# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=120

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**Page:** 121

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## [DataFrames Adding Rows of Different Number of Cols](https://discourse.julialang.org/t/dataframes-adding-rows-of-different-number-of-cols/112725)

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**Author:** [@chelseas](https://discourse.julialang.org/u/chelseas)\
**Replies:** 2\
**Last updated:** [April 9, 2024, 1:28pm UTC](https://discourse.julialang.org/t/dataframes-adding-rows-of-different-number-of-cols/112725 "2024-04-09T13:28:36Z")

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I’m interested in adding a row to a dataframe where the row may have a different number of columns / different columns than the existing data frame. I get the following error when I push a dictionary: push!(mydatafra…

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## [SumOfSquares on a variety, inspecting the multipliers](https://discourse.julialang.org/t/sumofsquares-on-a-variety-inspecting-the-multipliers/112574)

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**Author:** [@votroto](https://discourse.julialang.org/u/votroto)\
**Replies:** 6\
**Last updated:** [April 9, 2024, 12:54pm UTC](https://discourse.julialang.org/t/sumofsquares-on-a-variety-inspecting-the-multipliers/112574 "2024-04-09T12:54:30Z")

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Is it possible with SumOfSquares to inspect the multipliers of the polynomial decomposition? Let’s say I have a poly p and I wish to maximize it over a variety F defined by polys f\_i,..,f\_n. I assume internally the cons…

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## [Arrows on Axis in Makie](https://discourse.julialang.org/t/arrows-on-axis-in-makie/79015)

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**Author:** [@kfrb](https://discourse.julialang.org/u/kfrb)\
**Replies:** 7\
**Last updated:** [April 9, 2024, 12:33pm UTC](https://discourse.julialang.org/t/arrows-on-axis-in-makie/79015 "2024-04-09T12:33:59Z")

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First, I love Makie and am currently switching to it as my daily plotting library! I often need arrow tips on the axis ends. Unfortunately, I could not find anything about it in the docs, so I used the following workaro…

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## [GPU Genetic Algorithm](https://discourse.julialang.org/t/gpu-genetic-algorithm/112700)

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**Author:** [@fender9723](https://discourse.julialang.org/u/fender9723)\
**Replies:** 12\
**Last updated:** [April 9, 2024, 10:07am UTC](https://discourse.julialang.org/t/gpu-genetic-algorithm/112700 "2024-04-09T10:07:33Z")

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Hello everyone! I’m fairly new to Julia and am attempting to enhance the performance of my code. I have a straightforward optimization problem involving finding the maximum of a function. The variables in my problem ar…

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## [Rowgap!() not working properly](https://discourse.julialang.org/t/rowgap-not-working-properly/112682)

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**Author:** [@brotmesmer](https://discourse.julialang.org/u/brotmesmer)\
**Replies:** 2\
**Last updated:** [April 9, 2024, 8:36am UTC](https://discourse.julialang.org/t/rowgap-not-working-properly/112682 "2024-04-09T08:36:21Z")

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Hi all, when trying to layout a plot similar to the the example in the Makie layout tutorial i ran into a problem using the rowgap!() command: MethodError: objects of type Int64 are not callable colgap!() works flawle…

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## [SoPlex from JuMP ? (available through SCIP ?)](https://discourse.julialang.org/t/soplex-from-jump-available-through-scip/112117)

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**Author:** [@JonT](https://discourse.julialang.org/u/JonT)\
**Replies:** 3\
**Last updated:** [April 9, 2024, 7:08am UTC](https://discourse.julialang.org/t/soplex-from-jump-available-through-scip/112117 "2024-04-09T07:08:09Z")

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I have a problem for which there is a recursive branch and bound algorithm using exact arithmetic in a simplex solver (QSopt\_ex). It is very slow even for small problems, and I was hoping to explore a heuristic to improv…

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## [Have an strange error creating optimization subproblems on Julia](https://discourse.julialang.org/t/have-an-strange-error-creating-optimization-subproblems-on-julia/112692)

