# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=432

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**Page:** 433

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## [Plotting graphs with movable nodes](https://discourse.julialang.org/t/plotting-graphs-with-movable-nodes/43615)

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**Author:** [@Tomas\_Pevny](https://discourse.julialang.org/u/Tomas_Pevny)\
**Replies:** 0\
**Last updated:** [July 24, 2020, 12:52pm UTC](https://discourse.julialang.org/t/plotting-graphs-with-movable-nodes/43615 "2020-07-24T12:52:48Z")

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Hi All, I would like to ask, of anyone knows about a simple way, how draw a graph, e.g. like this one such that I can move the vertices? Thanks a lot, Tomas

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## [Trying variety of Solvers](https://discourse.julialang.org/t/trying-variety-of-solvers/43567)

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**Author:** [@mayar](https://discourse.julialang.org/u/mayar)\
**Replies:** 2\
**Last updated:** [July 24, 2020, 11:45am UTC](https://discourse.julialang.org/t/trying-variety-of-solvers/43567 "2020-07-24T11:45:31Z")

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hello there, I have been looking for some solver to try with my problem ( non convex NLP) After finishing the modelling stage, I was really impressed by the easiness of using a solver like Ipopt with JuMP, but now to l…

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## [ERROR: could not load library libcutensor.so](https://discourse.julialang.org/t/error-could-not-load-library-libcutensor-so/43020)

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**Author:** [@samo](https://discourse.julialang.org/u/samo)\
**Replies:** 19\
**Last updated:** [July 24, 2020, 6:24am UTC](https://discourse.julialang.org/t/error-could-not-load-library-libcutensor-so/43020 "2020-07-24T06:24:26Z")

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After a fresh installation of CUDA.jl 1.1/1.0, we got the following error on a cluster when trying to precompile a package that has CUDA in its dependencies: \[ Info: Precompiling ParallelStencil \[94395366-693c-11ea-3b26…

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## [SDP relaxation in PowerModelsAneex](https://discourse.julialang.org/t/sdp-relaxation-in-powermodelsaneex/41898)

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**Author:** [@Rasoul](https://discourse.julialang.org/u/Rasoul)\
**Replies:** 6\
**Last updated:** [July 23, 2020, 11:37pm UTC](https://discourse.julialang.org/t/sdp-relaxation-in-powermodelsaneex/41898 "2020-07-23T23:37:11Z")

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Hi All, I am wondering if there is an SDP relaxation of the OPF problem in PowerModelsAnnex? If there is no such function, I would appreciate any guide for implementing that in the PowerModelsAnnex. I have noticed ther…

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## [Large initial values in DAE system](https://discourse.julialang.org/t/large-initial-values-in-dae-system/43592)

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**Author:** [@lob](https://discourse.julialang.org/u/lob)\
**Replies:** 0\
**Last updated:** [July 23, 2020, 10:17pm UTC](https://discourse.julialang.org/t/large-initial-values-in-dae-system/43592 "2020-07-23T22:17:13Z")

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Hi all, I am trying to solve a DAE system using DifferentialEquations.jl where initial values can be relatively large (order 1e22). The MWE below (algebraic equations omitted) solves fine up to n0\[1\] = 1e15 but throws a…

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## [How to define a heuristic callback using JuMP?](https://discourse.julialang.org/t/how-to-define-a-heuristic-callback-using-jump/43322)

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**Author:** [@Gaiato](https://discourse.julialang.org/u/Gaiato)\
**Replies:** 8\
**Last updated:** [July 23, 2020, 9:10pm UTC](https://discourse.julialang.org/t/how-to-define-a-heuristic-callback-using-jump/43322 "2020-07-23T21:10:01Z")

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I’m trying to implement integer programming callbacks using JuMP. Basically, my heuristic callback is defined like this: function my\_heuristic\_callback(cb\_data) x\_val = \[callback\_value(cb\_data, x\_i) for x\_i in x\] x\_s…

