# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=294

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**Page:** 295

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## [Which low latency library for drawing polygon on image + extracting values?](https://discourse.julialang.org/t/which-low-latency-library-for-drawing-polygon-on-image-extracting-values/78291)

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**Author:** [@Klaas\_Pauly](https://discourse.julialang.org/u/Klaas_Pauly)\
**Replies:** 0\
**Last updated:** [March 22, 2022, 5:11pm UTC](https://discourse.julialang.org/t/which-low-latency-library-for-drawing-polygon-on-image-extracting-values/78291 "2022-03-22T17:11:16Z")

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I’m looking for a solution similar to R’s clickpoly from spatstat.geom (for those familiar with it). The goal is to let a user draw a polygon on a displayed image (greyscale or heatmap) by clicking the desired vertex poi…

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## [Options for large-scale dense linear algebra](https://discourse.julialang.org/t/options-for-large-scale-dense-linear-algebra/78227)

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**Author:** [@wcwitt](https://discourse.julialang.org/u/wcwitt)\
**Replies:** 1\
**Last updated:** [March 22, 2022, 10:18am UTC](https://discourse.julialang.org/t/options-for-large-scale-dense-linear-algebra/78227 "2022-03-22T10:18:06Z")

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My team is trying to identify options for dense-matrix distributed linear algebra on ~100s-1000s of CPU cores spread over multiple nodes. We are hoping for at least QR and Cholesky factorization, as well as linear equati…

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## [Find which constrains are violated in an IPOPT JuMP model](https://discourse.julialang.org/t/find-which-constrains-are-violated-in-an-ipopt-jump-model/78228)

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**Author:** [@this\_josh](https://discourse.julialang.org/u/this_josh)\
**Replies:** 2\
**Last updated:** [March 22, 2022, 8:35am UTC](https://discourse.julialang.org/t/find-which-constrains-are-violated-in-an-ipopt-jump-model/78228 "2022-03-22T08:35:31Z")

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I have a model I’m trying to optimise which is returning “LOCALLY\_INFEASIBLE”. When using a linear solver like Gurobi at this point I’d compute conflicts, I appreciate this isn’t possible when working with a non-linear I…

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## [Fill missing kwarg in vcat function when cols = :union](https://discourse.julialang.org/t/fill-missing-kwarg-in-vcat-function-when-cols-union/78214)

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**Author:** [@rocco\_sprmnt21](https://discourse.julialang.org/u/rocco_sprmnt21)\
**Replies:** 3\
**Last updated:** [March 22, 2022, 8:39am UTC](https://discourse.julialang.org/t/fill-missing-kwarg-in-vcat-function-when-cols-union/78214 "2022-03-22T08:39:45Z")

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I am submitting to you a question which I believe to be of a general nature (along with other issues arising from the case), derived from a particular case on which I was working. I find myself in the need to make trans…

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## [MethodError: no method matching ^(::QuadExpr, ::Float64)](https://discourse.julialang.org/t/methoderror-no-method-matching-quadexpr-float64/78247)

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**Author:** [@Eric.O](https://discourse.julialang.org/u/Eric.O)\
**Replies:** 4\
**Last updated:** [March 22, 2022, 3:37am UTC](https://discourse.julialang.org/t/methoderror-no-method-matching-quadexpr-float64/78247 "2022-03-22T03:37:42Z")

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I am trying to run this code in Julia but I keep getting this error MethodError: no method matching ^(::QuadExpr, ::Float64) below is my code: I will be grateful if someone can help me correct this error. Thanks in adv…

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## [RNN Sentiment analysis example with Flux: how to use batch ? which value for the inner state?](https://discourse.julialang.org/t/rnn-sentiment-analysis-example-with-flux-how-to-use-batch-which-value-for-the-inner-state/78224)

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**Author:** [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Replies:** 0\
**Last updated:** [March 21, 2022, 4:05pm UTC](https://discourse.julialang.org/t/rnn-sentiment-analysis-example-with-flux-how-to-use-batch-which-value-for-the-inner-state/78224 "2022-03-21T16:05:42Z")