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**Author:** [@benjamin.nunez](https://discourse.julialang.org/u/benjamin.nunez)\
**Replies:** 5\
**Last updated:** [April 9, 2024, 5:27am UTC](https://discourse.julialang.org/t/have-an-strange-error-creating-optimization-subproblems-on-julia/112692 "2024-04-09T05:27:53Z")

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Hello! I’m experiencing a rather strange problem in Julia when creating optimization subproblems. Basically I have a function called “build\_subproblem(s)” which depends on a scenario “s” and formulates an optimization p…

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## [Save plot as a JPEG file](https://discourse.julialang.org/t/save-plot-as-a-jpeg-file/112684)

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**Author:** [@eweiss](https://discourse.julialang.org/u/eweiss)\
**Replies:** 1\
**Last updated:** [April 8, 2024, 3:57pm UTC](https://discourse.julialang.org/t/save-plot-as-a-jpeg-file/112684 "2024-04-08T15:57:02Z")

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Is there any way to save a plot (from Plots but I’m open to something else) as a jpeg? I’m creating several hundred simple line graphs as pngs, but I’d like to speed loading on the web by jusing a jpeg.None of the Julia …

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## [Improving performance of calculating Symbolics Jacobians?](https://discourse.julialang.org/t/improving-performance-of-calculating-symbolics-jacobians/112681)

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**Author:** [@Undermine28](https://discourse.julialang.org/u/Undermine28)\
**Replies:** 7\
**Last updated:** [April 8, 2024, 1:47pm UTC](https://discourse.julialang.org/t/improving-performance-of-calculating-symbolics-jacobians/112681 "2024-04-08T13:47:41Z")

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I am trying to calculate the Observation Matrix of a non-linear system. To do this I need to find more and more difficult Lie derivatives. This requires calculating recursive Jacobians. Very quickly, Symbolics seems to …

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## [PEtab with MethodOfLines](https://discourse.julialang.org/t/petab-with-methodoflines/112647)

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**Author:** [@kkakosim](https://discourse.julialang.org/u/kkakosim)\
**Replies:** 4\
**Last updated:** [April 8, 2024, 4:23am UTC](https://discourse.julialang.org/t/petab-with-methodoflines/112647 "2024-04-08T04:23:47Z")

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Any examples utilizing PEtab.jl for parameter fitting with MethodOfLines.jl? If not, then could an ODESystem be (re)constructed from an ODEProblem or a PDESystem?

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## [DAE mass matrix formulation fails but implicit formulation works](https://discourse.julialang.org/t/dae-mass-matrix-formulation-fails-but-implicit-formulation-works/104940)

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**Author:** [@aaliqureshi](https://discourse.julialang.org/u/aaliqureshi)\
**Replies:** 19\
**Last updated:** [April 7, 2024, 3:32pm UTC](https://discourse.julialang.org/t/dae-mass-matrix-formulation-fails-but-implicit-formulation-works/104940 "2024-04-07T15:32:27Z")

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This question links to my previous post. I am simulating a DAE system and noticed that the mass matrix based formulation fails but the implicit DAE formulation works fine. Is this a bug or is there something else goi…

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## [ContinuousDataDrivenProblem stuck if no time derivatives provided](https://discourse.julialang.org/t/continuousdatadrivenproblem-stuck-if-no-time-derivatives-provided/105758)

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**Author:** [@Maxime-Fantino](https://discourse.julialang.org/u/Maxime-Fantino)\
**Replies:** 1\
**Last updated:** [April 7, 2024, 1:44pm UTC](https://discourse.julialang.org/t/continuousdatadrivenproblem-stuck-if-no-time-derivatives-provided/105758 "2024-04-07T13:44:55Z")

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Hello, I am trying to do inference on particle dynamics with data coming from a simulator, using the DataDrivenDiffEq package. Similarly to what is done in the documentation (Automatically Discover Missing Physics by E…

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## [Model discovery using Sparse Regression on UDE model](https://discourse.julialang.org/t/model-discovery-using-sparse-regression-on-ude-model/106698)

