# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?page=508

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**Page:** 509

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## [Getting the optimal solution](https://discourse.julialang.org/t/getting-the-optimal-solution/21167)

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**Author:** [@Rajat\_Sanyal](https://discourse.julialang.org/u/Rajat_Sanyal)\
**Replies:** 2\
**Last updated:** [February 25, 2019, 2:22pm UTC](https://discourse.julialang.org/t/getting-the-optimal-solution/21167 "2019-02-25T14:22:13Z")

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Let us consider the following optimization problem: using JuMP, Ipopt function Opti\_model(A,b) m = Model(with\_optimizer(Ipopt.Optimizer)) @variable(m,x\[1:5\],lower\_bound=0,upper\_bound=1) @objective(m,Max,sum(…

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## [SVD of Matrix w/ updated columns](https://discourse.julialang.org/t/svd-of-matrix-w-updated-columns/21048)

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**Author:** [@DrPapa](https://discourse.julialang.org/u/DrPapa)\
**Replies:** 7\
**Last updated:** [February 22, 2019, 5:26pm UTC](https://discourse.julialang.org/t/svd-of-matrix-w-updated-columns/21048 "2019-02-22T17:26:20Z")

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I have a M\\times N matrix A where N\>\>M. I need to compute the SVD of sub-matrices using a sliding window over the columns, i.e. svd(A\[:,1:k\]), svd(A\[:,2:k+1\]), svd(A\[:,3:k+2\])… Does anybody know of an efficient way to u…

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## [Flux custom loss function](https://discourse.julialang.org/t/flux-custom-loss-function/21127)

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**Author:** [@jstrube](https://discourse.julialang.org/u/jstrube)\
**Replies:** 3\
**Last updated:** [February 24, 2019, 9:45pm UTC](https://discourse.julialang.org/t/flux-custom-loss-function/21127 "2019-02-24T21:45:11Z")

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I’m trying to run a straightforward regression problem through Flux. I’ve modified the loss function from the example, from a simple mse to something like a chi-square. The problem has to do with the calibration of a cal…

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## [Rank-revealing QR/SVD Decompositions](https://discourse.julialang.org/t/rank-revealing-qr-svd-decompositions/21155)

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**Author:** [@Hans\_W\_Borchers](https://discourse.julialang.org/u/Hans_W_Borchers)\
**Replies:** 0\
**Last updated:** [February 24, 2019, 8:27pm UTC](https://discourse.julialang.org/t/rank-revealing-qr-svd-decompositions/21155 "2019-02-24T20:27:23Z")

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Are there implementations of rank-revealing QR/SVD decompositions, resp. QR and SVD updating / downdating mechanisms in any Julia package? See for instance: \[1\] Li and Zheng, A Rank-revealing Method with Updating, Down…

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## [VegaLite rescale data plots](https://discourse.julialang.org/t/vegalite-rescale-data-plots/21143)

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**Author:** [@nik.ltin](https://discourse.julialang.org/u/nik.ltin)\
**Replies:** 0\
**Last updated:** [February 24, 2019, 1:32pm UTC](https://discourse.julialang.org/t/vegalite-rescale-data-plots/21143 "2019-02-24T13:32:54Z")

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Hello all, I’m using VegaLite for bar plots with the @vlplot(:bar...) command. I’m looking at a dataset that I’d like to rescale to go from 1 to 100. I tried adding in the command julia\> y={:df1, scale={domain=\[0,100\]…

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## [VegaLite rescale plots domain](https://discourse.julialang.org/t/vegalite-rescale-plots-domain/21120)

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**Author:** [@nik.ltin](https://discourse.julialang.org/u/nik.ltin)\
**Replies:** 0\
**Last updated:** [February 23, 2019, 7:44pm UTC](https://discourse.julialang.org/t/vegalite-rescale-plots-domain/21120 "2019-02-23T19:44:23Z")

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Hello all, I’m using VegaLite for bar plots with the @vlplot(:bar...) command. I’m looking at a dataset that I’d like to rescale to go from 1 to 100. I tried adding in the command y={:df1, scale={domain=\[0,100\], nice=fal…