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Hello, the code belows model a RNN for sentiment analysis over Amazon reviews. My main problem is that I don’t know how to batch a recursive cell when the sequence (i.e. the review text) has variable length. In the \[do…

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## [Best Nonlinear Optimizer for a Continuous Convex Problem](https://discourse.julialang.org/t/best-nonlinear-optimizer-for-a-continuous-convex-problem/77771)

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**Author:** [@jmcastro2109](https://discourse.julialang.org/u/jmcastro2109)\
**Replies:** 44\
**Last updated:** [March 21, 2022, 2:38pm UTC](https://discourse.julialang.org/t/best-nonlinear-optimizer-for-a-continuous-convex-problem/77771 "2022-03-21T14:38:51Z")

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Hi, I have a simple problem in which I want to \\max\_{x \\in \\mathbb{R}^{N}} f(x) \\text{s.t}\\hspace{5pt}x \\geq 0 where f(x) is continuous and globally concave. Which is the best solver for nonlinear, globally conca…

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## [Call for Plots examples](https://discourse.julialang.org/t/call-for-plots-examples/78206)

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**Author:** [@JohnnyChen94](https://discourse.julialang.org/u/JohnnyChen94)\
**Replies:** 0\
**Last updated:** [March 21, 2022, 11:48am UTC](https://discourse.julialang.org/t/call-for-plots-examples/78206 "2022-03-21T11:48:15Z")

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I’m not an experienced Plots user; every time when I use Plots I try to find an example that looks useful and try to modify it. With the help of @BeastyBlacksmith we’ve finally set up the demo gallery using DemoCards.jl,…

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## [\[Makie, AlgebraOfGraphics\] Multiline title pushed content out of frame](https://discourse.julialang.org/t/makie-algebraofgraphics-multiline-title-pushed-content-out-of-frame/77865)

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**Author:** [@TheLateKronos](https://discourse.julialang.org/u/TheLateKronos)\
**Replies:** 1\
**Last updated:** [March 21, 2022, 9:11am UTC](https://discourse.julialang.org/t/makie-algebraofgraphics-multiline-title-pushed-content-out-of-frame/77865 "2022-03-21T09:11:00Z")

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I want a plot with a multiline title. I am plotting via AlgebraOfGraphics.jl. The problem is that the title (set by current\_axis().title = ) pushes content out of frame when it becomes multiline. I also tried adding Labe…

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## [Cvodes error](https://discourse.julialang.org/t/cvodes-error/78175)

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**Author:** [@Yinmin\_Liu](https://discourse.julialang.org/u/Yinmin_Liu)\
**Replies:** 1\
**Last updated:** [March 21, 2022, 12:28am UTC](https://discourse.julialang.org/t/cvodes-error/78175 "2022-03-21T00:28:31Z")

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Hi, I am trying to solve a very large stiff system with the CVODE\_BDF() solver. When I apply the Jacobian-free solver by setting linear\_solver =: GMRES, it magically solved my problem with about 20 sec, which I believe …

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## [Right way to define a constraint](https://discourse.julialang.org/t/right-way-to-define-a-constraint/78116)

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**Author:** [@Popeye](https://discourse.julialang.org/u/Popeye)\
**Replies:** 2\
**Last updated:** [March 20, 2022, 11:54pm UTC](https://discourse.julialang.org/t/right-way-to-define-a-constraint/78116 "2022-03-20T23:54:36Z")

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I am having difficulty in defining a constraint efficiently that is based on a matrix of decision variables. A MWE is given below but as you will see it creates a number of intermediate expressions, so it is not the best…

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## [Continual learning in xgboost](https://discourse.julialang.org/t/continual-learning-in-xgboost/78163)

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**Author:** [@roh\_codeur](https://discourse.julialang.org/u/roh_codeur)\
**Replies:** 0\
**Last updated:** [March 20, 2022, 2:17pm UTC](https://discourse.julialang.org/t/continual-learning-in-xgboost/78163 "2022-03-20T14:17:53Z")

