# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?page=349

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**Page:** 350

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## [Plot 2D histogram of 3D+ multivariate data](https://discourse.julialang.org/t/plot-2d-histogram-of-3d-multivariate-data/65525)

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**Author:** [@thompsonmj](https://discourse.julialang.org/u/thompsonmj)\
**Replies:** 1\
**Last updated:** [July 29, 2021, 10:02pm UTC](https://discourse.julialang.org/t/plot-2d-histogram-of-3d-multivariate-data/65525 "2021-07-29T22:02:09Z")

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To plot a bivariate histogram with as many bins as I like in each dimension, I can use using StatsBase, Plots d1 = randn(10\_000) d2 = randn(10\_000) nbins1 = 25 nbins2 = 10 hist = fit(Histogram, (d1,d2), (range(mini…

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## [How to remove overhead due to nested optimization with Optim package](https://discourse.julialang.org/t/how-to-remove-overhead-due-to-nested-optimization-with-optim-package/65439)

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**Author:** [@Joris\_Pinkse](https://discourse.julialang.org/u/Joris_Pinkse)\
**Replies:** 7\
**Last updated:** [July 29, 2021, 7:36pm UTC](https://discourse.julialang.org/t/how-to-remove-overhead-due-to-nested-optimization-with-optim-package/65439 "2021-07-29T19:36:52Z")

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Consider minimizing f(x, y1, y2) using a nested procedure. In an inner loop y1, y2 are minimized as a function of x and in the outer loop f( x, y1(x), y2(x) ) is minimized where y1(x), y2(x) are the solutions to the inn…

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## [@formula for Lathe.preprocess UndefVarError](https://discourse.julialang.org/t/formula-for-lathe-preprocess-undefvarerror/65504)

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**Author:** [@YummyPampers2](https://discourse.julialang.org/u/YummyPampers2)\
**Replies:** 12\
**Last updated:** [July 29, 2021, 6:11pm UTC](https://discourse.julialang.org/t/formula-for-lathe-preprocess-undefvarerror/65504 "2021-07-29T18:11:48Z")

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Hello Everyone: I am attempting to perform a logistic regression and for some reason the @formula macro, is not reading. using GLM using Lathe: preprocess fm = @formula(Outcome ~ Sesh1 + Shes2 + Sesh3) logit = glm…

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## [Recent errors with WGLMakie on Pluto](https://discourse.julialang.org/t/recent-errors-with-wglmakie-on-pluto/64859)

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**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\
**Replies:** 18\
**Last updated:** [July 29, 2021, 11:54am UTC](https://discourse.julialang.org/t/recent-errors-with-wglmakie-on-pluto/64859 "2021-07-29T11:54:47Z")

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I don’t know what happened but I started getting this warning on a previously working Pluto notebook with WGLMakie plots: ┌ Warning: Waiting for page sessions to load. │ This can happen for the first cel…

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## [Getting started: MIP variables and datastructure](https://discourse.julialang.org/t/getting-started-mip-variables-and-datastructure/63766)

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**Author:** [@Annette\_F](https://discourse.julialang.org/u/Annette_F)\
**Replies:** 11\
**Last updated:** [July 29, 2021, 11:42am UTC](https://discourse.julialang.org/t/getting-started-mip-variables-and-datastructure/63766 "2021-07-29T11:42:33Z")

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Hi all, In short; I’m trying to find if and how I can formulate a MIP on a datastructure. I have a set of orders ( with handling time, start location, end location and each location a timewindow ) And I want to combin…

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## [\`num\_constraints\` to return the total number of constraints](https://discourse.julialang.org/t/num-constraints-to-return-the-total-number-of-constraints/65488)

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**Author:** [@raphaelsaavedra](https://discourse.julialang.org/u/raphaelsaavedra)\
**Replies:** 2\
**Last updated:** [July 29, 2021, 11:08am UTC](https://discourse.julialang.org/t/num-constraints-to-return-the-total-number-of-constraints/65488 "2021-07-29T11:08:37Z")

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Apparently num\_constraints only accepts concrete types, which means it’s not straightforward to return the total number of constraints in the model. Is there a straightforward way of doing this, or do we need to resort t…

