# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=284

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**Page:** 285

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## [Eigenvalue sensitivites using autodiff](https://discourse.julialang.org/t/eigenvalue-sensitivites-using-autodiff/80059)

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**Author:** [@Hofsmo](https://discourse.julialang.org/u/Hofsmo)\
**Replies:** 5\
**Last updated:** [May 2, 2022, 6:30am UTC](https://discourse.julialang.org/t/eigenvalue-sensitivites-using-autodiff/80059 "2022-05-02T06:30:40Z")

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Hi, I am quite new to both julia and autodiff and was wondering if someone can point me in the right direction. I have a dynamic system described using state space representation. I want to calculate the derivative of t…

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## [Defining constraint using JuMP convert String to Expression and Merge Quart Expr and nonlinear Expr](https://discourse.julialang.org/t/defining-constraint-using-jump-convert-string-to-expression-and-merge-quart-expr-and-nonlinear-expr/79967)

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**Author:** [@Deena\_20](https://discourse.julialang.org/u/Deena_20)\
**Replies:** 12\
**Last updated:** [May 2, 2022, 4:43am UTC](https://discourse.julialang.org/t/defining-constraint-using-jump-convert-string-to-expression-and-merge-quart-expr-and-nonlinear-expr/79967 "2022-05-02T04:43:40Z")

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using JuMP,CSV,DataFrames model = Model() @variable(model, x\[1:3\]) @constraint(model, c2, x\[1\] + 2 \* x\[3\] \>= 2) @constraint(model, c4, 4 \<= 2 \* x\[2\] \<= 5) @variable(model,x1\[h in 1:5, i in 1:1, j in 1:2, k in 1:1,p …

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## [Rank1 PSD constraint dual variables](https://discourse.julialang.org/t/rank1-psd-constraint-dual-variables/80348)

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**Author:** [@HWS](https://discourse.julialang.org/u/HWS)\
**Replies:** 8\
**Last updated:** [May 2, 2022, 1:47am UTC](https://discourse.julialang.org/t/rank1-psd-constraint-dual-variables/80348 "2022-05-02T01:47:07Z")

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Hi, I ran the following code in JuMP, @variable(m, x\[1:n\]\>=0) @variable(m, X\[1:n,1:n\], Symmetric) @constraint(m, X\_xx\_cons, \[1 x'; x X\] in PSDCone() ) @objective(m, Min, tr(Q'\*X)+dot(b,x)) optimize!(m) A = dual(X\_xx\_c…

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## [Slow generation of the non-linear expressions](https://discourse.julialang.org/t/slow-generation-of-the-non-linear-expressions/80308)

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**Author:** [@xxxxx](https://discourse.julialang.org/u/xxxxx)\
**Replies:** 4\
**Last updated:** [May 1, 2022, 10:37pm UTC](https://discourse.julialang.org/t/slow-generation-of-the-non-linear-expressions/80308 "2022-05-01T22:37:09Z")

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Hi there, I am new to JuMP and trying to use it for maximum likelihood estimation. I found a very slow step when generating the expressions, and I am not sure how to improve it. Here is the code for a minimum working ex…

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## [Use low precision float type in JuMP](https://discourse.julialang.org/t/use-low-precision-float-type-in-jump/80332)

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**Author:** [@wujinq](https://discourse.julialang.org/u/wujinq)\
**Replies:** 2\
**Last updated:** [May 1, 2022, 9:44pm UTC](https://discourse.julialang.org/t/use-low-precision-float-type-in-jump/80332 "2022-05-01T21:44:44Z")

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I’m working with a large linear SDP problem with JuMP and COSMO and is trying to find whether low float precision contributes to the convergence problem. So I want to change the float type of a smaller problem that works…

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## [Edited video of course “GPU Programming with Julia” at the Swiss National Supercomputing Centre (CSCS) now available](https://discourse.julialang.org/t/edited-video-of-course-gpu-programming-with-julia-at-the-swiss-national-supercomputing-centre-cscs-now-available/80293)

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**Author:** [@samo](https://discourse.julialang.org/u/samo)\
**Replies:** 1\
**Last updated:** [May 1, 2022, 6:46pm UTC](https://discourse.julialang.org/t/edited-video-of-course-gpu-programming-with-julia-at-the-swiss-national-supercomputing-centre-cscs-now-available/80293 "2022-05-01T18:46:29Z")

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Edited video of course “GPU Programming with Julia” at the Swiss National Supercomputing Centre (CSCS) now available!