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Hi I am planning on using continual learning in XGboost. In python, it would work as below: https://xgboost.readthedocs.io/en/latest/python/python\_api.html#xgboost.XGBRegressor.fit https://stackoverflow.com/questions/…

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## [Nonparametric functions for time-varying parameters in ODE models?](https://discourse.julialang.org/t/nonparametric-functions-for-time-varying-parameters-in-ode-models/78137)

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**Author:** [@sdwfrost](https://discourse.julialang.org/u/sdwfrost)\
**Replies:** 1\
**Last updated:** [March 20, 2022, 11:33am UTC](https://discourse.julialang.org/t/nonparametric-functions-for-time-varying-parameters-in-ode-models/78137 "2022-03-20T11:33:47Z")

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Dear All, I’m interested in having an ODE model where the parameters change over time specified by some nonparametric function e.g. splines, or at least some sort of basis function over time, etc. so I can get a flexibl…

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## [ModelingToolkit: Some questions on usage & best practices](https://discourse.julialang.org/t/modelingtoolkit-some-questions-on-usage-best-practices/77426)

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**Author:** [@RobertS](https://discourse.julialang.org/u/RobertS)\
**Replies:** 5\
**Last updated:** [March 20, 2022, 8:49am UTC](https://discourse.julialang.org/t/modelingtoolkit-some-questions-on-usage-best-practices/77426 "2022-03-20T08:49:55Z")

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Based on an earlier discussion here on discourse formulated a physical system in Modeling toolkit. The system consists of a discretized 1D PDE, ODEs and an algebraic equation. The physical nature of the system is further…

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## [ModelingToolkit: Building a DAEProblem and solving it with IDA with KLU & Jacobian usage](https://discourse.julialang.org/t/modelingtoolkit-building-a-daeproblem-and-solving-it-with-ida-with-klu-jacobian-usage/77814)

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**Author:** [@RobertS](https://discourse.julialang.org/u/RobertS)\
**Replies:** 3\
**Last updated:** [March 20, 2022, 8:41am UTC](https://discourse.julialang.org/t/modelingtoolkit-building-a-daeproblem-and-solving-it-with-ida-with-klu-jacobian-usage/77814 "2022-03-20T08:41:13Z")

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I have coded an MTK system that I build a DAEProblem from. I am now trying to find out how to solve that problem using Sundials IDA with KLU as linear solver. As far as I know, this requires that the Jacobian matrix is g…

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## [Is there a way to write a coordinate plane on top of an image?](https://discourse.julialang.org/t/is-there-a-way-to-write-a-coordinate-plane-on-top-of-an-image/77796)

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**Author:** [@matic\_lauko](https://discourse.julialang.org/u/matic_lauko)\
**Replies:** 8\
**Last updated:** [March 20, 2022, 7:03am UTC](https://discourse.julialang.org/t/is-there-a-way-to-write-a-coordinate-plane-on-top-of-an-image/77796 "2022-03-20T07:03:57Z")

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Is there a way to write a coordinate plane on an image? And be able to get some coordinates of some points. The second part is not necessary. Thank you.

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## [Isolation Forests?](https://discourse.julialang.org/t/isolation-forests/77859)

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**Author:** [@compleat](https://discourse.julialang.org/u/compleat)\
**Replies:** 5\
**Last updated:** [March 19, 2022, 8:51pm UTC](https://discourse.julialang.org/t/isolation-forests/77859 "2022-03-19T20:51:30Z")

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Has anyone found or implemented a routine for Isolation Forests in Julia? Thanks in advance.