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## [\[ANN\] ERFA.jl 1.0 (and 1.1) – Essential Routines for Fundamental Astronomy](https://discourse.julialang.org/t/ann-erfa-jl-1-0-and-1-1-essential-routines-for-fundamental-astronomy/65424)

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**Author:** [@helgee](https://discourse.julialang.org/u/helgee)\
**Replies:** 0\
**Last updated:** [July 28, 2021, 9:18am UTC](https://discourse.julialang.org/t/ann-erfa-jl-1-0-and-1-1-essential-routines-for-fundamental-astronomy/65424 "2021-07-28T09:18:21Z")

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The venerable ERFA.jl has reached version 1.0 :tada: For those who have not heard about it, yet, it is a Julia wrapper for liberfa which in turn is the open-source version of the Standards of Fundamental Astronomy (SOFA…

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## [CuArray supports bits type error when performing automatic differentiation in sciml\_train (possibly due to array reshaping)](https://discourse.julialang.org/t/cuarray-supports-bits-type-error-when-performing-automatic-differentiation-in-sciml-train-possibly-due-to-array-reshaping/65389)

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**Author:** [@timothypraditia](https://discourse.julialang.org/u/timothypraditia)\
**Replies:** 6\
**Last updated:** [July 28, 2021, 8:39pm UTC](https://discourse.julialang.org/t/cuarray-supports-bits-type-error-when-performing-automatic-differentiation-in-sciml-train-possibly-due-to-array-reshaping/65389 "2021-07-28T20:39:36Z")

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Hello everyone, I’m trying to convert my code so that it would run on GPU, but I still encountered some issues. My code is mainly using DiffEqFlux, with some array reshaping required inside the Neural ODE function itse…

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## [Lathe.jl: No Method Matching Error](https://discourse.julialang.org/t/lathe-jl-no-method-matching-error/65455)

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**Author:** [@YummyPampers2](https://discourse.julialang.org/u/YummyPampers2)\
**Replies:** 0\
**Last updated:** [July 28, 2021, 6:41pm UTC](https://discourse.julialang.org/t/lathe-jl-no-method-matching-error/65455 "2021-07-28T18:41:48Z")

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Hello Everyone: I am using Lathe:preprocess Have attempted to activate the following functions from HERE: begin mutable struct OneHotEncoder{P} \<: Lathe.preprocess.Encoder predict::P function OneHotEncoder…

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## [Line thickness, marker size scales in Makie](https://discourse.julialang.org/t/line-thickness-marker-size-scales-in-makie/65447)

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**Author:** [@keithjlee](https://discourse.julialang.org/u/keithjlee)\
**Replies:** 0\
**Last updated:** [July 28, 2021, 4:17pm UTC](https://discourse.julialang.org/t/line-thickness-marker-size-scales-in-makie/65447 "2021-07-28T16:17:35Z")

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I’m currently trying to make sense of how Makie (GLMakie) deals with scaling of element sizes. I’m trying to make a quick function that visualizes structures for finite element analysis, just simple points and lines tha…

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## [Data-formatting in and out of Flux ML model](https://discourse.julialang.org/t/data-formatting-in-and-out-of-flux-ml-model/65383)

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**Author:** [@amit1](https://discourse.julialang.org/u/amit1)\
**Replies:** 1\
**Last updated:** [July 28, 2021, 4:15pm UTC](https://discourse.julialang.org/t/data-formatting-in-and-out-of-flux-ml-model/65383 "2021-07-28T16:15:29Z")

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Hi, I am still learning the ropes of Flux framework. I have experience of tensorflow and bit of pytorch, but I am interested in Flux, mostly because of the flexibility and uniformity (no more to\_numpy and vice versa!). I…

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## [Scaling for multi-threading](https://discourse.julialang.org/t/scaling-for-multi-threading/65301)

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**Author:** [@francispoulin](https://discourse.julialang.org/u/francispoulin)\
**Replies:** 10\
**Last updated:** [July 28, 2021, 4:14pm UTC](https://discourse.julialang.org/t/scaling-for-multi-threading/65301 "2021-07-28T16:14:35Z")