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**Author:** [@gsh19](https://discourse.julialang.org/u/gsh19)\
**Replies:** 1\
**Last updated:** [April 7, 2024, 1:44pm UTC](https://discourse.julialang.org/t/model-discovery-using-sparse-regression-on-ude-model/106698 "2024-04-07T13:44:05Z")

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Hi everyone, I am working on modeling the unknown physics of a non-autonomous system. The system has 5 states and 2 control inputs. The dynamics of states 1 to 3 are known precisely but those of states 4 and 5 are unkno…

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## [Tips for Estimating Non-linear Latent SDE](https://discourse.julialang.org/t/tips-for-estimating-non-linear-latent-sde/104326)

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**Author:** [@dleather](https://discourse.julialang.org/u/dleather)\
**Replies:** 1\
**Last updated:** [April 7, 2024, 1:42pm UTC](https://discourse.julialang.org/t/tips-for-estimating-non-linear-latent-sde/104326 "2024-04-07T13:42:20Z")

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I was hoping to use Turing.jl alongside DifferentialEquations.jl to estimate a partially observable SDE via quasi-likelihood methods. Being new to continuous-time models, I was hoping to get some suggestions on the most …

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## [Callbacks after integration step but before integration function](https://discourse.julialang.org/t/callbacks-after-integration-step-but-before-integration-function/103676)

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**Author:** [@jondavis847](https://discourse.julialang.org/u/jondavis847)\
**Replies:** 3\
**Last updated:** [April 7, 2024, 1:38pm UTC](https://discourse.julialang.org/t/callbacks-after-integration-step-but-before-integration-function/103676 "2024-04-07T13:38:51Z")

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As an alternative to DAE definition or SavingCallbacks, I’m using a FunctionCallingCallback with DifferentialEquations.jl to solve algebraic states for an ODE. The callback would need to occur after the integration times…

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## [Help modeling advection-diffusion equation with ModelingToolkit.jl](https://discourse.julialang.org/t/help-modeling-advection-diffusion-equation-with-modelingtoolkit-jl/105028)

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**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\
**Replies:** 27\
**Last updated:** [April 7, 2024, 1:36pm UTC](https://discourse.julialang.org/t/help-modeling-advection-diffusion-equation-with-modelingtoolkit-jl/105028 "2024-04-07T13:36:10Z")

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First time trying to use ModelingToolkit.jl in a project. Appreciate if someone can help with a simple 1D example of advection-diffusion: R \\frac{\\partial c}{\\partial t} = D \\frac{\\partial^2 c}{\\partial x^2} - v \\frac{\\…

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## [NeuralPDE debuging: is it posible to get the loss of a point in the domain?](https://discourse.julialang.org/t/neuralpde-debuging-is-it-posible-to-get-the-loss-of-a-point-in-the-domain/105427)

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**Author:** [@Knud\_Sorensen](https://discourse.julialang.org/u/Knud_Sorensen)\
**Replies:** 2\
**Last updated:** [April 7, 2024, 1:32pm UTC](https://discourse.julialang.org/t/neuralpde-debuging-is-it-posible-to-get-the-loss-of-a-point-in-the-domain/105427 "2024-04-07T13:32:27Z")

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Hi. I am solving some differential equations with NeuralPDE and the solutions don’t look like expected. So, I really want to plot the loss at every point in the domain to see what is going on. Is there any way to get t…

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## [Example for integro-differential equation with NeuralPDE does not run](https://discourse.julialang.org/t/example-for-integro-differential-equation-with-neuralpde-does-not-run/104603)

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**Author:** [@TommasoStentella](https://discourse.julialang.org/u/TommasoStentella)\
**Replies:** 2\
**Last updated:** [April 7, 2024, 1:24pm UTC](https://discourse.julialang.org/t/example-for-integro-differential-equation-with-neuralpde-does-not-run/104603 "2024-04-07T13:24:15Z")

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I am trying to use NeuralPDE for solving an integro-differential equation with the aim of later embedding a neural network in it. To begin with, I tried the example I found in the documentation, but it gives me an error: …

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## [Lipschitz continuity -- Neural ODEs](https://discourse.julialang.org/t/lipschitz-continuity-neural-odes/108463)