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## [How to have multiple processes use the same GPU?](https://discourse.julialang.org/t/how-to-have-multiple-processes-use-the-same-gpu/78103)

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**Author:** [@jmair](https://discourse.julialang.org/u/jmair)\
**Replies:** 2\
**Last updated:** [March 18, 2022, 8:05pm UTC](https://discourse.julialang.org/t/how-to-have-multiple-processes-use-the-same-gpu/78103 "2022-03-18T20:05:55Z")

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Hi, I have a problem where I have an “embarrassingly” parallel task which uses the GPU. This task would be able to run fine on a GPU with ~3GB of memory, but I have a 3090ti with 24GB of RAM. I want to parallelise this …

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## [BSON error when loading Flux model](https://discourse.julialang.org/t/bson-error-when-loading-flux-model/78085)

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**Author:** [@luciano-drozda](https://discourse.julialang.org/u/luciano-drozda)\
**Replies:** 7\
**Last updated:** [March 19, 2022, 4:53pm UTC](https://discourse.julialang.org/t/bson-error-when-loading-flux-model/78085 "2022-03-19T16:53:42Z")

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The command m = BSON.load("model.bson", @\_\_MODULE\_\_)\[:m\] is throwing ERROR: MethodError: Cannot \`convert\` an object of type CuContext to an object of type CuPtr{Nothing} Closest candidates are: convert(::Type{CuPtr{…

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## [Flux LayerNorm slower than pytorch?](https://discourse.julialang.org/t/flux-layernorm-slower-than-pytorch/78084)

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**Author:** [@gpucce](https://discourse.julialang.org/u/gpucce)\
**Replies:** 10\
**Last updated:** [March 18, 2022, 10:46pm UTC](https://discourse.julialang.org/t/flux-layernorm-slower-than-pytorch/78084 "2022-03-18T22:46:38Z")

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I closed a similar topic I opened about one hour ago by mistake, here I try again with clearer example, the issue is that the same LayerNorm layer in pytorch and Flux has large difference in performance and I don’t know …

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## [Order of legend entries in AlgebraOfGraphics](https://discourse.julialang.org/t/order-of-legend-entries-in-algebraofgraphics/77753)

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**Author:** [@Jakob](https://discourse.julialang.org/u/Jakob)\
**Replies:** 11\
**Last updated:** [March 18, 2022, 6:41pm UTC](https://discourse.julialang.org/t/order-of-legend-entries-in-algebraofgraphics/77753 "2022-03-18T18:41:43Z")

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Hi everyone, does anyone know of a way to specify the order of the legend entries created by AlgebraOfGraphics? In the following, the labels get reordered alphabetically but i’d like them to stay in the original order: …

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## [Spherical Cap in Julia](https://discourse.julialang.org/t/spherical-cap-in-julia/78027)

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**Author:** [@OliveiraIgor](https://discourse.julialang.org/u/OliveiraIgor)\
**Replies:** 3\
**Last updated:** [March 18, 2022, 4:31pm UTC](https://discourse.julialang.org/t/spherical-cap-in-julia/78027 "2022-03-18T16:31:53Z")

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I need to use a set of points from a spherical cap to apply KPCA in Julia, but I don’t know how to create these caps, which idea should I use for this application?

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## [Are there Julia packages for RNA/DNA/protein structure prediction?](https://discourse.julialang.org/t/are-there-julia-packages-for-rna-dna-protein-structure-prediction/78060)

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**Author:** [@BetaQ](https://discourse.julialang.org/u/BetaQ)\
**Replies:** 7\
**Last updated:** [March 18, 2022, 5:39pm UTC](https://discourse.julialang.org/t/are-there-julia-packages-for-rna-dna-protein-structure-prediction/78060 "2022-03-18T17:39:25Z")

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I am doing research about RNA and proteins. Therefore, I am looking for a method to simulate the secondary or 3D structure. I have used some methods based on other programming language constructs. But those methods are n…

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## [Gillespie simulations: don't deepcopy(JumpProblem)](https://discourse.julialang.org/t/gillespie-simulations-dont-deepcopy-jumpproblem/78073)

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**Author:** [@levasco](https://discourse.julialang.org/u/levasco)\
**Replies:** 9\
**Last updated:** [March 18, 2022, 4:10pm UTC](https://discourse.julialang.org/t/gillespie-simulations-dont-deepcopy-jumpproblem/78073 "2022-03-18T16:10:04Z")

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Example from the docs. It seems that deepcopying a JumpProblem object causes each copy to be solved with the same seed. Is this known? using DifferentialEquations using Catalyst sir\_model = @reaction\_network begin β…