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## [Edited video of course “GPU Programming with Julia” at the Swiss National Supercomputing Centre (CSCS) now available!](https://discourse.julialang.org/t/edited-video-of-course-gpu-programming-with-julia-at-the-swiss-national-supercomputing-centre-cscs-now-available/80291)

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**Author:** [@samo](https://discourse.julialang.org/u/samo)\
**Replies:** 1\
**Last updated:** [May 1, 2022, 6:44pm UTC](https://discourse.julialang.org/t/edited-video-of-course-gpu-programming-with-julia-at-the-swiss-national-supercomputing-centre-cscs-now-available/80291 "2022-05-01T18:44:42Z")

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Edited video of course “GPU Programming with Julia” at the Swiss National Supercomputing Centre (CSCS) now available

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## [Plot ticks at both top and bottom axis](https://discourse.julialang.org/t/plot-ticks-at-both-top-and-bottom-axis/9550)

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**Author:** [@kaslusimoes](https://discourse.julialang.org/u/kaslusimoes)\
**Replies:** 7\
**Last updated:** [May 1, 2022, 6:13pm UTC](https://discourse.julialang.org/t/plot-ticks-at-both-top-and-bottom-axis/9550 "2022-05-01T18:13:11Z")

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Hi, Is there any way to plot both ‘top’ and ‘bottom’ x axis ticks using Plots.jl? I’m thinking of something like this example from Matplotlib. Thanks!

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## [How to find frequency count for consecutive actions?](https://discourse.julialang.org/t/how-to-find-frequency-count-for-consecutive-actions/78582)

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**Author:** [@xinchin](https://discourse.julialang.org/u/xinchin)\
**Replies:** 10\
**Last updated:** [May 1, 2022, 10:09am UTC](https://discourse.julialang.org/t/how-to-find-frequency-count-for-consecutive-actions/78582 "2022-05-01T10:09:09Z")

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I have a few sizable data sets with rows contains actions of a person in different days. I want to summarize the data as a frequency table that shows the number of times that a specific action followed by another action.…

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## [Cannot change colorbar position](https://discourse.julialang.org/t/cannot-change-colorbar-position/17181)

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**Author:** [@shipengcheng1230](https://discourse.julialang.org/u/shipengcheng1230)\
**Replies:** 6\
**Last updated:** [May 1, 2022, 9:13am UTC](https://discourse.julialang.org/t/cannot-change-colorbar-position/17181 "2022-05-01T09:13:13Z")

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I am trying to change the colorbar position: using Plots # pyplot() plot(rand(10, 2), marker\_z=rand(10), seriestype=:scatter, cb=:top) But the colorbar position won’t move no matter how I specifiy :cb: It is always …

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## [Unable to set\_optimizer\_attribute in BilevelJuMP.jl](https://discourse.julialang.org/t/unable-to-set-optimizer-attribute-in-bileveljump-jl/80240)

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**Author:** [@math\_opt](https://discourse.julialang.org/u/math_opt)\
**Replies:** 6\
**Last updated:** [May 1, 2022, 4:49am UTC](https://discourse.julialang.org/t/unable-to-set-optimizer-attribute-in-bileveljump-jl/80240 "2022-05-01T04:49:18Z")

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I am trying to change the MIPGap parameter for Guorbi: using JuMP, Gurobi, BilevelJuMP model = BilevelModel(Gurobi.Optimizer, mode = BilevelJuMP.SOS1Mode()) set\_optimizer\_attribute(model, "MIPGap", 1e-5) Throws error: …

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## [Split dataframe row into multiple rows](https://discourse.julialang.org/t/split-dataframe-row-into-multiple-rows/80214)

