# Specific Domains **URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=268 [Latest](https://discourse.julialang.org/latest.md) · [Categories](https://discourse.julialang.org/categories.md) · [Tags](https://discourse.julialang.org/tags.md) **Page:** 269 --- ## [Sparse jacobians of matrix models](https://discourse.julialang.org/t/sparse-jacobians-of-matrix-models/82537)
**Author:** [@gianmariomanca](https://discourse.julialang.org/u/gianmariomanca)\ **Replies:** 37\ **Last updated:** [July 3, 2022, 6:16pm UTC](https://discourse.julialang.org/t/sparse-jacobians-of-matrix-models/82537 "2022-07-03T18:16:47Z")
Hi all, I would like to use sparsity to speed up an optimization problem. I have a NxM matrix of data Z and a model m(A) = A - k\*sum(A, dims=2)\*sum(A,dims=1) where A is a matrix of the same dimensions of Z, sum(A, dims… --- ## [Plotting matrix (heatmap/pcolor/imshow) with log scales](https://discourse.julialang.org/t/plotting-matrix-heatmap-pcolor-imshow-with-log-scales/26685)
**Author:** [@dapz](https://discourse.julialang.org/u/dapz)\ **Replies:** 11\ **Last updated:** [July 3, 2022, 5:32pm UTC](https://discourse.julialang.org/t/plotting-matrix-heatmap-pcolor-imshow-with-log-scales/26685 "2022-07-03T17:32:59Z")
Hi, I’m struggling with plotting a simple matrix with log-scales for x, y and/or color-axis. Consider e.g. a random 5\*5 matrix a, with associated values for x and y axis (these values are always regularly spaced, either… --- ## [Image Processing](https://discourse.julialang.org/t/image-processing/83685)
**Author:** [@Kampuny11](https://discourse.julialang.org/u/Kampuny11)\ **Replies:** 2\ **Last updated:** [July 3, 2022, 2:19pm UTC](https://discourse.julialang.org/t/image-processing/83685 "2022-07-03T14:19:23Z")
Hi! I having the problem to view an 3D Image. Consider the image array as: Image\[:, :, 1\] = 0.0031054 0.00385944 0.00372917 0.000612832 0.0020886 0.000983508 0.000783196 0.000259077 … --- ## [Plug flow with ModelingToolkit?](https://discourse.julialang.org/t/plug-flow-with-modelingtoolkit/82547)
**Author:** [@dodoplus](https://discourse.julialang.org/u/dodoplus)\ **Replies:** 14\ **Last updated:** [July 3, 2022, 1:18pm UTC](https://discourse.julialang.org/t/plug-flow-with-modelingtoolkit/82547 "2022-07-03T13:18:32Z")
Hi, Let’s say I have the following system: A reactor with volume V and two ports (in & out) Two fluid reservoirs, say of oil and water (with different specific densities) A valve selecting which of the reservoirs is c… --- ## [How to draw simulated data from a given turing model given specific parameters](https://discourse.julialang.org/t/how-to-draw-simulated-data-from-a-given-turing-model-given-specific-parameters/83413)
**Author:** [@neuro\_enthusiast](https://discourse.julialang.org/u/neuro_enthusiast)\ **Replies:** 3\ **Last updated:** [July 2, 2022, 3:04pm UTC](https://discourse.julialang.org/t/how-to-draw-simulated-data-from-a-given-turing-model-given-specific-parameters/83413 "2022-07-02T15:04:18Z")
I was wondering how I can simulate data given parameter values using a turing model? Any help would be great! ex. using Turing, Distributions @model function logistic\_regression(x, y, n, σ) intercept ~ Normal(0, σ)… --- ## [Saving and Loading Error BSON.jl](https://discourse.julialang.org/t/saving-and-loading-error-bson-jl/83555)
**Author:** [@ccccc](https://discourse.julialang.org/u/ccccc)\ **Replies:** 4\ **Last updated:** [July 2, 2022, 12:07pm UTC](https://discourse.julialang.org/t/saving-and-loading-error-bson-jl/83555 "2022-07-02T12:07:58Z")
I’m getting an error while saving / loading in BSON: res1\_node = DiffEqFlux.sciml\_train(loss, p, ADAM(0.01), cb=callback, maxiters = 500) using BSON: @save @save "res1\_node" res1\_node when I try to load: using BSON: … --- ## [Speedup over cython/GSL ODE/SDE solvers?](https://discourse.julialang.org/t/speedup-over-cython-gsl-ode-sde-solvers/83490)
