discourse.julialang.org/t/interested-in-summer-of-code/2337)

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**Author:** [@americast](https://discourse.julialang.org/u/americast)\
**Replies:** 6\
**Last updated:** [March 18, 2017, 11:59am UTC](https://discourse.julialang.org/t/interested-in-summer-of-code/2337 "2017-03-18T11:59:48Z")

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Hello everyone, I am interested in applying for Google Summer of Code as a student this year under Julia. I would like to work on building a package similar to BinDeps, which would enable us to create data providing pac…

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## [RE: GSoC - Interactivity and visualization tools](https://discourse.julialang.org/t/re-gsoc-interactivity-and-visualization-tools/2742)

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**Author:** [@MA\_Laforge](https://discourse.julialang.org/u/MA_Laforge)\
**Replies:** 1\
**Last updated:** [March 17, 2017, 9:27pm UTC](https://discourse.julialang.org/t/re-gsoc-interactivity-and-visualization-tools/2742 "2017-03-17T21:27:44Z")

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Not sure where else to add a comment: I would like to add another interesting Python-based reference tool to the mix: guiqwt: GitHub - PlotPyStack/guiqwt: Efficient 2D plotting Python library based on PythonQwt It app…

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## [CUDAnative on macOS X](https://discourse.julialang.org/t/cudanative-on-macos-x/2671)

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**Author:** [@jheinen](https://discourse.julialang.org/u/jheinen)\
**Replies:** 13\
**Last updated:** [March 17, 2017, 6:05pm UTC](https://discourse.julialang.org/t/cudanative-on-macos-x/2671 "2017-03-17T18:05:54Z")

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Did anyone manage to get CUDAnative running on macOS X? I could successfully install CUDAdrv … push!(Libdl.DL\_LOAD\_PATH, "/usr/local/cuda/lib") Pkg.add("CUDAdrv") … but trying to add CUDAnative fails with LLVM errors:…

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## [Eigs and cryptic arparck errors](https://discourse.julialang.org/t/eigs-and-cryptic-arparck-errors/2722)

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**Author:** [@maarten\_van\_damme](https://discourse.julialang.org/u/maarten_van_damme)\
**Replies:** 4\
**Last updated:** [March 17, 2017, 4:33pm UTC](https://discourse.julialang.org/t/eigs-and-cryptic-arparck-errors/2722 "2017-03-17T16:33:50Z")

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I’m trying to use eigs and I’m running into arparck errors. More specifically, when eigs doesn’t converge the function itself doesn’t throw or return some kind of flag (even though that is what the documentation seemed t…

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## [Plots.jl - No method matching expand\_extrema](https://discourse.julialang.org/t/plots-jl-no-method-matching-expand-extrema/2717)

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**Author:** [@josimar](https://discourse.julialang.org/u/josimar)\
**Replies:** 1\
**Last updated:** [March 17, 2017, 5:25am UTC](https://discourse.julialang.org/t/plots-jl-no-method-matching-expand-extrema/2717 "2017-03-17T05:25:58Z")

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Hi, I am using the Plots.jl with the GR backend. I am trying to make the following plot: plot( SSE\[1\].Mag, SSE\[1\].N ) Where both SSE\[1\].Mag and SSE\[1\].N are of types Array{Any,1} However, I am getting the error below…

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## [Issue with Julia MPC Out of Bounds Error](https://discourse.julialang.org/t/issue-with-julia-mpc-out-of-bounds-error/2720)

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**Author:** [@Angshuman\_Goswami](https://discourse.julialang.org/u/Angshuman_Goswami)\
**Replies:** 1\
**Last updated:** [March 16, 2017, 10:57pm UTC](https://discourse.julialang.org/t/issue-with-julia-mpc-out-of-bounds-error/2720 "2017-03-16T22:57:57Z")

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\#!/usr/bin/env julia #= \*\* Licensing Information: You are free to use or extend these projects for \*\* \*\* education or research purposes provided that (1) you retain this notice\*\* \*\* and (2) you provide clear attribut…

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## [Dense gridlines in Plots.jl](https://discourse.julialang.org/t/dense-gridlines-in-plots-jl/1499)

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**Author:** [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Replies:** 4\
**Last updated:** [March 16, 2017, 12:41pm UTC](https://discourse.julialang.org/t/dense-gridlines-in-plots-jl/1499 "2017-03-16T12:41:48Z")

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In a MWE using Plots x = Date(1990,1):Dates.Month(1):Date(2016,1) y = \[rand()+1.0 for \_ in x\] plot(x, y) how could I get vertical grid lines at every year (eg on Jan 1) or every 5 years in the plot? Using various backe…

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## [Need some pointers to implement scheme based routing](https://discourse.julialang.org/t/need-some-pointers-to-implement-scheme-based-routing/2678)

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**Author:** [@Sarvjeet](https://discourse.julialang.org/u/Sarvjeet)\
**Replies:** 0\
**Last updated:** [March 15, 2017, 1:53pm UTC](https://discourse.julialang.org/t/need-some-pointers-to-implement-scheme-based-routing/2678 "2017-03-15T13:53:16Z")

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I have made a pull request here implementing scheme based routing in Mux. I don’t know how to test it (details are mentioned in the pull request), could someone please take a look at it. Thanks in advance.