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## [Systems Dynamics in Julia?](https://discourse.julialang.org/t/systems-dynamics-in-julia/73882)

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**Author:** [@rpmuller](https://discourse.julialang.org/u/rpmuller)\
**Replies:** 11\
**Last updated:** [March 18, 2022, 12:41pm UTC](https://discourse.julialang.org/t/systems-dynamics-in-julia/73882 "2022-03-18T12:41:34Z")

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Spending a lot of time on the winter break reading Donella Meadows’ books (Thinking in Systems, Limits to Growth and sequels). Seems like a natural extension of the DiffEq.jl framework. Has anyone started anything along …

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## [Turing.jl and StaticArrays](https://discourse.julialang.org/t/turing-jl-and-staticarrays/77768)

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**Author:** [@Marco\_Lombardi](https://discourse.julialang.org/u/Marco_Lombardi)\
**Replies:** 1\
**Last updated:** [March 18, 2022, 8:59am UTC](https://discourse.julialang.org/t/turing-jl-and-staticarrays/77768 "2022-03-18T08:59:34Z")

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I am having troubles using Turing.jl with a custom distribution using a StaticArray as internal parameter. Consider the simple code below, where the TestDistribution is effectively a simple multivariate normal 3D distrib…

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## [Apparent inconsistent plotting of histograms in Gadfly](https://discourse.julialang.org/t/apparent-inconsistent-plotting-of-histograms-in-gadfly/77953)

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**Author:** [@evan-wehi](https://discourse.julialang.org/u/evan-wehi)\
**Replies:** 3\
**Last updated:** [March 18, 2022, 2:27am UTC](https://discourse.julialang.org/t/apparent-inconsistent-plotting-of-histograms-in-gadfly/77953 "2022-03-18T02:27:39Z")

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Why is the histogram for the WildType normalised data differently when plotted with other data compared to being plotted alone? This plot command plot(df\[df.genotype .== "WildType", :\], x=:level, Geom.histogram(bincoun…

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## [MathOptInterface: How to create a 2-dimensional variable?](https://discourse.julialang.org/t/mathoptinterface-how-to-create-a-2-dimensional-variable/78039)

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**Author:** [@Timothy\_Yu](https://discourse.julialang.org/u/Timothy_Yu)\
**Replies:** 4\
**Last updated:** [March 18, 2022, 2:07am UTC](https://discourse.julialang.org/t/mathoptinterface-how-to-create-a-2-dimensional-variable/78039 "2022-03-18T02:07:33Z")

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I am new to MOI and am looking for something equivalent to JuMP’s @variable(model, x\[P,M\] \>=0).

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## [Second order 2D differentiation DiffEqOperators.jl](https://discourse.julialang.org/t/second-order-2d-differentiation-diffeqoperators-jl/77239)

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**Author:** [@Siempie](https://discourse.julialang.org/u/Siempie)\
**Replies:** 5\
**Last updated:** [March 17, 2022, 11:42pm UTC](https://discourse.julialang.org/t/second-order-2d-differentiation-diffeqoperators-jl/77239 "2022-03-17T23:42:18Z")

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Hello i am trying to calculate the laplacian of a 2D array for the use in diffeq.jl And expand later to 3D hopefully. I am currently implementing it using DiffEqOperators.jl with centereddifference() and neuman0BC() H…

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## [JuMP or Convex: stuck with very specific constraint, not sure if possible as originally intended](https://discourse.julialang.org/t/jump-or-convex-stuck-with-very-specific-constraint-not-sure-if-possible-as-originally-intended/77989)

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**Author:** [@johnabs](https://discourse.julialang.org/u/johnabs)\
**Replies:** 5\
**Last updated:** [March 17, 2022, 4:38pm UTC](https://discourse.julialang.org/t/jump-or-convex-stuck-with-very-specific-constraint-not-sure-if-possible-as-originally-intended/77989 "2022-03-17T16:38:55Z")

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Hi everyone, Let me start with a “visual” of my issue: imagine a binary matrix with some constraints on how the rows and columns can “interact” with each other. In my case, I need a constraint within each row that guara…

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