**Author:** [@kjohnsen](https://discourse.julialang.org/u/kjohnsen)\ **Replies:** 4\ **Last updated:** [July 1, 2022, 6:28pm UTC](https://discourse.julialang.org/t/speedup-over-cython-gsl-ode-sde-solvers/83490 "2022-07-01T18:28:30Z")
Hello there! I’m somewhat new to Julia. I’m scoping out a spiking neural network/ML project, and I’ve been using Brian 2 simulator a lot in Python. It would consist of training recurrent spiking neural networks to perfor… --- ## [My experience as a Julia and R user](https://discourse.julialang.org/t/my-experience-as-a-julia-and-r-user/83613)
**Author:** [@alfaromartino](https://discourse.julialang.org/u/alfaromartino)\ **Replies:** 8\ **Last updated:** [July 1, 2022, 4:20pm UTC](https://discourse.julialang.org/t/my-experience-as-a-julia-and-r-user/83613 "2022-07-01T16:20:06Z")
Hi! I’m a relatively new user of Julia, and I thought that maybe contributors of DataFrames and Econometrics packages could find my feedback useful. I’ve been primarily using Julia for DataFrames, which is a package I l… --- ## [Metal.jl : Seamless GPU acceleration for Julia based physics using unified processing units?](https://discourse.julialang.org/t/metal-jl-seamless-gpu-acceleration-for-julia-based-physics-using-unified-processing-units/83006)
**Author:** [@LaurentPlagne](https://discourse.julialang.org/u/LaurentPlagne)\ **Replies:** 1\ **Last updated:** [July 1, 2022, 10:38am UTC](https://discourse.julialang.org/t/metal-jl-seamless-gpu-acceleration-for-julia-based-physics-using-unified-processing-units/83006 "2022-07-01T10:38:21Z")
Hi, I found this work about GPU programming with apple silicon machines very interesting : Seamless GPU acceleration for C++ based physics using unified processing units: A case study for elastic wave propagation and PD… --- ## [CairoMakie: any way to save 3D plot in vector format (.svg, .eps)?](https://discourse.julialang.org/t/cairomakie-any-way-to-save-3d-plot-in-vector-format-svg-eps/83122)
**Author:** [@mihai](https://discourse.julialang.org/u/mihai)\ **Replies:** 12\ **Last updated:** [July 1, 2022, 6:08am UTC](https://discourse.julialang.org/t/cairomakie-any-way-to-save-3d-plot-in-vector-format-svg-eps/83122 "2022-07-01T06:08:14Z")
Hi, so far I’ve used CairoMakie for 2D plots (exporting to .svg) while using GLMakie for 3D plots (for interactivity & exporting to .png). Is there any way to use CairoMakie with a 3D plot and export it to .svg? Speed do… --- ## [LinearRegressionKit results correctness](https://discourse.julialang.org/t/linearregressionkit-results-correctness/83579)
**Author:** [@Eric](https://discourse.julialang.org/u/Eric)\ **Replies:** 0\ **Last updated:** [June 30, 2022, 7:52pm UTC](https://discourse.julialang.org/t/linearregressionkit-results-correctness/83579 "2022-06-30T19:52:11Z")
I haven’t posted for a while, but I noticed some discussion on the forum about results correctness, and that got me thinking that maybe I should do more on my little package. Hence I used the tests that everyone seems t… --- ## [Spatial transformer (i.e. GPU-friendly interpolations with gradients) with Flux.jl?](https://discourse.julialang.org/t/spatial-transformer-i-e-gpu-friendly-interpolations-with-gradients-with-flux-jl/70836)