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**Author:** [@Elmo](https://discourse.julialang.org/u/Elmo)\
**Replies:** 8\
**Last updated:** [May 1, 2022, 1:16am UTC](https://discourse.julialang.org/t/split-dataframe-row-into-multiple-rows/80214 "2022-05-01T01:16:57Z")

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Hi all, I am pretty new to using DataFrames (but loving it so far), however, I could not find an obvious way to achieve the following transformation in the docs. Suppose I have a dataframe df below: julia\> using DataF…

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## [Turing: censored regression example](https://discourse.julialang.org/t/turing-censored-regression-example/53837)

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**Author:** [@drbenvincent](https://discourse.julialang.org/u/drbenvincent)\
**Replies:** 9\
**Last updated:** [April 30, 2022, 3:07pm UTC](https://discourse.julialang.org/t/turing-censored-regression-example/53837 "2022-04-30T15:07:28Z")

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Building upon my previous example of truncated regression, I thought I’d do a worked example of censored regression. To clarify, censoring is where observations below a lower bound and/or observations above an upper boun…

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## [Julia CSV.read stopped working](https://discourse.julialang.org/t/julia-csv-read-stopped-working/80247)

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**Author:** [@jjdegruijter](https://discourse.julialang.org/u/jjdegruijter)\
**Replies:** 32\
**Last updated:** [April 30, 2022, 1:19pm UTC](https://discourse.julialang.org/t/julia-csv-read-stopped-working/80247 "2022-04-30T13:19:29Z")

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I’ve been using CSV.read very often, but yesterday it didn’t work anymore. From another thread on this issue I understand that it may be caused by incompatibility of packages, but I haven’t seen a solution yet. I use ju…

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## [Two questions related to using operators in ApproxFun.jl](https://discourse.julialang.org/t/two-questions-related-to-using-operators-in-approxfun-jl/79831)

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**Author:** [@andreasvarga](https://discourse.julialang.org/u/andreasvarga)\
**Replies:** 10\
**Last updated:** [April 30, 2022, 12:32pm UTC](https://discourse.julialang.org/t/two-questions-related-to-using-operators-in-approxfun-jl/79831 "2022-04-30T12:32:01Z")

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I am about to register PeriodicSystems.jl, a new package dedicated to handle linear control systems with periodic time-varying coefficient matrices. For stability analysis, the computation of characteristic exponents of …

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## [Truncated SVD of extended precision matrix](https://discourse.julialang.org/t/truncated-svd-of-extended-precision-matrix/78989)

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**Author:** [@Samuel3008](https://discourse.julialang.org/u/Samuel3008)\
**Replies:** 6\
**Last updated:** [April 30, 2022, 10:03am UTC](https://discourse.julialang.org/t/truncated-svd-of-extended-precision-matrix/78989 "2022-04-30T10:03:21Z")

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Hi, is anybody aware of a way to compute the truncated SVD of an extended precision (128 bit floats in my case) matrix? For the floats, I’d like to use either MultiFloats.jl (seems faster in my testing, so this would be…

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## [Visualizing a dynamic changing graph](https://discourse.julialang.org/t/visualizing-a-dynamic-changing-graph/80255)

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**Author:** [@flobe](https://discourse.julialang.org/u/flobe)\
**Replies:** 2\
**Last updated:** [April 29, 2022, 6:45pm UTC](https://discourse.julialang.org/t/visualizing-a-dynamic-changing-graph/80255 "2022-04-29T18:45:01Z")

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Hi all, I am in the process of implementing a graph using MetaGraphs(Next).jl. The graph dynamically expands over time. Currently, I am using GraphRecipes to visualize the resulting graph at the end of my “time simulat…

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## [Plotting heatmap PlotlyJS, double bar](https://discourse.julialang.org/t/plotting-heatmap-plotlyjs-double-bar/80199)

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**Author:** [@Line](https://discourse.julialang.org/u/Line)\
**Replies:** 3\
**Last updated:** [April 29, 2022, 3:09pm UTC](https://discourse.julialang.org/t/plotting-heatmap-plotlyjs-double-bar/80199 "2022-04-29T15:09:23Z")