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A question for @luraess and @samo . In the mini-course you gave here you give a lot of different code to solve the diffusion equation in 3D, which was a lot of fun. I know that you have shown that multi-GPU can be effic…

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## [My ConstraintSolver.jl page](https://discourse.julialang.org/t/my-constraintsolver-jl-page/65430)

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**Author:** [@Hakan\_Kjellerstrand](https://discourse.julialang.org/u/Hakan_Kjellerstrand)\
**Replies:** 2\
**Last updated:** [July 28, 2021, 12:17pm UTC](https://discourse.julialang.org/t/my-constraintsolver-jl-page/65430 "2021-07-28T12:17:38Z")

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One of my (other) Julia-related interests is Ole Kröger’s Home · ConstraintSolver . My ConstraintSolver.jl models are here: My Julia ConstraintSolver.jl page , also available at https://github.com/hakank/hakank/tree/mas…

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## [Converting a Time() to an standardized Int64 or Float64](https://discourse.julialang.org/t/converting-a-time-to-an-standardized-int64-or-float64/65404)

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**Author:** [@YummyPampers2](https://discourse.julialang.org/u/YummyPampers2)\
**Replies:** 7\
**Last updated:** [July 28, 2021, 9:11am UTC](https://discourse.julialang.org/t/converting-a-time-to-an-standardized-int64-or-float64/65404 "2021-07-28T09:11:06Z")

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Hello Everyone: I instantiated a variable using Sprints = Time(00,01,00):Dates.Minute(1):Time(01,00,00) and created a data frame with: Allstars = DataFrame(Id = 1:10, BestTimes = rand(Sprints, 10)) How could I conve…

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## [Changing Gtk widget border/background colors](https://discourse.julialang.org/t/changing-gtk-widget-border-background-colors/5126)

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**Author:** [@jpsamaroo](https://discourse.julialang.org/u/jpsamaroo)\
**Replies:** 3\
**Last updated:** [July 28, 2021, 8:40am UTC](https://discourse.julialang.org/t/changing-gtk-widget-border-background-colors/5126 "2021-07-28T08:40:15Z")

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I’m having a bit of difficulty trying to understand how one would set the background or border color of a widget with Gtk.jl. I’ve taken a look at this issue, but haven’t been able to make it work with Julia 0.6 and Gtk …

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## [Precise control of navigation in 3D scene in Makie?](https://discourse.julialang.org/t/precise-control-of-navigation-in-3d-scene-in-makie/62387)

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**Author:** [@hacklint](https://discourse.julialang.org/u/hacklint)\
**Replies:** 7\
**Last updated:** [July 27, 2021, 11:27pm UTC](https://discourse.julialang.org/t/precise-control-of-navigation-in-3d-scene-in-makie/62387 "2021-07-27T23:27:56Z")

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Hi, I’m starting to visualize a collection of meshes in Makie, currently using the mouse to navigate the content. However, after a while the rotate, drag and zoom performed usually make me end up with parts of the conte…

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## [Styling AlgebraOfGraphics boxplots](https://discourse.julialang.org/t/styling-algebraofgraphics-boxplots/65335)

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**Author:** [@jbmuir](https://discourse.julialang.org/u/jbmuir)\
**Replies:** 13\
**Last updated:** [July 27, 2021, 10:30pm UTC](https://discourse.julialang.org/t/styling-algebraofgraphics-boxplots/65335 "2021-07-27T22:30:53Z")

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I’m amazed how easy it is to make complex and good-looking figures using AlgebraOfGraphics - it is still a little opaque as to how to use custom styles in them though. I’d like to be able to change the colors in this…

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## [Adding a linear or logistic equation to a curve plot](https://discourse.julialang.org/t/adding-a-linear-or-logistic-equation-to-a-curve-plot/65348)

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**Author:** [@YummyPampers2](https://discourse.julialang.org/u/YummyPampers2)\
**Replies:** 3\
**Last updated:** [July 27, 2021, 5:50pm UTC](https://discourse.julialang.org/t/adding-a-linear-or-logistic-equation-to-a-curve-plot/65348 "2021-07-27T17:50:03Z")