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**Author:** [@RahulManavalan](https://discourse.julialang.org/u/RahulManavalan)\
**Replies:** 2\
**Last updated:** [April 7, 2024, 12:13pm UTC](https://discourse.julialang.org/t/lipschitz-continuity-neural-odes/108463 "2024-04-07T12:13:28Z")

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Here’s a open ended topic that I haven’t seen people mention, explicitly in literature. In order to integrate neural ODEs, there needs to be guarentees regarding the existence of its solutions. And any arbitrary NN appr…

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## [Annotating only a few points with StatsPlots](https://discourse.julialang.org/t/annotating-only-a-few-points-with-statsplots/112635)

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**Author:** [@dlshew19](https://discourse.julialang.org/u/dlshew19)\
**Replies:** 1\
**Last updated:** [April 7, 2024, 9:50am UTC](https://discourse.julialang.org/t/annotating-only-a-few-points-with-statsplots/112635 "2024-04-07T09:50:09Z")

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Basically I’m trying label the a few of the markers with a name column of my dataframe. I have stats on the x and y axis and I want to label the player who’s it is but I don’t want to crowd the plot. This is how the data…

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## [What are \`autodiff\_deferred\` and \`autodiff\_thunk\` for in Enzyme?](https://discourse.julialang.org/t/what-are-autodiff-deferred-and-autodiff-thunk-for-in-enzyme/112065)

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**Author:** [@gdalle](https://discourse.julialang.org/u/gdalle)\
**Replies:** 23\
**Last updated:** [April 7, 2024, 5:37am UTC](https://discourse.julialang.org/t/what-are-autodiff-deferred-and-autodiff-thunk-for-in-enzyme/112065 "2024-04-07T05:37:00Z")

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I think I understand the basic autodiff function (see this post) but it has three variants: autodiff\_deferred autodiff\_thunk (which seems broken on 1.11) autodiff\_deferred\_thunk Is there someone who can explain to me: …

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## [Preconditioner for Sundials IDA solver in DifferentialEquations.jl](https://discourse.julialang.org/t/preconditioner-for-sundials-ida-solver-in-differentialequations-jl/105124)

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**Author:** [@jespfra](https://discourse.julialang.org/u/jespfra)\
**Replies:** 4\
**Last updated:** [April 6, 2024, 10:11pm UTC](https://discourse.julialang.org/t/preconditioner-for-sundials-ida-solver-in-differentialequations-jl/105124 "2024-04-06T22:11:24Z")

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Hello Everyone, In DifferentialEquations.jl, I have not found an example of how to should set a preconditioner for the Sundials IDA solver. I have found examples of how to set it up for ODE systems for the CVODE\_BDF sol…

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## [Discretization problem using MOL](https://discourse.julialang.org/t/discretization-problem-using-mol/105514)

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**Author:** [@Johan\_Ekberg](https://discourse.julialang.org/u/Johan_Ekberg)\
**Replies:** 2\
**Last updated:** [April 6, 2024, 9:50pm UTC](https://discourse.julialang.org/t/discretization-problem-using-mol/105514 "2024-04-06T21:50:00Z")

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Hi im trying to solve a 4th order PDE using the MethodOfLines package but im getting the following error messege when trying to discretize my system in space. Could the problem be caused by the mixed derivative? The PDES…

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## [Inconsistency when solving system of SDE with diagonal noise](https://discourse.julialang.org/t/inconsistency-when-solving-system-of-sde-with-diagonal-noise/111608)

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**Author:** [@matt1](https://discourse.julialang.org/u/matt1)\
**Replies:** 1\
**Last updated:** [April 6, 2024, 9:49pm UTC](https://discourse.julialang.org/t/inconsistency-when-solving-system-of-sde-with-diagonal-noise/111608 "2024-04-06T21:49:05Z")

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Hello, I noticed a strange behaviour of Julia when trying to solve the following system of SDE: \\begin{align} du\_1 &= \\left(\\frac{1}{1+c^2}\\right) \\left( -\\frac{u\_4 - 2u\_3+ u\_4}{2d^2} + (u\_1^2 + u\_3^2)u\_3 - c \\left( -…