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## [Storing mouse click event coordinates in PyPlot window](https://discourse.julialang.org/t/storing-mouse-click-event-coordinates-in-pyplot-window/21117)

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**Author:** [@Carsten](https://discourse.julialang.org/u/Carsten)\
**Replies:** 1\
**Last updated:** [February 23, 2019, 9:01pm UTC](https://discourse.julialang.org/t/storing-mouse-click-event-coordinates-in-pyplot-window/21117 "2019-02-23T21:01:58Z")

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I want to get access to the cursor positions within a PyPlot window and store all clicked values into arrays. I was able to print out the x,y values but I failed to store them into arrays. The code first I used is: fu…

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## [Name styles of variables, parameters, sets, etc...](https://discourse.julialang.org/t/name-styles-of-variables-parameters-sets-etc/21089)

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**Author:** [@haokuny](https://discourse.julialang.org/u/haokuny)\
**Replies:** 1\
**Last updated:** [February 24, 2019, 12:30am UTC](https://discourse.julialang.org/t/name-styles-of-variables-parameters-sets-etc/21089 "2019-02-24T00:30:55Z")

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When building a JuMP model, one thing I feel very important is to distinguish between variables and parameters in each equation. It’s important because, for example, the term “var. \* par.” is linear but the term “var. \* …

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## [Help with my MINLP](https://discourse.julialang.org/t/help-with-my-minlp/19927)

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**Author:** [@muriloasouza](https://discourse.julialang.org/u/muriloasouza)\
**Replies:** 8\
**Last updated:** [February 23, 2019, 6:59pm UTC](https://discourse.julialang.org/t/help-with-my-minlp/19927 "2019-02-23T18:59:52Z")

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Hello, sorry for this long post and problem… but if any help is trully appreciated. I need help with my MINLP, since the results i’m getting is not what i was expecting… This is an electrical engineering problem, where …

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## [Sum dimensions of matrix](https://discourse.julialang.org/t/sum-dimensions-of-matrix/21098)

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**Author:** [@nik.ltin](https://discourse.julialang.org/u/nik.ltin)\
**Replies:** 11\
**Last updated:** [February 23, 2019, 2:25pm UTC](https://discourse.julialang.org/t/sum-dimensions-of-matrix/21098 "2019-02-23T14:25:20Z")

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Hi there, A bit new to Julia so this might be a very basic question: I have a file with a 3 dimensional array (x,y,z), and I’d like to sum certain values from the z dimension to later on pull from and graph. For example…

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## [Make changes of the new model effecting the old one](https://discourse.julialang.org/t/make-changes-of-the-new-model-effecting-the-old-one/21092)

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**Author:** [@haokuny](https://discourse.julialang.org/u/haokuny)\
**Replies:** 2\
**Last updated:** [February 23, 2019, 6:17am UTC](https://discourse.julialang.org/t/make-changes-of-the-new-model-effecting-the-old-one/21092 "2019-02-23T06:17:09Z")

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Let’s say I have built a model called mymodel and I want to make some extension, meaning to add some new variables and constraints, but I want to do it to my new model. So I mymodelnew = mymodel. Then the problem is, wh…

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## [Distributed nested in Pmap](https://discourse.julialang.org/t/distributed-nested-in-pmap/21081)

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**Author:** [@Alessio\_Bellisomi](https://discourse.julialang.org/u/Alessio_Bellisomi)\
**Replies:** 2\
**Last updated:** [February 22, 2019, 5:54pm UTC](https://discourse.julialang.org/t/distributed-nested-in-pmap/21081 "2019-02-22T17:54:59Z")

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Hello, I am fairly new to Julia, I am trying to understand a little better how the workload is distributed, so I prepared this little script to help me out. An external pmap splits the work between different processes,…

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## [UpwindOperator from DiffEqOperators.jl](https://discourse.julialang.org/t/upwindoperator-from-diffeqoperators-jl/21053)