**Author:** [@afishy](https://discourse.julialang.org/u/afishy)\ **Replies:** 7\ **Last updated:** [July 1, 2022, 4:56am UTC](https://discourse.julialang.org/t/spatial-transformer-i-e-gpu-friendly-interpolations-with-gradients-with-flux-jl/70836 "2022-07-01T04:56:17Z")
Originally posted this on the flux-bridged Slack channel, but thought this might be a good place to post. I need a spatial transformer or something equivalent for a project, written so far entirely in Julia. I thought In… --- ## [Remove duplicate legend entries in PlotlyJS combined bar plot](https://discourse.julialang.org/t/remove-duplicate-legend-entries-in-plotlyjs-combined-bar-plot/83502)
**Author:** [@Mario\_Silva](https://discourse.julialang.org/u/Mario_Silva)\ **Replies:** 4\ **Last updated:** [July 1, 2022, 3:00am UTC](https://discourse.julialang.org/t/remove-duplicate-legend-entries-in-plotlyjs-combined-bar-plot/83502 "2022-07-01T03:00:34Z")
Greetings: I am vertically stacking two bar plots from PlotlyJS, which can be interpreted as a historical decomposition of output and the Solow residual over the business cycle into various shocks. The problem is that d… --- ## [Why SDDP.jl can not work together with nonlinear optimizer like juniper](https://discourse.julialang.org/t/why-sddp-jl-can-not-work-together-with-nonlinear-optimizer-like-juniper/83559)
**Author:** [@chenr86](https://discourse.julialang.org/u/chenr86)\ **Replies:** 5\ **Last updated:** [July 1, 2022, 1:56am UTC](https://discourse.julialang.org/t/why-sddp-jl-can-not-work-together-with-nonlinear-optimizer-like-juniper/83559 "2022-07-01T01:56:28Z")
Hello, I’m using JuMP.jl and Juniper.jl to solve a MINLP problem. Now I attempt to consider the uncertainty in some of the constraints by consulting theory guide of SDDP.jl. But I can’t understand how SDDP.jl deal with … --- ## [Unable to plot from the REPL with PyPlot](https://discourse.julialang.org/t/unable-to-plot-from-the-repl-with-pyplot/3112)
**Author:** [@adriano.vilela](https://discourse.julialang.org/u/adriano.vilela)\ **Replies:** 15\ **Last updated:** [June 30, 2022, 4:06pm UTC](https://discourse.julialang.org/t/unable-to-plot-from-the-repl-with-pyplot/3112 "2022-06-30T16:06:57Z")
I recently decided to try Julia 0.6. I installed a Generic Linux binary (nightly build) on my machine. For plotting, I installed PyPlot, using my system’s installation of matplotlib (i.e., not Conda). Plotting works fine… --- ## [Equivalent to Rosetta in Julia](https://discourse.julialang.org/t/equivalent-to-rosetta-in-julia/32168)
**Author:** [@Seanny123](https://discourse.julialang.org/u/Seanny123)\ **Replies:** 4\ **Last updated:** [June 30, 2022, 10:24am UTC](https://discourse.julialang.org/t/equivalent-to-rosetta-in-julia/32168 "2022-06-30T10:24:43Z")
I’ve recently started working at a biotech startup. One of the tools used by these types of companies is the macromolecular modelling tool Rosetta. I don’t totally understand Rosetta’s various capabilities/limitations. T… --- ## [Create an image from matrix](https://discourse.julialang.org/t/create-an-image-from-matrix/83523)
**Author:** [@extremety1989](https://discourse.julialang.org/u/extremety1989)\ **Replies:** 4\ **Last updated:** [June 29, 2022, 4:51pm UTC](https://discourse.julialang.org/t/create-an-image-from-matrix/83523 "2022-06-29T16:51:44Z")
i am using gans to generate an image, it ouputs an array of size (256,256,3,1) “WHCB” how can build an image out of it ? here is an example what i tried, i think i need to remove dim ( channels and batch): function cre… --- ## [Symbolic Arrays have issues with Complex Numbers](https://discourse.julialang.org/t/symbolic-arrays-have-issues-with-complex-numbers/83538)
**Author:** [@Noel\_Araujo](https://discourse.julialang.org/u/Noel_Araujo)\ **Replies:** 1\ **Last updated:** [June 30, 2022, 9:35am UTC](https://discourse.julialang.org/t/symbolic-arrays-have-issues-with-complex-numbers/83538 "2022-06-30T09:35:11Z")
I can’t work with complex numbers multiplying Symbolic Arrays. Here an example: using Symbolics, SpecialFunctions N = 3 @variables r\[1:N, 1:N\], ϕ\[1:N, 1:N\] H = hankelh1.(0, r) P = cos.(ϕ) Q = im.\*cos.(ϕ)# also does n… --- ## [JuMP.write\_to\_file small change to model](https://discourse.julialang.org/t/jump-write-to-file-small-change-to-model/83543)
