# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=519

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

**Page:** 520

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## [Pure Julia FFT](https://discourse.julialang.org/t/pure-julia-fft/17180)

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**Author:** [@bdeonovic](https://discourse.julialang.org/u/bdeonovic)\
**Replies:** 1\
**Last updated:** [November 5, 2018, 5:20pm UTC](https://discourse.julialang.org/t/pure-julia-fft/17180 "2018-11-05T17:20:03Z")

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@stevengj I was told you are working on a pure julia FFT. Any updates on this endeavor?

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## [Censored regression and IV models?](https://discourse.julialang.org/t/censored-regression-and-iv-models/17150)

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**Author:** [@iwelch](https://discourse.julialang.org/u/iwelch)\
**Replies:** 6\
**Last updated:** [November 5, 2018, 3:57pm UTC](https://discourse.julialang.org/t/censored-regression-and-iv-models/17150 "2018-11-05T15:57:51Z")

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Does julia already have a package suited to censored regression models, as in Tobit model - Wikipedia ? (PS: InstrumentalVariables? Giuseppe Ragusa’s package is no longer working—and it is not in the repository, either…

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## [Julia novice. Integer programming code optimization error](https://discourse.julialang.org/t/julia-novice-integer-programming-code-optimization-error/6926)

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**Author:** [@yold6](https://discourse.julialang.org/u/yold6)\
**Replies:** 4\
**Last updated:** [November 5, 2018, 4:43am UTC](https://discourse.julialang.org/t/julia-novice-integer-programming-code-optimization-error/6926 "2018-11-05T04:43:52Z")

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Hello and thanks for reading this. I am new to Julia and am attempting to use JuMP to generate entries for Fanduel football tournament contests with a top heavy payoff structure. The code are my modifications to code ori…

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## [Drastic performance hit matrix multiply different types. Internal cast julia vs numpy?](https://discourse.julialang.org/t/drastic-performance-hit-matrix-multiply-different-types-internal-cast-julia-vs-numpy/17120)

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**Author:** [@davidbp](https://discourse.julialang.org/u/davidbp)\
**Replies:** 15\
**Last updated:** [November 4, 2018, 7:48am UTC](https://discourse.julialang.org/t/drastic-performance-hit-matrix-multiply-different-types-internal-cast-julia-vs-numpy/17120 "2018-11-04T07:48:00Z")

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Because of several performance problems I have seen in discourse I wanted to ask why this is happening. And how is it possible it is not happening in numpy? I know we can avoid the problem I present here beeing careful…

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## [Space indices can now be fetch automatically in SatelliteToolbox.jl](https://discourse.julialang.org/t/space-indices-can-now-be-fetch-automatically-in-satellitetoolbox-jl/17100)

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**Author:** [@Ronis\_BR](https://discourse.julialang.org/u/Ronis_BR)\
**Replies:** 1\
**Last updated:** [November 2, 2018, 8:25pm UTC](https://discourse.julialang.org/t/space-indices-can-now-be-fetch-automatically-in-satellitetoolbox-jl/17100 "2018-11-02T20:25:10Z")

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Hi guys! I have just pushed a lot of modifications to SatelliteToolbox.jl. I added the support for fetching space indices that are required to compute atmospheric models. Right now, we have support to get these indices: …

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## [Data files with 'quotes' around the column names](https://discourse.julialang.org/t/data-files-with-quotes-around-the-column-names/17067)

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**Author:** [@GlenHenshaw](https://discourse.julialang.org/u/GlenHenshaw)\
**Replies:** 6\
**Last updated:** [November 2, 2018, 12:21am UTC](https://discourse.julialang.org/t/data-files-with-quotes-around-the-column-names/17067 "2018-11-02T00:21:48Z")

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I have data files, given to me by someone else, with the following format: 'col1','col2','col3' 1,2,3 4,5,6 And so on. CSV reads them just fine, and leaves me with a DataFrame that looks like |Row | 'col1' | 'col…