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Hello Everyone: Is there an approach to displaying the regression equation on a curve plot? I would like to avoid using PyCall.jl or SciKitLearn.jl. I am using StatsPlots.jl with a PlotlyJS backend(). Initially, I …

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## [Understanding MultiAgent in ReinforcementLearning.jl](https://discourse.julialang.org/t/understanding-multiagent-in-reinforcementlearning-jl/65269)

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**Author:** [@thae](https://discourse.julialang.org/u/thae)\
**Replies:** 2\
**Last updated:** [July 27, 2021, 2:04pm UTC](https://discourse.julialang.org/t/understanding-multiagent-in-reinforcementlearning-jl/65269 "2021-07-27T14:04:44Z")

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Hello, let it be known that I know little about Julia and even less about Reinforcement Learning. I’ve written an environment so trivial it is meaningless just to understand how everything fits together. It’s a four-pla…

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## [Need Diffractor.jl for State-of-the-Art Deep Learning Model](https://discourse.julialang.org/t/need-diffractor-jl-for-state-of-the-art-deep-learning-model/59423)

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**Author:** [@Freddy\_Chua](https://discourse.julialang.org/u/Freddy_Chua)\
**Replies:** 12\
**Last updated:** [July 27, 2021, 11:03am UTC](https://discourse.julialang.org/t/need-diffractor-jl-for-state-of-the-art-deep-learning-model/59423 "2021-07-27T11:03:15Z")

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Hi, I hope to beta test for your Diffractor.jl next generation AD. I am a co-author of DeepCPCFG \[2103.05908\] DeepCPCFG: Deep Learning and Context Free Grammars for End-to-End Information Extraction. This research is a…

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## [Unable to write DataFrame to Parquet or Arrow?](https://discourse.julialang.org/t/unable-to-write-dataframe-to-parquet-or-arrow/65284)

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**Author:** [@NowanIlfideme](https://discourse.julialang.org/u/NowanIlfideme)\
**Replies:** 7\
**Last updated:** [July 27, 2021, 9:07am UTC](https://discourse.julialang.org/t/unable-to-write-dataframe-to-parquet-or-arrow/65284 "2021-07-27T09:07:11Z")

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Hi, I’m trying to save a large DataFrame. Long story short, only the CSV and Feather packages seem to work at all, but I would prefer Arrow or Parquet. I’ve installed Parquet.jl and Arrow.jl, but they fail to work. I ass…

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## [My Turing.jl models](https://discourse.julialang.org/t/my-turing-jl-models/65258)

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**Author:** [@Hakan\_Kjellerstrand](https://discourse.julialang.org/u/Hakan_Kjellerstrand)\
**Replies:** 2\
**Last updated:** [July 26, 2021, 4:36pm UTC](https://discourse.julialang.org/t/my-turing-jl-models/65258 "2021-07-26T16:36:03Z")

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I have now finished porting most of my WebPPL and BLOG models to Turing.jl. They are collected at My Julia Turing.jl (probabilistic programming) page and also available at my GitHub page: https://github.com/hakank/hakank…

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## [CUDA.@cuStaticSharedMem returning a Structure of Arrays](https://discourse.julialang.org/t/cuda-custaticsharedmem-returning-a-structure-of-arrays/65307)

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**Author:** [@shiroghost](https://discourse.julialang.org/u/shiroghost)\
**Replies:** 0\
**Last updated:** [July 26, 2021, 2:13pm UTC](https://discourse.julialang.org/t/cuda-custaticsharedmem-returning-a-structure-of-arrays/65307 "2021-07-26T14:13:30Z")

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Working on the GPU I usually find convenient to use Structure of Arrays. I use GitHub - JuliaArrays/StructArrays.jl: Efficient implementation of struct arrays in Julia For example, I use: struct pt x::Float64 Y::Float6…

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## [Generic Affine Expression in a constraint](https://discourse.julialang.org/t/generic-affine-expression-in-a-constraint/65275)

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**Author:** [@Daniel\_Villamar](https://discourse.julialang.org/u/Daniel_Villamar)\
**Replies:** 1\
**Last updated:** [July 26, 2021, 9:00am UTC](https://discourse.julialang.org/t/generic-affine-expression-in-a-constraint/65275 "2021-07-26T09:00:34Z")