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**Author:** [@boutor2](https://discourse.julialang.org/u/boutor2)\
**Replies:** 2\
**Last updated:** [February 22, 2019, 8:38am UTC](https://discourse.julialang.org/t/upwindoperator-from-diffeqoperators-jl/21053 "2019-02-22T08:38:36Z")

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I have been playing around with DifferentialEquations.jl, mainly for solving reaction diffusion PDE’s. I now wish to add an advection term to my model. For this purpose I discovered DiffEqOperators.jl. UpwindOperator sou…

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## [Initializing Sparse Matrices with CuArrays.jl](https://discourse.julialang.org/t/initializing-sparse-matrices-with-cuarrays-jl/21062)

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**Author:** [@carlomontec](https://discourse.julialang.org/u/carlomontec)\
**Replies:** 4\
**Last updated:** [February 22, 2019, 7:05am UTC](https://discourse.julialang.org/t/initializing-sparse-matrices-with-cuarrays-jl/21062 "2019-02-22T07:05:41Z")

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Hello, total newbie with GPU computing here. I have seen that is possible to use sparse matrices with CuArrays.jl, but I have not found a way to initialize them. I tried to with the example described at https://github.…

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## [Use Symplectic Integrator for ODE for time reversability constraint](https://discourse.julialang.org/t/use-symplectic-integrator-for-ode-for-time-reversability-constraint/20955)

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**Author:** [@mleprovost](https://discourse.julialang.org/u/mleprovost)\
**Replies:** 6\
**Last updated:** [February 21, 2019, 8:39pm UTC](https://discourse.julialang.org/t/use-symplectic-integrator-for-ode-for-time-reversability-constraint/20955 "2019-02-21T20:39:59Z")

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Hi everyone, I would like to use Symplectic Integrators such as VelocityVerlet or VerletLeapfrog from DifferentialEquations.jl to ensure the time-reversibility of the equation of motion. Nonetheless, my problem can no…

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## [About the optimization problem choice in JuMP v0.19](https://discourse.julialang.org/t/about-the-optimization-problem-choice-in-jump-v0-19/21018)

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**Author:** [@ErwanPiR](https://discourse.julialang.org/u/ErwanPiR)\
**Replies:** 8\
**Last updated:** [February 21, 2019, 2:20pm UTC](https://discourse.julialang.org/t/about-the-optimization-problem-choice-in-jump-v0-19/21018 "2019-02-21T14:20:29Z")

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I hope this isn’t a dumb question… With the precedent version of JuMP, to define the kind of optimization problem (LP, MIP,…), the syntax was Model(solver=GLPKSolverMIP(args…)) or Model(solver=GLPKSolverLP()) I …

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## [Package for genome graphics?](https://discourse.julialang.org/t/package-for-genome-graphics/20550)

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**Author:** [@aalexandersson](https://discourse.julialang.org/u/aalexandersson)\
**Replies:** 11\
**Last updated:** [February 21, 2019, 1:27am UTC](https://discourse.julialang.org/t/package-for-genome-graphics/20550 "2019-02-21T01:27:14Z")

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Are there any graphing capabilities in Julia 1.x specifically for genomics (“genome graphs”), for example a genome viewer? Ben Ward illustrated the Julia package GenomeBrowsers in his presentation at JuliaCon 2018. It h…

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## [Confidence Interval for certain Contrast and model residual](https://discourse.julialang.org/t/confidence-interval-for-certain-contrast-and-model-residual/20339)

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**Author:** [@PharmCat](https://discourse.julialang.org/u/PharmCat)\
**Replies:** 13\
**Last updated:** [February 20, 2019, 6:13pm UTC](https://discourse.julialang.org/t/confidence-interval-for-certain-contrast-and-model-residual/20339 "2019-02-20T18:13:44Z")

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I have a model like this: ols = lm(@formula(LnVar ~ Seq+Per+Trt+Subj), df) I try to get confidence interval for Trt contrast, LSM and model residual. How to obtain it? In R you just do confint(lmobj, c("Trt"), level=…

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## [Recommended way to do work stealing in Julia 1.0?](https://discourse.julialang.org/t/recommended-way-to-do-work-stealing-in-julia-1-0/15573)