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## [How to use channel to communicate with a process](https://discourse.julialang.org/t/how-to-use-channel-to-communicate-with-a-process/17074)

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**Author:** [@Alexander-Barth](https://discourse.julialang.org/u/Alexander-Barth)\
**Replies:** 0\
**Last updated:** [November 1, 2018, 9:35pm UTC](https://discourse.julialang.org/t/how-to-use-channel-to-communicate-with-a-process/17074 "2018-11-01T21:35:50Z")

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I try to run a function with @span and get some status back on the computation using e.g. a Channel before I get the end-result. The following code already works, but I am new to channels and I am wondering if there is a…

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## [How to draw a rectangular region with Plots.jl?](https://discourse.julialang.org/t/how-to-draw-a-rectangular-region-with-plots-jl/1719)

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**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\
**Replies:** 7\
**Last updated:** [November 1, 2018, 8:39pm UTC](https://discourse.julialang.org/t/how-to-draw-a-rectangular-region-with-plots-jl/1719 "2018-11-01T20:39:44Z")

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For an example in PyPlot: http://matthiaseisen.com/pp/patterns/p0203/

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## [Help with a Constraint](https://discourse.julialang.org/t/help-with-a-constraint/13827)

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**Author:** [@muriloasouza](https://discourse.julialang.org/u/muriloasouza)\
**Replies:** 15\
**Last updated:** [November 1, 2018, 1:37pm UTC](https://discourse.julialang.org/t/help-with-a-constraint/13827 "2018-11-01T13:37:35Z")

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Hello, I need some help to write a constraint for my problem. This constraint has the following matrix: using JuMP, CouenneNL Nt = 2; L = 0; C = 0; h = 0; hmax = 5; Y = zeros(Nt,Nt,hmax); b = 2; v = 10; for h = 3:2:…

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## [Question on array of SVectors and \\](https://discourse.julialang.org/t/question-on-array-of-svectors-and/17010)

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**Author:** [@cserteGT3](https://discourse.julialang.org/u/cserteGT3)\
**Replies:** 2\
**Last updated:** [October 31, 2018, 8:01pm UTC](https://discourse.julialang.org/t/question-on-array-of-svectors-and/17010 "2018-10-31T20:01:57Z")

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I’m learning about ICP (Iterative Closest Point) and at this stage try to implement the basics myself (I know about the existing packages). I have two arrays of points, that I want to match and therefore I want to compu…

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## [Help with Tag type parameter in ForwardDiff.jl (+ Optim.jl)](https://discourse.julialang.org/t/help-with-tag-type-parameter-in-forwarddiff-jl-optim-jl/16969)

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**Author:** [@skarp](https://discourse.julialang.org/u/skarp)\
**Replies:** 6\
**Last updated:** [October 31, 2018, 2:45pm UTC](https://discourse.julialang.org/t/help-with-tag-type-parameter-in-forwarddiff-jl-optim-jl/16969 "2018-10-31T14:45:33Z")

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Hello. I understand from the documentation of ForwardDiff.jl that the package uses a Tag type parameter to avoid something called ‘perturbation confusion’: http://www.juliadiff.org/ForwardDiff.jl/stable/dev/how\_it\_work…

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## [Use of StatsModels?](https://discourse.julialang.org/t/use-of-statsmodels/16979)

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**Author:** [@mcreel](https://discourse.julialang.org/u/mcreel)\
**Replies:** 7\
**Last updated:** [October 31, 2018, 12:44pm UTC](https://discourse.julialang.org/t/use-of-statsmodels/16979 "2018-10-31T12:44:05Z")

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I’m interested in making some of my modeling functions accept dataframes and fomulae as inputs, using the StatsModels package. Is the following the proper way to achieve this? My plan would be to do something like usin…

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## [Avoiding JIT Compilation of Remotecall Functions](https://discourse.julialang.org/t/avoiding-jit-compilation-of-remotecall-functions/15904)