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## [Makie seems overall broken after update?](https://discourse.julialang.org/t/makie-seems-overall-broken-after-update/38634)

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**Author:** [@chakravala](https://discourse.julialang.org/u/chakravala)\
**Replies:** 4\
**Last updated:** [July 23, 2020, 8:09pm UTC](https://discourse.julialang.org/t/makie-seems-overall-broken-after-update/38634 "2020-07-23T20:09:18Z")

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The example for mesh (and my own personal examples) are not working http://juliaplots.org/MakieReferenceImages/gallery//fem\_mesh\_2d/index.html Previously it worked fine, but now I get this error: ERROR: MethodError: n…

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## [Synthetic X-ray tomography with Julia](https://discourse.julialang.org/t/synthetic-x-ray-tomography-with-julia/19353)

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**Author:** [@KirillGerke](https://discourse.julialang.org/u/KirillGerke)\
**Replies:** 10\
**Last updated:** [July 23, 2020, 8:03pm UTC](https://discourse.julialang.org/t/synthetic-x-ray-tomography-with-julia/19353 "2020-07-23T20:03:23Z")

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Dear All, Objective: My aim is to use Julia to combine a number of complex computational tasks, one of them being creation of synthetic tomography. My search provided no results on existing Julia packages related to X-r…

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## [Install CPLEX in Julia 1.4.2 32 bits](https://discourse.julialang.org/t/install-cplex-in-julia-1-4-2-32-bits/43564)

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**Author:** [@Luis\_Tormo](https://discourse.julialang.org/u/Luis_Tormo)\
**Replies:** 5\
**Last updated:** [July 23, 2020, 6:43pm UTC](https://discourse.julialang.org/t/install-cplex-in-julia-1-4-2-32-bits/43564 "2020-07-23T18:43:05Z")

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Do you know if there is any way to install CPLEX on Julia 1.4.2 32 bit? I know I need one of the latest versions of CPLEX in 32 bit. I tried to install CPLEX 12.6.3 32bit but it gave me a lot of problems and I didn’t get…

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## [Generate Covariance Matrix with Pre-Specified Restrictions](https://discourse.julialang.org/t/generate-covariance-matrix-with-pre-specified-restrictions/43439)

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**Author:** [@zxjroger](https://discourse.julialang.org/u/zxjroger)\
**Replies:** 6\
**Last updated:** [July 23, 2020, 4:50pm UTC](https://discourse.julialang.org/t/generate-covariance-matrix-with-pre-specified-restrictions/43439 "2020-07-23T16:50:25Z")

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I have a 3 by 3 matrix of random variables and I would like to generate the covariance matrix of these 9 random variables. The restrictions are as follows: \\begin{aligned} \\operatorname{Corr}\\left(b\_{u\_{1}, d\_{1}}, b\_{…

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## [Apply boolean mask in loss function](https://discourse.julialang.org/t/apply-boolean-mask-in-loss-function/40374)

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**Author:** [@dfenn](https://discourse.julialang.org/u/dfenn)\
**Replies:** 1\
**Last updated:** [July 23, 2020, 4:26pm UTC](https://discourse.julialang.org/t/apply-boolean-mask-in-loss-function/40374 "2020-07-23T16:26:15Z")

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Is there a way to apply a boolean mask to the multidimensional arrays in a loss function using Flux? I’ve been unable to achieve this on the gpu. I’m using Julia 1.3 and Flux v0.10.4. Consider the following MWE (this is…

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## [\[ANN(s)\] HalfSpectral.jl: a convenient interface for half-spectral covariance functions, and GPMaxlik.jl: trust-region based maximum likelihood estimation for Gaussian Processes](https://discourse.julialang.org/t/ann-s-halfspectral-jl-a-convenient-interface-for-half-spectral-covariance-functions-and-gpmaxlik-jl-trust-region-based-maximum-likelihood-estimation-for-gaussian-processes/43565)