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**Author:** [@orenbenkiki](https://discourse.julialang.org/u/orenbenkiki)\
**Replies:** 6\
**Last updated:** [February 20, 2019, 1:48pm UTC](https://discourse.julialang.org/t/recommended-way-to-do-work-stealing-in-julia-1-0/15573 "2019-02-20T13:48:02Z")

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I have a Python system which is a mixture of C++ code, pandas/numpy code running on top of BLAS/MKL, and plain Python code binding the whole thing together. “It ain’t a pretty sight”. It can be viewed as a nested tree (…

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## [Keyword arguments in PlotRecipes](https://discourse.julialang.org/t/keyword-arguments-in-plotrecipes/20780)

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**Author:** [@moesphere](https://discourse.julialang.org/u/moesphere)\
**Replies:** 4\
**Last updated:** [February 20, 2019, 7:45am UTC](https://discourse.julialang.org/t/keyword-arguments-in-plotrecipes/20780 "2019-02-20T07:45:52Z")

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Following minimal example: struct PlotType end @recipe function f(::PlotType; title="Title", ylabel="ylabel") x := \[1,2,3\] y := rand(3,5) end The title is plotted fine, I also can change the title when calling …

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## [Error with Ipopt ](https://discourse.julialang.org/t/error-with-ipopt/20989)

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**Author:** [@Y\_Li](https://discourse.julialang.org/u/Y_Li)\
**Replies:** 2\
**Last updated:** [February 20, 2019, 1:32am UTC](https://discourse.julialang.org/t/error-with-ipopt/20989 "2019-02-20T01:32:35Z")

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Hi, I am using JuMP and IPOPT to solve an non-linear optimization, below is my code using JuMP using Ipopt model =Model(solver=IpoptSolver()) @variable(model, x ) @variable(model, y ) @variable(model, z ) #define our ob…

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## [ADAM optimizer error in Flux](https://discourse.julialang.org/t/adam-optimizer-error-in-flux/20947)

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**Author:** [@microlifecc](https://discourse.julialang.org/u/microlifecc)\
**Replies:** 1\
**Last updated:** [February 19, 2019, 6:01pm UTC](https://discourse.julialang.org/t/adam-optimizer-error-in-flux/20947 "2019-02-19T18:01:23Z")

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Hi! I am defining a neural network as: n\_hidden = 20 model = Chain(Dense(n\_inputs, n\_hidden, relu), Dense(n\_hidden, n\_outputs, identity), softmax) L(x,y) = Flux.crossentropy(model(x), y) ps = Flux.params(…

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## [GLM.jl with unknown column names](https://discourse.julialang.org/t/glm-jl-with-unknown-column-names/20692)

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**Author:** [@george](https://discourse.julialang.org/u/george)\
**Replies:** 4\
**Last updated:** [February 19, 2019, 5:47pm UTC](https://discourse.julialang.org/t/glm-jl-with-unknown-column-names/20692 "2019-02-19T17:47:29Z")

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Hello, I’m using Julia for some basic statistical analysis. I’d like to run a simple linear regression on a small dataset using the GLM.jl package. My data looks something like this: │ Row │ stat.id12312.somemetadata …

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## [JuMP: Catch error if solver stops early due to network error or running out of memory ?](https://discourse.julialang.org/t/jump-catch-error-if-solver-stops-early-due-to-network-error-or-running-out-of-memory/20962)

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**Author:** [@Stuart\_Rogers](https://discourse.julialang.org/u/Stuart_Rogers)\
**Replies:** 1\
**Last updated:** [February 19, 2019, 1:32am UTC](https://discourse.julialang.org/t/jump-catch-error-if-solver-stops-early-due-to-network-error-or-running-out-of-memory/20962 "2019-02-19T01:32:55Z")

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I am solving a large MILP by calling Gurobi through JuMP v0.18. Gurobi issues an error, which I believe is due to it running out of RAM. Is it possible for JuMP to catch the error and collect the best known solution?