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**Author:** [@rohanmclure](https://discourse.julialang.org/u/rohanmclure)\
**Replies:** 2\
**Last updated:** [October 31, 2018, 5:29am UTC](https://discourse.julialang.org/t/avoiding-jit-compilation-of-remotecall-functions/15904 "2018-10-31T05:29:49Z")

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I am implementing a distributed transpose kernel which depends on distributing an array by means of generating equal sized ‘subarrays’ of the whole, distributing them to my worker processes and then performing a remoteca…

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## [Gurobi fail to precompile](https://discourse.julialang.org/t/gurobi-fail-to-precompile/16993)

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**Author:** [@Ksun46](https://discourse.julialang.org/u/Ksun46)\
**Replies:** 0\
**Last updated:** [October 31, 2018, 4:46am UTC](https://discourse.julialang.org/t/gurobi-fail-to-precompile/16993 "2018-10-31T04:46:09Z")

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I didn’t call Gurobi for a long time. It used to work find. But today when I did, I got this INFO: Precompiling module Gurobi. WARNING: Module Compat with uuid 1366427411356359 is missing from the cache. This may mean m…

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## [How to store joint transform while running simulation in RigidBodyDynamics.jl](https://discourse.julialang.org/t/how-to-store-joint-transform-while-running-simulation-in-rigidbodydynamics-jl/16797)

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**Author:** [@HiroIshida](https://discourse.julialang.org/u/HiroIshida)\
**Replies:** 5\
**Last updated:** [October 31, 2018, 1:54am UTC](https://discourse.julialang.org/t/how-to-store-joint-transform-while-running-simulation-in-rigidbodydynamics-jl/16797 "2018-10-31T01:54:48Z")

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Does anyone know how to store joint transform while running a simulation in RigidBodyDynamics.jl? I know that getting a joint transform before and after simulate() by using joint\_transform(). But, I don’t know how to do …

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## [File IO - Parquet File Reader](https://discourse.julialang.org/t/file-io-parquet-file-reader/15496)

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**Author:** [@mdsalerno](https://discourse.julialang.org/u/mdsalerno)\
**Replies:** 4\
**Last updated:** [October 30, 2018, 9:24pm UTC](https://discourse.julialang.org/t/file-io-parquet-file-reader/15496 "2018-10-30T21:24:26Z")

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Is there a Julia v1.0 supported parquet file reader that can be used to load into a DataFrame? I attempted to use the example on Queryverse.jl but it seems it requires ParquetFiles.jl. I get the following when I try to…

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## [TextParse.jl is fast again](https://discourse.julialang.org/t/textparse-jl-is-fast-again/16664)

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**Author:** [@davidanthoff](https://discourse.julialang.org/u/davidanthoff)\
**Replies:** 13\
**Last updated:** [October 29, 2018, 6:41pm UTC](https://discourse.julialang.org/t/textparse-jl-is-fast-again/16664 "2018-10-29T18:41:31Z")

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Some of you might have noticed that TextParse.jl (and CSVFiles.jl, which is a small wrapper around TextParse.jl) saw some major performance regressions initially on julia 1.0. I just fixed these and now both packages ar…

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## [Semi-infinite programming with JuMP](https://discourse.julialang.org/t/semi-infinite-programming-with-jump/16953)

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**Author:** [@Azzaare](https://discourse.julialang.org/u/Azzaare)\
**Replies:** 1\
**Last updated:** [October 30, 2018, 7:59am UTC](https://discourse.julialang.org/t/semi-infinite-programming-with-jump/16953 "2018-10-30T07:59:43Z")

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Hi there, I was wondering if there is any plan to have some semi-infinite solver interfaced through JuMP at some point (for instance NSIPS). I suppose it is not the case, but it doesn’t hurt to ask :wink:

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## [Porting a RNN model to Flux from PyTorch](https://discourse.julialang.org/t/porting-a-rnn-model-to-flux-from-pytorch/16487)

