# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?page=561

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**Page:** 562

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## [TimeArray -\> {Regular,Irregular}TimeArray](https://discourse.julialang.org/t/timearray-regular-irregular-timearray/3919)

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**Author:** [@JeffreySarnoff](https://discourse.julialang.org/u/JeffreySarnoff)\
**Replies:** 0\
**Last updated:** [May 25, 2017, 6:50am UTC](https://discourse.julialang.org/t/timearray-regular-irregular-timearray/3919 "2017-05-25T06:50:05Z")

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TimeArray is the type underlying JuliaStats/TimeSeries. I need a slightly finer distinction and the ability to dispatch over each, RegularTimeArray (where deltaTime is constant) and IrregularTimeArray (where deltaTime i…

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## [Infeasibility Testing](https://discourse.julialang.org/t/infeasibility-testing/3910)

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**Author:** [@gopal2017](https://discourse.julialang.org/u/gopal2017)\
**Replies:** 3\
**Last updated:** [May 24, 2017, 6:47pm UTC](https://discourse.julialang.org/t/infeasibility-testing/3910 "2017-05-24T18:47:07Z")

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In CPLEX we have option to detect conflicting equations and/ check infeasibility of the model,if any. I am using Clp solver. Is there any option to do aforementioned task?

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## [Change of variable and constraint name](https://discourse.julialang.org/t/change-of-variable-and-constraint-name/3860)

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**Author:** [@gopal2017](https://discourse.julialang.org/u/gopal2017)\
**Replies:** 5\
**Last updated:** [May 24, 2017, 1:19pm UTC](https://discourse.julialang.org/t/change-of-variable-and-constraint-name/3860 "2017-05-24T13:19:19Z")

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Please let me know the way to change variable name and constraint name. We usually do it in CPLEX to change default name of variables and constraints to make it more meaningful and to give better understanding of .lp fil…

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## [Rotated cone constraint, how to include it?](https://discourse.julialang.org/t/rotated-cone-constraint-how-to-include-it/3879)

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**Author:** [@rayset](https://discourse.julialang.org/u/rayset)\
**Replies:** 2\
**Last updated:** [May 24, 2017, 12:13pm UTC](https://discourse.julialang.org/t/rotated-cone-constraint-how-to-include-it/3879 "2017-05-24T12:13:01Z")

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I’ve been trying for a few days to add the following constraint in jump: @NLconstraint(mod, R\[i,j,h\]^2 + T\[i,j,h\]^2 - 2\*u\_ijk\[i,i,j,h\]\*u\_ijk\[j,j,i,h\]\<=0) I tried every academic solver, but none is able to recognize t…

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## [Meaning of tetEdgeCrnrs and tetTri in marching\_tetrahedra.jl of Meshing.jl](https://discourse.julialang.org/t/meaning-of-tetedgecrnrs-and-tettri-in-marching-tetrahedra-jl-of-meshing-jl/3903)

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**Author:** [@mohamed82008](https://discourse.julialang.org/u/mohamed82008)\
**Replies:** 0\
**Last updated:** [May 24, 2017, 10:04am UTC](https://discourse.julialang.org/t/meaning-of-tetedgecrnrs-and-tettri-in-marching-tetrahedra-jl-of-meshing-jl/3903 "2017-05-24T10:04:10Z")

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The following is part of the source code of marching\_tetrahedra.jl in the Meshing.jl module. The tetEdgeCrnrs and tetTri fields of the VoxelIndices immutable don’t really make sense to me, so I would appreciate the help…

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## [Can VTK.jl load and save vtk and pvd files?](https://discourse.julialang.org/t/can-vtk-jl-load-and-save-vtk-and-pvd-files/3901)

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**Author:** [@mohamed82008](https://discourse.julialang.org/u/mohamed82008)\
**Replies:** 4\
**Last updated:** [May 24, 2017, 9:31am UTC](https://discourse.julialang.org/t/can-vtk-jl-load-and-save-vtk-and-pvd-files/3901 "2017-05-24T09:31:14Z")

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I am trying to figure out the mesh importing and exporting capabilities of Julia. I came across VTK.jl but but it was hardly documented, so I wonder, is it possible to use VTK.jl to load and save vtk or pvd file formats? …

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## [Visualizing a 3D Vectorfield](https://discourse.julialang.org/t/visualizing-a-3d-vectorfield/3852)

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**Author:** [@steinhagelvoll](https://discourse.julialang.org/u/steinhagelvoll)\
**Replies:** 7\
**Last updated:** [May 24, 2017, 6:38am UTC](https://discourse.julialang.org/t/visualizing-a-3d-vectorfield/3852 "2017-05-24T06:38:56Z")

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I am trying to visualize a 3D Vectorfield like this: Is there any Julia library capable of creating plots like these?