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Hi, I am plotting heatmap subplots using PlotlyJS package and get the problem of the bar being double. The input into the heatmap is just values of either 1, 2 or 3. I assume a part of the problem is some plots only take…

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## [Using pmap: Do all workers have to be equally capable?](https://discourse.julialang.org/t/using-pmap-do-all-workers-have-to-be-equally-capable/74122)

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**Author:** [@chelseas](https://discourse.julialang.org/u/chelseas)\
**Replies:** 5\
**Last updated:** [April 29, 2022, 12:18pm UTC](https://discourse.julialang.org/t/using-pmap-do-all-workers-have-to-be-equally-capable/74122 "2022-04-29T12:18:32Z")

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I am using pmap with workers from many computers. Some of those computers have more resources than others ~ does pmap know this? And distribute tasks accordingly? e.g. if I have 10 workers on one machine vs 2 workers on …

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## [Best way to implement distributed read/write with Zarr.jl?](https://discourse.julialang.org/t/best-way-to-implement-distributed-read-write-with-zarr-jl/80243)

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**Author:** [@ConnectedSystems](https://discourse.julialang.org/u/ConnectedSystems)\
**Replies:** 0\
**Last updated:** [April 29, 2022, 7:14am UTC](https://discourse.julialang.org/t/best-way-to-implement-distributed-read-write-with-zarr-jl/80243 "2022-04-29T07:14:21Z")

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Trying out Zarr.jl for comparison with NetCDF.jl I ran into an issue with distributed writes, where workers were silently hanging. I thought I could pass the data store created by zopen() via pmap(), similar to a Share…

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## [How can I get Proj4 to transform multiple locations?](https://discourse.julialang.org/t/how-can-i-get-proj4-to-transform-multiple-locations/80098)

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**Author:** [@chadagreene](https://discourse.julialang.org/u/chadagreene)\
**Replies:** 11\
**Last updated:** [April 29, 2022, 12:32am UTC](https://discourse.julialang.org/t/how-can-i-get-proj4-to-transform-multiple-locations/80098 "2022-04-29T00:32:20Z")

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This is probably more of a Julia question than a Proj4 question, but how can I perform coordinate transformations on multiple locations at once? I’m writing a function that would need to handle the following three cases: …

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## [Replicate Vega-Lite Interactive Index Chart](https://discourse.julialang.org/t/replicate-vega-lite-interactive-index-chart/80231)

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**Author:** [@klwlevy](https://discourse.julialang.org/u/klwlevy)\
**Replies:** 0\
**Last updated:** [April 28, 2022, 10:42pm UTC](https://discourse.julialang.org/t/replicate-vega-lite-interactive-index-chart/80231 "2022-04-28T22:42:41Z")

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Is it possible to replicate this using vegalite.jl? Interactive Index Chart | Vega-Lite

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## [Inconsistent build\_function behavior in Symbolics](https://discourse.julialang.org/t/inconsistent-build-function-behavior-in-symbolics/80230)

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**Author:** [@Elmo](https://discourse.julialang.org/u/Elmo)\
**Replies:** 2\
**Last updated:** [April 28, 2022, 10:08pm UTC](https://discourse.julialang.org/t/inconsistent-build-function-behavior-in-symbolics/80230 "2022-04-28T22:08:04Z")

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Hi, is there a good way to make sure that the output function from build\_function in Symbolics returns output in the same dimensions as the symbolic function used to generate it? In the simple example below, if N = 5, …

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## [Warning: when using both Plots and StatsPlots](https://discourse.julialang.org/t/warning-when-using-both-plots-and-statsplots/50118)

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**Author:** [@Xijiang\_Yu](https://discourse.julialang.org/u/Xijiang_Yu)\
**Replies:** 9\
**Last updated:** [April 28, 2022, 6:35pm UTC](https://discourse.julialang.org/t/warning-when-using-both-plots-and-statsplots/50118 "2022-04-28T18:35:10Z")

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I am working on a package which has both Plots and StatsPlots added. When using density from StatsPlots, even I use StatsPlots.density(blah), I got a warning twice for each density call: ┌ Warning: seriestype density ha…