**Author:** [@Stuart\_Rogers](https://discourse.julialang.org/u/Stuart_Rogers)\ **Replies:** 2\ **Last updated:** [June 30, 2022, 2:34am UTC](https://discourse.julialang.org/t/jump-write-to-file-small-change-to-model/83543 "2022-06-30T02:34:26Z")
I have created a large LP in a JuMP model. I want to write a small variation, e.g. fixing a variable or changing the RHS of a scalar constraint, of the LP to a MPS file using JuMP. write\_to\_file. Once the original LP has… --- ## [Looking for collaborators - implementing SLIDE in julia](https://discourse.julialang.org/t/looking-for-collaborators-implementing-slide-in-julia/83482)
**Author:** [@RickDW](https://discourse.julialang.org/u/RickDW)\ **Replies:** 12\ **Last updated:** [June 29, 2022, 8:39pm UTC](https://discourse.julialang.org/t/looking-for-collaborators-implementing-slide-in-julia/83482 "2022-06-29T20:39:35Z")
Hi everyone, a while back I had a quick discussion with @outlace (over here) about implementing SLIDE. The basic idea is that you don’t need expensive GPUs or other hardware accelerators to train neural nets. All you nee… --- ## [Dataframe Joins in a loop](https://discourse.julialang.org/t/dataframe-joins-in-a-loop/83476)
**Author:** [@Guido](https://discourse.julialang.org/u/Guido)\ **Replies:** 4\ **Last updated:** [June 29, 2022, 7:40pm UTC](https://discourse.julialang.org/t/dataframe-joins-in-a-loop/83476 "2022-06-29T19:40:49Z")
Hi all, I’m learning Julia and I’m stuck trying to merge several dataframes into only one using a loop. For instances, suppose that I have 4 dataframes called A, B, C and D. They have the same column names except for th… --- ## [CUDA.jl - Better GPU but Worse Performance](https://discourse.julialang.org/t/cuda-jl-better-gpu-but-worse-performance/83337)
**Author:** [@moukann](https://discourse.julialang.org/u/moukann)\ **Replies:** 10\ **Last updated:** [June 29, 2022, 6:45pm UTC](https://discourse.julialang.org/t/cuda-jl-better-gpu-but-worse-performance/83337 "2022-06-29T18:45:19Z")
Hello all, I have a question regarding to general usage of CUDA.jl, not a code problem. So we have 2 different computers, both is running on Ubuntu. One of them has Nvidia Quadro P2000 5GB DDR5 160Bit graphics card and… --- ## [Removing singularities from callable functions built from symbolic expressions](https://discourse.julialang.org/t/removing-singularities-from-callable-functions-built-from-symbolic-expressions/83505)
**Author:** [@mrhardman](https://discourse.julialang.org/u/mrhardman)\ **Replies:** 2\ **Last updated:** [June 29, 2022, 5:11pm UTC](https://discourse.julialang.org/t/removing-singularities-from-callable-functions-built-from-symbolic-expressions/83505 "2022-06-29T17:11:09Z")
I have a basic question regarding building functions from symbolic expressions for which I cannot find the answer on the documentation (Symbolic Calculations and Building Callable Functions · Symbolics.jl) Suppose that … --- ## [Generalized affects in MTK - what's a good interface?](https://discourse.julialang.org/t/generalized-affects-in-mtk-whats-a-good-interface/83390)
**Author:** [@dodoplus](https://discourse.julialang.org/u/dodoplus)\ **Replies:** 4\ **Last updated:** [June 29, 2022, 4:57pm UTC](https://discourse.julialang.org/t/generalized-affects-in-mtk-whats-a-good-interface/83390 "2022-06-29T16:57:08Z")
Hi, I’ve recently started a pull request in an attempt to add more generalized affect! support to MTK (and also to support discrete\_events, which is taken on by others) The reason I think this is needed is that in some… --- ## [Store DataFrame or filepath for CSV.read?](https://discourse.julialang.org/t/store-dataframe-or-filepath-for-csv-read/83489)