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## [Showing a captured video sequence with annotations](https://discourse.julialang.org/t/showing-a-captured-video-sequence-with-annotations/2625)

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**Author:** [@TsurHerman](https://discourse.julialang.org/u/TsurHerman)\
**Replies:** 21\
**Last updated:** [March 15, 2017, 9:44am UTC](https://discourse.julialang.org/t/showing-a-captured-video-sequence-with-annotations/2625 "2017-03-15T09:44:53Z")

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Hi , For debugging an object tracking system, I need to be able to display captured images and to easily annotate those images with text. I am looking for a solution that is not dependent on openCV. I don’t care abou…

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## [Dropout in mxnet](https://discourse.julialang.org/t/dropout-in-mxnet/2667)

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**Author:** [@Patrik\_Waldmann](https://discourse.julialang.org/u/Patrik_Waldmann)\
**Replies:** 0\
**Last updated:** [March 14, 2017, 7:31pm UTC](https://discourse.julialang.org/t/dropout-in-mxnet/2667 "2017-03-14T19:31:10Z")

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I’m trying to understand how to use dropout in mxnet and start with a simple regression example: #= Regression with dropout =# using MXNet # create training and evaluation data sets url = "https://archive.ics.uci.edu/m…

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## [Issue Solving BQPs with JuMP+CPLEX](https://discourse.julialang.org/t/issue-solving-bqps-with-jump-cplex/2624)

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**Author:** [@omalled](https://discourse.julialang.org/u/omalled)\
**Replies:** 8\
**Last updated:** [March 14, 2017, 5:17pm UTC](https://discourse.julialang.org/t/issue-solving-bqps-with-jump-cplex/2624 "2017-03-14T17:17:34Z")

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I am having some trouble solving binary quadratic programs with JuMP and CPLEX. Here is some code that illustrates the problem: import JuMP import CPLEX function bqp(Q, c) m = JuMP.Model(solver=CPLEX.CplexSolver()) @…

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## [What data structure to use to hold large categorial dataset for analytics?](https://discourse.julialang.org/t/what-data-structure-to-use-to-hold-large-categorial-dataset-for-analytics/2646)

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**Author:** [@ilanggear](https://discourse.julialang.org/u/ilanggear)\
**Replies:** 3\
**Last updated:** [March 14, 2017, 8:53am UTC](https://discourse.julialang.org/t/what-data-structure-to-use-to-hold-large-categorial-dataset-for-analytics/2646 "2017-03-14T08:53:12Z")

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I have a dataset that is approximately 1 million rows by 40 columns of mostly categorical values, and I need to hold it in memory while I build indexes (themselves needing lots of memory) and do some ad-hoc analytics on …

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## [Is there any function to get the number of remaining messages in AWS SQS queue?](https://discourse.julialang.org/t/is-there-any-function-to-get-the-number-of-remaining-messages-in-aws-sqs-queue/2653)

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**Author:** [@jwu](https://discourse.julialang.org/u/jwu)\
**Replies:** 0\
**Last updated:** [March 14, 2017, 3:26am UTC](https://discourse.julialang.org/t/is-there-any-function-to-get-the-number-of-remaining-messages-in-aws-sqs-queue/2653 "2017-03-14T03:26:57Z")

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or just whether it is empty or not. I did not find any function in AWS.jl try catch is an alternative to tell whether the queue is empty or not, but seems not that clear.

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## [Evaluating explicitly the kernel for a Gaussian/Normal distribution](https://discourse.julialang.org/t/evaluating-explicitly-the-kernel-for-a-gaussian-normal-distribution/2632)

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**Author:** [@Bernal](https://discourse.julialang.org/u/Bernal)\
**Replies:** 1\
**Last updated:** [March 13, 2017, 9:02am UTC](https://discourse.julialang.org/t/evaluating-explicitly-the-kernel-for-a-gaussian-normal-distribution/2632 "2017-03-13T09:02:46Z")

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Hi folks, probably I’m attempting to discover “how to boil water” however I have faced some weird problems building a vector of values matching a Gaussian bell (I do NOT want to create a random variables vector that is…

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## [How does Loess decide how many sub-intervals to use for local regression?](https://discourse.julialang.org/t/how-does-loess-decide-how-many-sub-intervals-to-use-for-local-regression/2615)

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**Author:** [@KrishnaKanhaiya](https://discourse.julialang.org/u/KrishnaKanhaiya)\
**Replies:** 0\
**Last updated:** [March 12, 2017, 5:34am UTC](https://discourse.julialang.org/t/how-does-loess-decide-how-many-sub-intervals-to-use-for-local-regression/2615 "2017-03-12T05:34:05Z")

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Hi, I want to do local regression at each and every input point. For example: using Loess xs = sort(rand(100)) #100 input points p = 1 ys = exp(p\*tpoints) + 0.1 \* rand(100) model = loess(xs,ys) when I do model.bs …