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## [How to make Geom.errorbar work with Geom.subplot\_grid in Gadfly.jl](https://discourse.julialang.org/t/how-to-make-geom-errorbar-work-with-geom-subplot-grid-in-gadfly-jl/80158)

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**Author:** [@rkmalaiya](https://discourse.julialang.org/u/rkmalaiya)\
**Replies:** 2\
**Last updated:** [April 28, 2022, 5:38pm UTC](https://discourse.julialang.org/t/how-to-make-geom-errorbar-work-with-geom-subplot-grid-in-gadfly-jl/80158 "2022-04-28T17:38:08Z")

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Hello Everyone, I am trying to make bar plot with error bars in a plot grid. But I am getting following error. Please advise what I may be doing wrong. Fake Data v = rand(8) df\_plot = DataFrame( model = repeat(\[“M1…

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## [QML, animations, and asynchronous variable updating](https://discourse.julialang.org/t/qml-animations-and-asynchronous-variable-updating/79995)

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**Author:** [@f.ij](https://discourse.julialang.org/u/f.ij)\
**Replies:** 1\
**Last updated:** [April 28, 2022, 12:45pm UTC](https://discourse.julialang.org/t/qml-animations-and-asynchronous-variable-updating/79995 "2022-04-28T12:45:01Z")

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Hi, I’m trying to build a simple GUI for a metropolis Monte Carlo simulation of a spin ising model. What I want to do, basically is having a while loop in the background running at all times (ideally which can be paused…

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## [How does MixedModels.jl initialize model parameters for optimization?](https://discourse.julialang.org/t/how-does-mixedmodels-jl-initialize-model-parameters-for-optimization/40630)

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**Author:** [@kai](https://discourse.julialang.org/u/kai)\
**Replies:** 1\
**Last updated:** [April 28, 2022, 4:47am UTC](https://discourse.julialang.org/t/how-does-mixedmodels-jl-initialize-model-parameters-for-optimization/40630 "2022-04-28T04:47:25Z")

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Hi, I’m curious about how MixedModels.jl initialize model parameters for optimization. From page 12 of this document This template contains three types of elements: structural zeros (denoted by .), off- diagonal covar…

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## [Is there any glmmTMB package for Julia?](https://discourse.julialang.org/t/is-there-any-glmmtmb-package-for-julia/19868)

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**Author:** [@Juan](https://discourse.julialang.org/u/Juan)\
**Replies:** 15\
**Last updated:** [April 28, 2022, 4:44am UTC](https://discourse.julialang.org/t/is-there-any-glmmtmb-package-for-julia/19868 "2022-04-28T04:44:31Z")

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I’m trying to fit mixed-effect models to large dataset. R’s lme4 is very slow and can’t deal with more than 50000 rows on my computer. The amount of memory seems to increase with the cube of the number of rows. Julia’s…

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## [Help with JuMP extension](https://discourse.julialang.org/t/help-with-jump-extension/79485)

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**Author:** [@math\_opt](https://discourse.julialang.org/u/math_opt)\
**Replies:** 8\
**Last updated:** [April 28, 2022, 2:02am UTC](https://discourse.julialang.org/t/help-with-jump-extension/79485 "2022-04-28T02:02:05Z")

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I am trying to tweak JuMP so that I can specify and query some more specific stuff that I can not currently do with inbuilt JuMP functions and macros. See the example below: First, I want to specify the ‘kind’ of variab…

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## [Querying lower level objective value in BilevelJuMP.jl](https://discourse.julialang.org/t/querying-lower-level-objective-value-in-bileveljump-jl/80084)

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**Author:** [@math\_opt](https://discourse.julialang.org/u/math_opt)\
**Replies:** 3\
**Last updated:** [April 28, 2022, 1:06am UTC](https://discourse.julialang.org/t/querying-lower-level-objective-value-in-bileveljump-jl/80084 "2022-04-28T01:06:38Z")

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Is there an inbuilt function I can use to query the lower level objective value when using BilevelJuMP.jl? For the following example: using JuMP, BilevelJuMP, Gurobi model = BilevelModel(Gurobi.Optimizer, mode = Bilev…

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