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## [Enzyme Reverse Diff rules for complex sqrt](https://discourse.julialang.org/t/enzyme-reverse-diff-rules-for-complex-sqrt/111489)

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**Author:** [@dchang10](https://discourse.julialang.org/u/dchang10)\
**Replies:** 6\
**Last updated:** [April 6, 2024, 4:32pm UTC](https://discourse.julialang.org/t/enzyme-reverse-diff-rules-for-complex-sqrt/111489 "2024-04-06T16:32:36Z")

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I have a function that I’m trying to reverse mode diff through that at some point needs to calculate the square root of a complex number. I have been able to define custom rules for the Forward mode autodiff in the follo…

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## [Memory issues for large computational graph](https://discourse.julialang.org/t/memory-issues-for-large-computational-graph/112606)

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**Author:** [@Arijit\_Bhattacharya](https://discourse.julialang.org/u/Arijit_Bhattacharya)\
**Replies:** 3\
**Last updated:** [April 6, 2024, 3:11pm UTC](https://discourse.julialang.org/t/memory-issues-for-large-computational-graph/112606 "2024-04-06T15:11:56Z")

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I’m working on developing a differentiable CFD solver incorporating the immersed boundary method for solving the Navier-Stokes equations. I plan on using Enzyme.jl .My goal is to compute gradients of a parametric geometr…

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## [DeepAR in Julia](https://discourse.julialang.org/t/deepar-in-julia/71707)

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**Author:** [@wormholestds9](https://discourse.julialang.org/u/wormholestds9)\
**Replies:** 3\
**Last updated:** [April 6, 2024, 10:53am UTC](https://discourse.julialang.org/t/deepar-in-julia/71707 "2024-04-06T10:53:28Z")

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Does anybody know if there is a Julia package for DeepAR from Amazon? Do I just have to make do by calling its Python package?

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## [Understanding variable orders in \`\`MOI.VariableIndex\`\` in JuMP](https://discourse.julialang.org/t/understanding-variable-orders-in-moi-variableindex-in-jump/112594)

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**Author:** [@Maybe](https://discourse.julialang.org/u/Maybe)\
**Replies:** 1\
**Last updated:** [April 6, 2024, 5:37am UTC](https://discourse.julialang.org/t/understanding-variable-orders-in-moi-variableindex-in-jump/112594 "2024-04-06T05:37:06Z")

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I am trying to understand the variable orders in MOI.VariableIndex. For example, in the following model m = Model() @variable(m, 0 \<= x\[i=1:2\] \<= 2 ) @variable(m, z) @variable(m, 0 \<= y\[i=1:3\] \<= 1) The outcome of …

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## [Turing.jl Bayesian SDE tutorial doesn't sample posterior chain](https://discourse.julialang.org/t/turing-jl-bayesian-sde-tutorial-doesnt-sample-posterior-chain/112592)

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**Author:** [@anprasad](https://discourse.julialang.org/u/anprasad)\
**Replies:** 0\
**Last updated:** [April 6, 2024, 1:02am UTC](https://discourse.julialang.org/t/turing-jl-bayesian-sde-tutorial-doesnt-sample-posterior-chain/112592 "2024-04-06T01:02:32Z")

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The parameter inference of the SDE in the Turing.jl tutorial doesn’t sample the posterior. Is this an error?

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## [Set\_normalized\_coefficient in JuMP.jl is slow](https://discourse.julialang.org/t/set-normalized-coefficient-in-jump-jl-is-slow/112533)

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**Author:** [@PaterPen](https://discourse.julialang.org/u/PaterPen)\
**Replies:** 6\
**Last updated:** [April 5, 2024, 9:29pm UTC](https://discourse.julialang.org/t/set-normalized-coefficient-in-jump-jl-is-slow/112533 "2024-04-05T21:29:01Z")

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Hi, I wonder why set\_normalized\_coefficient takes about as long as the actual optimization in my MWE: using JuMP, HiGHS function create\_solver(solver, l, C, d, lb) model = direct\_model(optimizer\_with\_attributes(sol…

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