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**Author:** [@cgeoga](https://discourse.julialang.org/u/cgeoga)\
**Replies:** 0\
**Last updated:** [July 23, 2020, 4:18pm UTC](https://discourse.julialang.org/t/ann-s-halfspectral-jl-a-convenient-interface-for-half-spectral-covariance-functions-and-gpmaxlik-jl-trust-region-based-maximum-likelihood-estimation-for-gaussian-processes/43565 "2020-07-23T16:18:13Z")

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Hey all— Just a quick announcement of a couple little pieces of software that some of you may find useful or interesting. HalfSpectral.jl is a simple little package that implements half spectral covariance functions in…

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## [Preconditioner for nonlinear optimization](https://discourse.julialang.org/t/preconditioner-for-nonlinear-optimization/43558)

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**Author:** [@mleprovost](https://discourse.julialang.org/u/mleprovost)\
**Replies:** 0\
**Last updated:** [July 23, 2020, 3:14pm UTC](https://discourse.julialang.org/t/preconditioner-for-nonlinear-optimization/43558 "2020-07-23T15:14:13Z")

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Hello, I am working on the following nonlinear minimization problem: \\displaystyle{\\min\_{\\boldsymbol{c} \\in R^n}} \\mbox{ }\\frac{1}{M} \\sum\_{i=1}^{M} \\left(\\frac{1}{2} \\left\[\\boldsymbol{c}^T \\boldsymbol{f}\_0 + \\int…

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## [Count the number of evauations of the objective function](https://discourse.julialang.org/t/count-the-number-of-evauations-of-the-objective-function/43251)

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**Author:** [@Ariel\_Cruz\_Cruz](https://discourse.julialang.org/u/Ariel_Cruz_Cruz)\
**Replies:** 3\
**Last updated:** [July 23, 2020, 1:06pm UTC](https://discourse.julialang.org/t/count-the-number-of-evauations-of-the-objective-function/43251 "2020-07-23T13:06:23Z")

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Hello, I am using JuMP with the Ipopt solver to optimize certain optimization problem. And I need to get the number of evaluations of the objective function. When I run my program I get some information such as: Number …

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## [Best way to solve system of ODEs with different types in DifferentialEquations.jl](https://discourse.julialang.org/t/best-way-to-solve-system-of-odes-with-different-types-in-differentialequations-jl/43533)

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**Author:** [@tpolakovic](https://discourse.julialang.org/u/tpolakovic)\
**Replies:** 1\
**Last updated:** [July 23, 2020, 11:20am UTC](https://discourse.julialang.org/t/best-way-to-solve-system-of-odes-with-different-types-in-differentialequations-jl/43533 "2020-07-23T11:20:05Z")

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I have two fields, A (complex scalar field) and B (real vector field), which are sampled on staggered grids. This means that (in, say, three dimensions) A is an complex array with N^3 elements, while B is a real array wi…

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## [Set up Makie with Intel integrated graphics](https://discourse.julialang.org/t/set-up-makie-with-intel-integrated-graphics/40884)

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**Author:** [@johnh](https://discourse.julialang.org/u/johnh)\
**Replies:** 4\
**Last updated:** [July 23, 2020, 9:03am UTC](https://discourse.julialang.org/t/set-up-makie-with-intel-integrated-graphics/40884 "2020-07-23T09:03:47Z")

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I would like to try the fancy new InteractiveViz package. Julia 1.4 on a laptop running Fedora 32 Linux Intel Corporation HD Graphics 620 (rev 02) Glxinfo says that I am using Mesa rendering: direct rendering: Yes s…

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## [PowerModelsAnnex QC\_OPF](https://discourse.julialang.org/t/powermodelsannex-qc-opf/43459)

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**Author:** [@fnbillimoria](https://discourse.julialang.org/u/fnbillimoria)\
**Replies:** 2\
**Last updated:** [July 23, 2020, 1:21am UTC](https://discourse.julialang.org/t/powermodelsannex-qc-opf/43459 "2020-07-23T01:21:00Z")