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**Author:** [@sdwfrost](https://discourse.julialang.org/u/sdwfrost)\
**Replies:** 5\
**Last updated:** [October 29, 2018, 12:04pm UTC](https://discourse.julialang.org/t/porting-a-rnn-model-to-flux-from-pytorch/16487 "2018-10-29T12:04:19Z")

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Hi All, I’m trying to port this example of a recurrent neural network in PyTorch to Flux to help me learn the API. I know that I’m not putting the data together with the loss function in the right way (I’m using the cha…

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## [Flux.jl RNN performance](https://discourse.julialang.org/t/flux-jl-rnn-performance/16803)

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**Author:** [@ak168421](https://discourse.julialang.org/u/ak168421)\
**Replies:** 11\
**Last updated:** [October 28, 2018, 10:18pm UTC](https://discourse.julialang.org/t/flux-jl-rnn-performance/16803 "2018-10-28T22:18:36Z")

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I have been trying out Flux.jl for RNNs and I really like the syntax. I am wondering how I should expect performance to compare to, say PyTorch and whether there are things I should look out for in terms of defining mode…

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## [PGFPlotsX and color map](https://discourse.julialang.org/t/pgfplotsx-and-color-map/16868)

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**Author:** [@PetrKryslUCSD](https://discourse.julialang.org/u/PetrKryslUCSD)\
**Replies:** 9\
**Last updated:** [October 28, 2018, 5:08pm UTC](https://discourse.julialang.org/t/pgfplotsx-and-color-map/16868 "2018-10-28T17:08:08Z")

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I want to use a different color map than “hot”. When I try to use the “viridis” color map, I get an error. It isn’t clear to me why it should be so, since the latex code matches what I can find in the PGF manual. @pgf …

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## [Julia 0.7 flattening of Nested Tuples](https://discourse.julialang.org/t/julia-0-7-flattening-of-nested-tuples/16860)

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**Author:** [@Ultima](https://discourse.julialang.org/u/Ultima)\
**Replies:** 1\
**Last updated:** [October 28, 2018, 4:01pm UTC](https://discourse.julialang.org/t/julia-0-7-flattening-of-nested-tuples/16860 "2018-10-28T16:01:09Z")

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I’ve implemented a Julia Version of a “Multiplicative Partitions of a Number”. Since 0.7 the State, start … iteration changed. I got a pre 0.7 Version of a Tuple flattener on this Page: Nested list comprehensions in Juli…

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## [Gadfly SVGs render without color](https://discourse.julialang.org/t/gadfly-svgs-render-without-color/16804)

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**Author:** [@hellemo](https://discourse.julialang.org/u/hellemo)\
**Replies:** 8\
**Last updated:** [October 28, 2018, 2:08pm UTC](https://discourse.julialang.org/t/gadfly-svgs-render-without-color/16804 "2018-10-28T14:08:27Z")

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I just updated some code to work with v1.0 of Julia and Gadfly, and the SVG output from Gadfly that used to work fine with MS Office now renders without color, the svg editor Inkscape also renders it with no color. usin…

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## [Interact.jl: plot as widget?](https://discourse.julialang.org/t/interact-jl-plot-as-widget/16736)

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**Author:** [@bjarthur](https://discourse.julialang.org/u/bjarthur)\
**Replies:** 3\
**Last updated:** [October 27, 2018, 2:34pm UTC](https://discourse.julialang.org/t/interact-jl-plot-as-widget/16736 "2018-10-27T14:34:02Z")

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with interact.jl one can create widgets which can then change a plot. i want to click on a plot, get the x,y coordinates of where i clicked, and then generate/modify a second plot. immerse.jl could probably do this via…

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## [Possible issue with zeta function](https://discourse.julialang.org/t/possible-issue-with-zeta-function/16802)

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**Author:** [@ArchieCall](https://discourse.julialang.org/u/ArchieCall)\
**Replies:** 3\
**Last updated:** [October 27, 2018, 5:45am UTC](https://discourse.julialang.org/t/possible-issue-with-zeta-function/16802 "2018-10-27T05:45:29Z")