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## [Special functions , associated Legendre type 3](https://discourse.julialang.org/t/special-functions-associated-legendre-type-3/2163)

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**Author:** [@elaine](https://discourse.julialang.org/u/elaine)\
**Replies:** 15\
**Last updated:** [May 23, 2017, 12:51am UTC](https://discourse.julialang.org/t/special-functions-associated-legendre-type-3/2163 "2017-05-23T00:51:33Z")

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I have some special functions. I would like to deposit them into someone’s existing / new projects. An example: function mylegenp3(n,m,z)# n,m integers , z \> 1,associated Legendre v=(z\*z - big(1.))^(-m\*big(1)/2) …

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## [Pipe to CSV.Source](https://discourse.julialang.org/t/pipe-to-csv-source/3764)

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**Author:** [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Replies:** 4\
**Last updated:** [May 22, 2017, 10:23pm UTC](https://discourse.julialang.org/t/pipe-to-csv-source/3764 "2017-05-22T22:23:17Z")

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I have a gzip-compressed CSV file in which uses commas for the decimal mark. I can uncompress and then use tr on the command line, but I would prefer doing that using a pipe from Julia. I tried using CSV using DataStrea…

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## [A Suggestion to Integrate GLVisualize and Paraview](https://discourse.julialang.org/t/a-suggestion-to-integrate-glvisualize-and-paraview/3844)

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**Author:** [@mohamed82008](https://discourse.julialang.org/u/mohamed82008)\
**Replies:** 4\
**Last updated:** [May 22, 2017, 6:27pm UTC](https://discourse.julialang.org/t/a-suggestion-to-integrate-glvisualize-and-paraview/3844 "2017-05-22T18:27:04Z")

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I am a fan of Paraview and a student of GLVisualize. In my usecase, I am trying to make and visualize mesh node data, including scalar and vector fields defined over those nodes. Paraview does an excellent job at that u…

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## [Generating strongly correlated data for numerical experiments](https://discourse.julialang.org/t/generating-strongly-correlated-data-for-numerical-experiments/3842)

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**Author:** [@varun7rs](https://discourse.julialang.org/u/varun7rs)\
**Replies:** 4\
**Last updated:** [May 22, 2017, 11:10am UTC](https://discourse.julialang.org/t/generating-strongly-correlated-data-for-numerical-experiments/3842 "2017-05-22T11:10:38Z")

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Since real-life traffic traces are not readily available, for my simulations, I generate traffic traces as follows: trace = \[\] nom = sample(collect(0.5:0.2,0.9), WeightVec(\[0.3,0.4,0.3\])) for i=1:100 push!(trace, nom …

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## [JuMP variable definition](https://discourse.julialang.org/t/jump-variable-definition/920)

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**Author:** [@ashefa](https://discourse.julialang.org/u/ashefa)\
**Replies:** 12\
**Last updated:** [May 20, 2017, 4:13pm UTC](https://discourse.julialang.org/t/jump-variable-definition/920 "2017-05-20T16:13:22Z")

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how i can defined different bounds or fixed values to elements of a vector variable?

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## [Syntax Error while running MPC with Ipopt](https://discourse.julialang.org/t/syntax-error-while-running-mpc-with-ipopt/3817)

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**Author:** [@Angshuman\_Goswami](https://discourse.julialang.org/u/Angshuman_Goswami)\
**Replies:** 1\
**Last updated:** [May 20, 2017, 12:26pm UTC](https://discourse.julialang.org/t/syntax-error-while-running-mpc-with-ipopt/3817 "2017-05-20T12:26:26Z")

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I am working with the simulator with a 3DOF-bicycle model. I am having a problem when I use the dynamic model in the MPC. When I am using the kinematic model, it works. I have uploaded the files here. (https://github.co…

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## [Sample random matrix](https://discourse.julialang.org/t/sample-random-matrix/3789)

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**Author:** [@jacobcvt12](https://discourse.julialang.org/u/jacobcvt12)\
**Replies:** 3\
**Last updated:** [May 18, 2017, 3:29pm UTC](https://discourse.julialang.org/t/sample-random-matrix/3789 "2017-05-18T15:29:18Z")

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Hi all, I’m trying to sample a random matrix, where each element is independent. For example, if I have a matrix of means M = \[1. 10.; 100. 1000.\] and I want to generate data, where each element is sampled as an expon…

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## [Specifying the coefficients for a 2D polynomial in ApproxFun.jl](https://discourse.julialang.org/t/specifying-the-coefficients-for-a-2d-polynomial-in-approxfun-jl/3782)

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**Author:** [@JackDevine](https://discourse.julialang.org/u/JackDevine)\
**Replies:** 4\
**Last updated:** [May 18, 2017, 8:13pm UTC](https://discourse.julialang.org/t/specifying-the-coefficients-for-a-2d-polynomial-in-approxfun-jl/3782 "2017-05-18T20:13:50Z")