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I am having a hard time with a NL model that I am creating. My model uses matrices and therefore my variable and constraints are arrays. I want to create an array of constraints that includes some calculations with my v…

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## [About @connectors](https://discourse.julialang.org/t/about-connectors/65083)

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**Author:** [@juliascrub](https://discourse.julialang.org/u/juliascrub)\
**Replies:** 3\
**Last updated:** [July 26, 2021, 12:47am UTC](https://discourse.julialang.org/t/about-connectors/65083 "2021-07-26T00:47:08Z")

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Ive got a model defined as a connector @connector function Pin(iv::Num; name) ... end And another model composed of these connectors: function ModelWithConnectors(iv::Num; name) @named a = Pin(iv) @named b …

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## [Excel data to dataframes](https://discourse.julialang.org/t/excel-data-to-dataframes/65264)

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**Author:** [@mjanun](https://discourse.julialang.org/u/mjanun)\
**Replies:** 16\
**Last updated:** [July 25, 2021, 7:21pm UTC](https://discourse.julialang.org/t/excel-data-to-dataframes/65264 "2021-07-25T19:21:39Z")

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I have some data in different columns of an Excel sheet. I want to read the different columns into separate dataframes. I know the the column name/number where the data for each dataframe starts but not number of rows of…

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## [About DataFrame(array\_of\_dict)](https://discourse.julialang.org/t/about-dataframe-array-of-dict/65253)

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**Author:** [@rocco\_sprmnt21](https://discourse.julialang.org/u/rocco_sprmnt21)\
**Replies:** 5\
**Last updated:** [July 25, 2021, 6:45pm UTC](https://discourse.julialang.org/t/about-dataframe-array-of-dict/65253 "2021-07-25T18:45:30Z")

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using AlphaVantage, DataFrames apikey\_AV = AlphaVantage.global\_key!("5J16OULI0KY026M4"); tickerList = \["AAPL","MSFT"\]; StockHistoryRawJson = AlphaVantage.time\_series\_daily\_adjusted.(Stocks.tickerList, outputsize="compac…

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## [Sparse Feed Forward NN](https://discourse.julialang.org/t/sparse-feed-forward-nn/33203)

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**Author:** [@olszewskip](https://discourse.julialang.org/u/olszewskip)\
**Replies:** 3\
**Last updated:** [July 25, 2021, 1:27pm UTC](https://discourse.julialang.org/t/sparse-feed-forward-nn/33203 "2021-07-25T13:27:10Z")

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Hi! I have a question about (hypothetical) sparse layers in feedforward neural neworks: How would I go about using sparse array in place of W(eights) and b(iases) in the Flux’es Dense layer? What I imagine is that I hav…

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## [Using Pixel buffer objects to update textures in OpenGl](https://discourse.julialang.org/t/using-pixel-buffer-objects-to-update-textures-in-opengl/65260)

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**Author:** [@Jakub\_Mitura](https://discourse.julialang.org/u/Jakub_Mitura)\
**Replies:** 0\
**Last updated:** [July 25, 2021, 11:25am UTC](https://discourse.julialang.org/t/using-pixel-buffer-objects-to-update-textures-in-opengl/65260 "2021-07-25T11:25:05Z")

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Hello I looked into GL/GLAbstraction.jl package and as far as I see texture updating is done by glTexSubImage2D , yet why Pixel buffer objects are not used? Is there some reason? Frankly I tried to implement the pixel b…

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## [JuMP is slow in generating block PSD constraints](https://discourse.julialang.org/t/jump-is-slow-in-generating-block-psd-constraints/65186)

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**Author:** [@Thomas](https://discourse.julialang.org/u/Thomas)\
**Replies:** 2\
**Last updated:** [July 24, 2021, 2:48pm UTC](https://discourse.julialang.org/t/jump-is-slow-in-generating-block-psd-constraints/65186 "2021-07-24T14:48:41Z")

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Could an expert help me speed up the following code? In particular, Have I used the performance tips (https://jump.dev/JuMP.jl/stable/tutorials/Getting%20started/performance\_tips/) correctly? That is only generate exp…

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