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I am looking through the PowerModelsAnnex.jl module and particularly the src/model/opf.jl file. I noted that there is a build of a quadratically constrained opf in there? (i.e. build\_qc\_opf) Could I please confirm what …

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## [Query newest entry with Query.jl](https://discourse.julialang.org/t/query-newest-entry-with-query-jl/43385)

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**Author:** [@ohmsweetohm1](https://discourse.julialang.org/u/ohmsweetohm1)\
**Replies:** 4\
**Last updated:** [July 22, 2020, 1:14pm UTC](https://discourse.julialang.org/t/query-newest-entry-with-query-jl/43385 "2020-07-22T13:14:43Z")

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I have a table with multiple entries. For each entry I have the timestamp it was fetched and the timestamp it represents, e.g. forecasts for a specific timestamp computed at different times. I would like to query the n…

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## [Variational Inference for Multinomial output](https://discourse.julialang.org/t/variational-inference-for-multinomial-output/43498)

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**Author:** [@Farlein](https://discourse.julialang.org/u/Farlein)\
**Replies:** 0\
**Last updated:** [July 22, 2020, 2:58pm UTC](https://discourse.julialang.org/t/variational-inference-for-multinomial-output/43498 "2020-07-22T14:58:08Z")

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Hi there, I want to use Variational Inference in Turing for Multinomial output. Here are the simulated data. There are 400 2-dimension observations in 4 groups. The purpose is to identify which group each observation be…

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## [KKT condition solves the bilevel optimization problem](https://discourse.julialang.org/t/kkt-condition-solves-the-bilevel-optimization-problem/43289)

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**Author:** [@dty](https://discourse.julialang.org/u/dty)\
**Replies:** 25\
**Last updated:** [July 22, 2020, 2:36pm UTC](https://discourse.julialang.org/t/kkt-condition-solves-the-bilevel-optimization-problem/43289 "2020-07-22T14:36:38Z")

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Is there a package for solving bilevel optimization problems with KKT conditions? Specifically, the inequality constrained KKT conditions are linearized by the large M method. Finally, the two-layer problem is turned int…

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## [Regex numeric range generator](https://discourse.julialang.org/t/regex-numeric-range-generator/43472)

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**Author:** [@zhaoquanzheng](https://discourse.julialang.org/u/zhaoquanzheng)\
**Replies:** 3\
**Last updated:** [July 22, 2020, 11:50am UTC](https://discourse.julialang.org/t/regex-numeric-range-generator/43472 "2020-07-22T11:50:28Z")

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Hi everyone, I use Glob.jl to load multiple files, and I had a problem when I needed to distinguish filename by numeric range (files were saved with datetime in filename). The problem can be solved by using a regex nume…

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## [GKS problem, using Plots](https://discourse.julialang.org/t/gks-problem-using-plots/43464)

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**Author:** [@cruddy](https://discourse.julialang.org/u/cruddy)\
**Replies:** 1\
**Last updated:** [July 22, 2020, 6:21am UTC](https://discourse.julialang.org/t/gks-problem-using-plots/43464 "2020-07-22T06:21:22Z")

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Hi, I don’t have enough experience with Julia, but I was trying to make a plot and I got an error: using Plots gr() plot(x,y,linetype=:scatter, leg=false) And I get: GKS: GDP primitive not supported for X11 I’ve tr…

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## [GraphRecipes versus GraphPlot: why such a big performance disparity?](https://discourse.julialang.org/t/graphrecipes-versus-graphplot-why-such-a-big-performance-disparity/43474)

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**Author:** [@izzorts](https://discourse.julialang.org/u/izzorts)\
**Replies:** 0\
**Last updated:** [July 22, 2020, 5:38am UTC](https://discourse.julialang.org/t/graphrecipes-versus-graphplot-why-such-a-big-performance-disparity/43474 "2020-07-22T05:38:52Z")