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I am trying to understand how ApproxFun.jl constructs 2D functions from their coefficients. In 1D, it all makes sense, for example: julia\> using ApproxFun julia\> f = Fun(Interval(-1, 1), \[1,2,3\]) Fun(Chebyshev(【-1.0,1.…

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## [Violin plot interpolates too much](https://discourse.julialang.org/t/violin-plot-interpolates-too-much/3784)

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**Author:** [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Replies:** 9\
**Last updated:** [May 18, 2017, 1:03pm UTC](https://discourse.julialang.org/t/violin-plot-interpolates-too-much/3784 "2017-05-18T13:03:04Z")

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I am trying to draw a violin plot of forest structure (distribution of volumes by diameter class). The problem is that violin plot try to interpolate “too much” and draws too many waves: using DataFrames, Plots, StatPl…

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## ["multivariate curve resolution"... a NMF using ALS?](https://discourse.julialang.org/t/multivariate-curve-resolution-a-nmf-using-als/3274)

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**Author:** [@charlesll](https://discourse.julialang.org/u/charlesll)\
**Replies:** 1\
**Last updated:** [May 18, 2017, 7:02am UTC](https://discourse.julialang.org/t/multivariate-curve-resolution-a-nmf-using-als/3274 "2017-05-18T07:02:06Z")

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Dear all, I am using Julia and the JuliaStats ecosystem together with SciKit-learn (thanks PyCall) to perform component analysis and blind-source separation in various Raman and also XAFS spectra of glasses with varying…

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## [Asymmetric violin plot (different right/left series)](https://discourse.julialang.org/t/asymmetric-violin-plot-different-right-left-series/3770)

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**Author:** [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Replies:** 2\
**Last updated:** [May 17, 2017, 9:42pm UTC](https://discourse.julialang.org/t/asymmetric-violin-plot-different-right-left-series/3770 "2017-05-17T21:42:19Z")

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Hello, I am trying to obtain a violin plot with different series on the right and on the left. I have tried this code plying from the example in the doc, but I am unable to specify that one series should be on the left …

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## [Speed up this code game](https://discourse.julialang.org/t/speed-up-this-code-game/3666)

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**Author:** [@Glen](https://discourse.julialang.org/u/Glen)\
**Replies:** 13\
**Last updated:** [May 17, 2017, 3:37am UTC](https://discourse.julialang.org/t/speed-up-this-code-game/3666 "2017-05-17T03:37:45Z")

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Hi, Brag points are up for grabs again. How can this code be made faster? using BenchmarkTools using Base.Test struct Point{X,Y} x::X y::Y end function integral\_squared(v::Vector{Point{X,Y}}) where {X,Y} …

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## [Custom DataFrame column sort order](https://discourse.julialang.org/t/custom-dataframe-column-sort-order/3716)

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**Author:** [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Replies:** 5\
**Last updated:** [May 16, 2017, 1:41pm UTC](https://discourse.julialang.org/t/custom-dataframe-column-sort-order/3716 "2017-05-16T13:41:22Z")

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Is it possible to sort a DataFrame column based on custom sort order, e.g. df = DataFrame(col1= \['a','b','c'\], col2 = \[1,2,3\]) sort!(df, col1=custom\_order('a','c','b'))

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## [Thinking through distance matrix calculation](https://discourse.julialang.org/t/thinking-through-distance-matrix-calculation/3725)

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**Author:** [@randyzwitch](https://discourse.julialang.org/u/randyzwitch)\
**Replies:** 5\
**Last updated:** [May 16, 2017, 1:35pm UTC](https://discourse.julialang.org/t/thinking-through-distance-matrix-calculation/3725 "2017-05-16T13:35:27Z")

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I got a workstation with 2 P5000 cards in it and I want to check out CUDAnative.jl (or other options people can suggest). I understand why GPUs can produce faster results for brute force calculations, but this is my firs…

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## [Gadfly - plot with several graphs, suitable for publications](https://discourse.julialang.org/t/gadfly-plot-with-several-graphs-suitable-for-publications/3718)

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**Author:** [@lanaperisa](https://discourse.julialang.org/u/lanaperisa)\
**Replies:** 2\
**Last updated:** [May 15, 2017, 5:58pm UTC](https://discourse.julialang.org/t/gadfly-plot-with-several-graphs-suitable-for-publications/3718 "2017-05-15T17:58:54Z")

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I’ve lost quite a lot of time to figure our how to include different line styles on graphs with different colors, so it is suitable for black&white publications. After several switching from package to package I’ve decid…

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## [A question on extrapolation with Interpolations.jl](https://discourse.julialang.org/t/a-question-on-extrapolation-with-interpolations-jl/3669)