**Author:** [@RicardoFR](https://discourse.julialang.org/u/RicardoFR)\ **Replies:** 2\ **Last updated:** [June 29, 2022, 4:19pm UTC](https://discourse.julialang.org/t/store-dataframe-or-filepath-for-csv-read/83489 "2022-06-29T16:19:35Z")
Hello all! I’m working with some data using CSV.read and the DataFrame type. The data in its raw form is seldom needed in my code, which got me thinking if I indeed need to store it in my mutable struct in the first pla… --- ## [We need more helpful error messages in ModelingToolkit](https://discourse.julialang.org/t/we-need-more-helpful-error-messages-in-modelingtoolkit/82917)
**Author:** [@dodoplus](https://discourse.julialang.org/u/dodoplus)\ **Replies:** 11\ **Last updated:** [June 29, 2022, 4:13pm UTC](https://discourse.julialang.org/t/we-need-more-helpful-error-messages-in-modelingtoolkit/82917 "2022-06-29T16:13:58Z")
Hi, Trying to solve a model, I’m getting a really unhelpful message: @named x = MixingVolume() sys = structural\_simplify(x) prob = ODAEProblem(sys, \[\], (0, 10.0)) sol = solve(prob, Tsit5()) MethodError: no method … --- ## [Favorite lectures on the Finite Element Method?](https://discourse.julialang.org/t/favorite-lectures-on-the-finite-element-method/83211)
**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\ **Replies:** 4\ **Last updated:** [June 29, 2022, 3:22pm UTC](https://discourse.julialang.org/t/favorite-lectures-on-the-finite-element-method/83211 "2022-06-29T15:22:12Z")
Do you have a favorite set of lectures on the Finite Element Method? Possibly a set of lectures with a heavy list of programming exercises that encourages students to build all the building blocks of a modern software li… --- ## [Add errorbars with dodge in barplot](https://discourse.julialang.org/t/add-errorbars-with-dodge-in-barplot/83504)
**Author:** [@Aesth\_Estheticism](https://discourse.julialang.org/u/Aesth_Estheticism)\ **Replies:** 1\ **Last updated:** [June 29, 2022, 9:02am UTC](https://discourse.julialang.org/t/add-errorbars-with-dodge-in-barplot/83504 "2022-06-29T09:02:40Z")
How to add errorbars with dodge in barplot. --- ## [How do I put a plot in a Blink (electron) desktop application?](https://discourse.julialang.org/t/how-do-i-put-a-plot-in-a-blink-electron-desktop-application/83404)
**Author:** [@davidwallis](https://discourse.julialang.org/u/davidwallis)\ **Replies:** 1\ **Last updated:** [June 29, 2022, 3:09am UTC](https://discourse.julialang.org/t/how-do-i-put-a-plot-in-a-blink-electron-desktop-application/83404 "2022-06-29T03:09:01Z")
Very basic question, but I’ve spent all afternoon looking for an answer. I want to make a cross-platform desktop application and I thought I’d try Blink.jl. I can run the example and create a hello world program appearin… --- ## [Debugging in Ipopt without JuMP](https://discourse.julialang.org/t/debugging-in-ipopt-without-jump/83384)
**Author:** [@Itzahack23](https://discourse.julialang.org/u/Itzahack23)\ **Replies:** 5\ **Last updated:** [June 29, 2022, 1:48am UTC](https://discourse.julialang.org/t/debugging-in-ipopt-without-jump/83384 "2022-06-29T01:48:56Z")
Hi all, I am trying to solve a constrained optimization problem by using Ipopt “without” using JuMP as I want to see how the performance changes by giving the gradient and hessian information. I am referring to the C w… [Previous page](https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=267) [Next page](https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=269)