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## [Using ApproxFun for dynamic programming](https://discourse.julialang.org/t/using-approxfun-for-dynamic-programming/1754)

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**Author:** [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Replies:** 11\
**Last updated:** [March 11, 2017, 11:41am UTC](https://discourse.julialang.org/t/using-approxfun-for-dynamic-programming/1754 "2017-03-11T11:41:02Z")

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I am wondering how to use ApproxFun for dynamic programming. I know the methods themselves very well, and I can easily implement a Chebyshev or spline basis and do everything from scratch, but it would be nice to use exi…

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## [DataTables : convert Nullable{String}("14:00:00") to Dates.Minute](https://discourse.julialang.org/t/datatables-convert-nullable-string-1400-to-dates-minute/2543)

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**Author:** [@Fred](https://discourse.julialang.org/u/Fred)\
**Replies:** 13\
**Last updated:** [March 11, 2017, 10:05am UTC](https://discourse.julialang.org/t/datatables-convert-nullable-string-1400-to-dates-minute/2543 "2017-03-11T10:05:32Z")

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Hi, I have a DataTable with two columns of time and I want to compute the time duration between these 2 columns. The problem I have is to compute a duration with Nullable type. julia\> a, b (Nullable{String}("14:00:00"…

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## [Error creating animation w/Plots.jl](https://discourse.julialang.org/t/error-creating-animation-w-plots-jl/2602)

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**Author:** [@Sean\_McBane](https://discourse.julialang.org/u/Sean_McBane)\
**Replies:** 2\
**Last updated:** [March 11, 2017, 7:33am UTC](https://discourse.julialang.org/t/error-creating-animation-w-plots-jl/2602 "2017-03-11T07:33:22Z")

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I am trying to make an animation using Plots.jl; the simple interface is really great. Unfortunately, it doesn’t work. It appears to be passing an invalid argument for ImageMagick. The error I get is: Invalid Parameter …

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## [Plotlyjs - animation errors in examples https://juliaplots.github.io/examples/plotlyjs/](https://discourse.julialang.org/t/plotlyjs-animation-errors-in-examples-https-juliaplots-github-io-examples-plotlyjs/2599)

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**Author:** [@olegmikul](https://discourse.julialang.org/u/olegmikul)\
**Replies:** 4\
**Last updated:** [March 11, 2017, 12:39am UTC](https://discourse.julialang.org/t/plotlyjs-animation-errors-in-examples-https-juliaplots-github-io-examples-plotlyjs/2599 "2017-03-11T00:39:00Z")

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Almost all example from https://juliaplots.github.io/examples/plotlyjs/ runs well under Jupyter notebook (some as is, some after minor Julia/Pkg fixes due to version updates). But 3 errors I can’t easy fix: Animation …

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## [Plotly - network error at opening a window from REPL, Jupyter is fine](https://discourse.julialang.org/t/plotly-network-error-at-opening-a-window-from-repl-jupyter-is-fine/2598)

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**Author:** [@olegmikul](https://discourse.julialang.org/u/olegmikul)\
**Replies:** 0\
**Last updated:** [March 10, 2017, 7:52pm UTC](https://discourse.julialang.org/t/plotly-network-error-at-opening-a-window-from-repl-jupyter-is-fine/2598 "2017-03-10T19:52:34Z")

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I am a new in plotlyjs. Works in Jupyter notebook, but not from REPL. From REPL it is opening a standalone window, wait for a while, and then showing: \*\*Network Error (tcp\_error) \*\* A communication error occurred: “Ope…

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## [Julia implementations of some of the foundational Machine Learning models and algorithms from scratch](https://discourse.julialang.org/t/julia-implementations-of-some-of-the-foundational-machine-learning-models-and-algorithms-from-scratch/2586)

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**Author:** [@memoiry](https://discourse.julialang.org/u/memoiry)\
**Replies:** 0\
**Last updated:** [March 10, 2017, 4:47am UTC](https://discourse.julialang.org/t/julia-implementations-of-some-of-the-foundational-machine-learning-models-and-algorithms-from-scratch/2586 "2017-03-10T04:47:54Z")

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Hi I have written a project https://github.com/memoiry/lightML.jl including basic implementation of typical machine learning algorithms implemented in Julia. It’s a self-educational project so that the implementation is…

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## [Modeling large dense LP with jump](https://discourse.julialang.org/t/modeling-large-dense-lp-with-jump/2557)

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**Author:** [@Pierre-Louis\_Poirion](https://discourse.julialang.org/u/Pierre-Louis_Poirion)\
**Replies:** 1\
**Last updated:** [March 9, 2017, 10:29pm UTC](https://discourse.julialang.org/t/modeling-large-dense-lp-with-jump/2557 "2017-03-09T22:29:30Z")

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Hi I am solve large dense LP (10^5 variables almost all coeff are non-zero) with jump and cplex. Now i am modeling the problem with the matrix: @constraint(m, A\*x==b) But it takes some time to create the model. Is t…

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