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**Author:** [@JackDevine](https://discourse.julialang.org/u/JackDevine)\
**Replies:** 15\
**Last updated:** [May 15, 2017, 9:20am UTC](https://discourse.julialang.org/t/a-question-on-extrapolation-with-interpolations-jl/3669 "2017-05-15T09:20:37Z")

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Say that I make an array that I want to do extrapolation on: using Interpolations a = \[1,2,3,4\] a = interpolate!(a, BSpline(Linear()), OnGrid()) a = extrapolate(a, 3) Then a\[0\] = 3 and likewise for any index outside of…

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## [Significand of IEEE float as an integer](https://discourse.julialang.org/t/significand-of-ieee-float-as-an-integer/3698)

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**Author:** [@fengyang.wang](https://discourse.julialang.org/u/fengyang.wang)\
**Replies:** 2\
**Last updated:** [May 14, 2017, 8:25pm UTC](https://discourse.julialang.org/t/significand-of-ieee-float-as-an-integer/3698 "2017-05-14T20:25:25Z")

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I want a function like frexp, but that returns an integer (of the same size of the floating point) and an exponent. Currently I have tried the following implementation: julia\> inexp(x::T) where T \<: Base.Math.IEEEFloat …

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## [Julia and web app security](https://discourse.julialang.org/t/julia-and-web-app-security/3621)

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**Author:** [@datnamer](https://discourse.julialang.org/u/datnamer)\
**Replies:** 6\
**Last updated:** [May 13, 2017, 8:01am UTC](https://discourse.julialang.org/t/julia-and-web-app-security/3621 "2017-05-13T08:01:39Z")

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Django has had lots of time invested in its security, but I want to go with an all Julia stack. Is it a bad idea to select Julia (specifically genie.jl) for a web application if security is a potential concern? can one o…

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## [Iterate delimited file as NamedTuples](https://discourse.julialang.org/t/iterate-delimited-file-as-namedtuples/3616)

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**Author:** [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Replies:** 6\
**Last updated:** [May 13, 2017, 6:16am UTC](https://discourse.julialang.org/t/iterate-delimited-file-as-namedtuples/3616 "2017-05-13T06:16:34Z")

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I have (gzip compressed) files that have ;-delimited rows. I would like to iterate over the rows of each file so that in the body of the iteration, I would have a NamedTuple of the raw fields, ie unparsed. This is becaus…

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## [Gurobi SOC Constraint](https://discourse.julialang.org/t/gurobi-soc-constraint/3683)

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**Author:** [@ahassansan](https://discourse.julialang.org/u/ahassansan)\
**Replies:** 12\
**Last updated:** [May 13, 2017, 1:43am UTC](https://discourse.julialang.org/t/gurobi-soc-constraint/3683 "2017-05-13T01:43:32Z")

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I am having issues using Gurobi Solver for my SOC formulation. Following are my constraints: I am getting an error ERROR: LoadError: MethodError: no method matching NonlinearModel(::Gurobi.GurobiSolver) The mathematic…

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## [Help with DataStreams toy problem](https://discourse.julialang.org/t/help-with-datastreams-toy-problem/3675)

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**Author:** [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)\
**Replies:** 10\
**Last updated:** [May 12, 2017, 7:45pm UTC](https://discourse.julialang.org/t/help-with-datastreams-toy-problem/3675 "2017-05-12T19:45:50Z")

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I am trying to learn my way around DataStreams. I thought I would implement a simple source which just gives random values (code below). Yet when I write a CSV from it, the file only contains the header. What am I doing …

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## [ANN: Genie.jl updates: new website, new workflow and API docs](https://discourse.julialang.org/t/ann-genie-jl-updates-new-website-new-workflow-and-api-docs/3676)

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**Author:** [@essenciary](https://discourse.julialang.org/u/essenciary)\
**Replies:** 0\
**Last updated:** [May 12, 2017, 4:54pm UTC](https://discourse.julialang.org/t/ann-genie-jl-updates-new-website-new-workflow-and-api-docs/3676 "2017-05-12T16:54:07Z")

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I’m super happy to announce some major Genie milestones: 1/ Genie now has a website at http://genieframework.com – it has getting started tips as well as info about Genie and links to API docs, repos and other useful re…

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## [Julia 0.6 Unicode Parsing Problem](https://discourse.julialang.org/t/julia-0-6-unicode-parsing-problem/3649)

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**Author:** [@Daneel](https://discourse.julialang.org/u/Daneel)\
**Replies:** 4\
**Last updated:** [May 12, 2017, 7:55am UTC](https://discourse.julialang.org/t/julia-0-6-unicode-parsing-problem/3649 "2017-05-12T07:55:24Z")

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Julia 0.6.0-rc1.0 can’t properly load a Unicode character in a settings file I have, specifically “³” (U+00b3). Julia doesn’t have a problem if it’s a UTF-8 Unicode file but the settings files we have are generated in IS…

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