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I have noticed an issue when using the zeta function that is supplied by the SpecialFunctions package. Specifically, it outputs a NaN for a certain range of imaginary values. using SpecialFunctions zeta1 = zeta(.4 + 45…

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## [Article that explains using Flux on MNIST from the model-zoo example](https://discourse.julialang.org/t/article-that-explains-using-flux-on-mnist-from-the-model-zoo-example/16295)

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**Author:** [@microgold](https://discourse.julialang.org/u/microgold)\
**Replies:** 4\
**Last updated:** [October 27, 2018, 5:24am UTC](https://discourse.julialang.org/t/article-that-explains-using-flux-on-mnist-from-the-model-zoo-example/16295 "2018-10-27T05:24:43Z")

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I created an article that attempts to explain the Flux example of a Convolutional Neural Network operating on the MNIST set. The article goes through each line and explains what its doing in Julia. I’d appreciate any i…

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## [Inconsistency between standard errors from Hessian and Gradient in ForwardDiff/Optim](https://discourse.julialang.org/t/inconsistency-between-standard-errors-from-hessian-and-gradient-in-forwarddiff-optim/16769)

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**Author:** [@cosmia](https://discourse.julialang.org/u/cosmia)\
**Replies:** 6\
**Last updated:** [October 26, 2018, 11:12pm UTC](https://discourse.julialang.org/t/inconsistency-between-standard-errors-from-hessian-and-gradient-in-forwarddiff-optim/16769 "2018-10-26T23:12:04Z")

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I have been using Optim package with AD recently, and I am having some strange behaviour with the gradient. I am using Optim and NLSolversBase in the context of Maximum Likelihood Estimation, and passing a TwiceDifferent…

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## [RigidBodySim.jl and disturbances](https://discourse.julialang.org/t/rigidbodysim-jl-and-disturbances/16576)

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**Author:** [@phelipe](https://discourse.julialang.org/u/phelipe)\
**Replies:** 5\
**Last updated:** [October 26, 2018, 1:57pm UTC](https://discourse.julialang.org/t/rigidbodysim-jl-and-disturbances/16576 "2018-10-26T13:57:29Z")

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Hi, is there any way to add friction or other disturbance to the model as the controller is added? Something like: closed\_loop\_dynamics = Dynamics(robot, control!, disturbance!)

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## [Assertion error with MOI.initialize(d, \[:Grad\])](https://discourse.julialang.org/t/assertion-error-with-moi-initialize-d-grad/16796)

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**Author:** [@chkwon](https://discourse.julialang.org/u/chkwon)\
**Replies:** 1\
**Last updated:** [October 26, 2018, 12:39pm UTC](https://discourse.julialang.org/t/assertion-error-with-moi-initialize-d-grad/16796 "2018-10-26T12:39:05Z")

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I’m on JuMP#v0.19-alpha. using JuMP plants = \["seattle", "san-diego"\] markets = \["new-york", "chicago", "topeka"\] distance = \[ 2.5 1.7 1.8 ; 2.5 1.8 1.4 \] d = Dict() for i in 1:length(plants), j in 1:leng…

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## [Sensitivity (post-optimality) analysis of a linear model?](https://discourse.julialang.org/t/sensitivity-post-optimality-analysis-of-a-linear-model/16785)

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**Author:** [@amca01](https://discourse.julialang.org/u/amca01)\
**Replies:** 2\
**Last updated:** [October 25, 2018, 11:32pm UTC](https://discourse.julialang.org/t/sensitivity-post-optimality-analysis-of-a-linear-model/16785 "2018-10-25T23:32:44Z")

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I have been experimenting with simple LP problems using JuMP and the solvers CbcSolver and GLPKSolverLP. (I’d like to try ClpSolver but I keep getting errors when I try to build it.) Now I can solve my models fine, but…

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