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## [JuMP v0.19 has been released](https://discourse.julialang.org/t/jump-v0-19-has-been-released/20878)

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**Author:** [@blegat](https://discourse.julialang.org/u/blegat)\
**Replies:** 6\
**Last updated:** [February 18, 2019, 8:22pm UTC](https://discourse.julialang.org/t/jump-v0-19-has-been-released/20878 "2019-02-18T20:22:59Z")

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We are thrilled to announce the release of JuMP v0.19. Work on this release started nearly two years ago at the first JuMP-dev meetup. As introduced in an earlier post and at the second JuMP-dev meetup, JuMP has undergo…

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## [How use SCIP in Windows](https://discourse.julialang.org/t/how-use-scip-in-windows/20929)

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**Author:** [@muriloasouza](https://discourse.julialang.org/u/muriloasouza)\
**Replies:** 3\
**Last updated:** [February 18, 2019, 2:38pm UTC](https://discourse.julialang.org/t/how-use-scip-in-windows/20929 "2019-02-18T14:38:36Z")

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Hello, Can anyone help in how to install SCIP to use it in Windows through Julia 0.6/JuMP? I’ve seen some instructions here: But only for OS X and Linux, so i have no idea what i need to do to use it in Windows. I’…

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## [Median vs 50th Quantile giving different answers](https://discourse.julialang.org/t/median-vs-50th-quantile-giving-different-answers/18414)

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**Author:** [@davidzentlermunro](https://discourse.julialang.org/u/davidzentlermunro)\
**Replies:** 6\
**Last updated:** [February 18, 2019, 1:22pm UTC](https://discourse.julialang.org/t/median-vs-50th-quantile-giving-different-answers/18414 "2019-02-18T13:22:09Z")

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I’m getting different answers for median(v,w::AnalyticWeights) and quantile(v,w::AnalyticWeights,0.5) and not sure why. Any ideas?

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## [How to embed 2D slices of an array in a 3D plot using plot recipes?](https://discourse.julialang.org/t/how-to-embed-2d-slices-of-an-array-in-a-3d-plot-using-plot-recipes/20857)

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**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\
**Replies:** 6\
**Last updated:** [February 18, 2019, 11:49am UTC](https://discourse.julialang.org/t/how-to-embed-2d-slices-of-an-array-in-a-3d-plot-using-plot-recipes/20857 "2019-02-18T11:49:02Z")

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Given a 3D array, I would like to produce the following visualization: The main problem I have is that I don’t know how to embed 2D slices in a 3D plot using plot recipes. Appreciate if you can help, or if you can pr…

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## [SatelliteToolbox.jl now supports IAU-2006/2010 model](https://discourse.julialang.org/t/satellitetoolbox-jl-now-supports-iau-2006-2010-model/20915)

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**Author:** [@Ronis\_BR](https://discourse.julialang.org/u/Ronis_BR)\
**Replies:** 1\
**Last updated:** [February 18, 2019, 6:05am UTC](https://discourse.julialang.org/t/satellitetoolbox-jl-now-supports-iau-2006-2010-model/20915 "2019-02-18T06:05:58Z")

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Hi guys! Just want to announce that with the latest set of commits, SatelliteToolbox.jl now supports the entire IAU-2006/2010 theory (CIO approach). The code is 100% written in Julia without requiring external libraries.…

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## [Vline! alters y-axis labels using Plots with GR](https://discourse.julialang.org/t/vline-alters-y-axis-labels-using-plots-with-gr/20918)

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**Author:** [@colintbowers](https://discourse.julialang.org/u/colintbowers)\
**Replies:** 0\
**Last updated:** [February 18, 2019, 12:43am UTC](https://discourse.julialang.org/t/vline-alters-y-axis-labels-using-plots-with-gr/20918 "2019-02-18T00:43:27Z")

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Hi all, An MWE follows: using Plots dt = \[ today() + Day(10\*n) for n = 1:100 \]; x = randn(100); p = plot(dt, x); savefig(p, "/home/colin/TempPlot/a1.svg"); dtlab = dt\[1:20:100\]; vline!(p, dtlab); savefig(p, "/home/coli…

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