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So, I was trying to plot some graphs and GraphPlot happened to be insufficient (I needed smaller labels than what seems to be the inferior size limit). Then I went trying to use GraphRecipes, because it seemed to have bo…

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## [VegaLite not formatting correctly](https://discourse.julialang.org/t/vegalite-not-formatting-correctly/43470)

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**Author:** [@Chris\_Anderson](https://discourse.julialang.org/u/Chris_Anderson)\
**Replies:** 0\
**Last updated:** [July 22, 2020, 3:07am UTC](https://discourse.julialang.org/t/vegalite-not-formatting-correctly/43470 "2020-07-22T03:07:40Z")

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I have plotted this graph using VegaLite, but the bars are bleeding over and obscuring everything. My code: answer |\> @vlplot(mark = {type= :bar}, x = {field = :Overall\_mean, scale = {domain = \[76,85\]}, axis = {title =…

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## [JuMP print sub-expressions](https://discourse.julialang.org/t/jump-print-sub-expressions/43021)

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**Author:** [@fnbillimoria](https://discourse.julialang.org/u/fnbillimoria)\
**Replies:** 3\
**Last updated:** [July 22, 2020, 1:48am UTC](https://discourse.julialang.org/t/jump-print-sub-expressions/43021 "2020-07-22T01:48:24Z")

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Hello, I have created an optimisation problem in JuMP with a set constraints that is created from affine and non-linear expressions. When i print() the model, the constraints show up as below. Is there any way to prin…

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## [PowerModels.jl data format](https://discourse.julialang.org/t/powermodels-jl-data-format/43460)

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**Author:** [@fnbillimoria](https://discourse.julialang.org/u/fnbillimoria)\
**Replies:** 1\
**Last updated:** [July 22, 2020, 1:18am UTC](https://discourse.julialang.org/t/powermodels-jl-data-format/43460 "2020-07-22T01:18:11Z")

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Hello, I wanted to query the branch data format for PowerModels.jl. I note that there are two fields in particular which are not mentioned in the matpower format, but do seem to be in some of the test cases. Particula…

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## [Spaces in query.jl](https://discourse.julialang.org/t/spaces-in-query-jl/8527)

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**Author:** [@RandomString123](https://discourse.julialang.org/u/RandomString123)\
**Replies:** 35\
**Last updated:** [July 21, 2020, 6:57pm UTC](https://discourse.julialang.org/t/spaces-in-query-jl/8527 "2020-07-21T18:57:50Z")

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Using DataFrames and CSV it is possible to create a table that has spaces in the column names. When this is done is there a way to reference these columns using query.jl? Or do I need to rename the columns to remove sp…

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## [Getting info from CPLEX output](https://discourse.julialang.org/t/getting-info-from-cplex-output/42582)

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**Author:** [@Codzilla](https://discourse.julialang.org/u/Codzilla)\
**Replies:** 6\
**Last updated:** [July 21, 2020, 9:39am UTC](https://discourse.julialang.org/t/getting-info-from-cplex-output/42582 "2020-07-21T09:39:15Z")

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I’m using JuMP to solve a large number of instancies with CPLEX and I would like to use the information output by CPLEX such as the number of Flow cuts applied or time spent during branch & bound. Is there any elegant wa…

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## [How do I find \`m\` and \`b\` such that \`some\_function((x) -\> m\*x + b)\` is maximized?](https://discourse.julialang.org/t/how-do-i-find-m-and-b-such-that-some-function-x-m-x-b-is-maximized/43429)

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**Author:** [@NightMachinary](https://discourse.julialang.org/u/NightMachinary)\
**Replies:** 3\
**Last updated:** [July 21, 2020, 2:51pm UTC](https://discourse.julialang.org/t/how-do-i-find-m-and-b-such-that-some-function-x-m-x-b-is-maximized/43429 "2020-07-21T14:51:51Z")

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I have the following Julia function which calculates the expected mean of some model. I want to find m and b such that EBuy(4, (x) -\> m\*x + b) is maximized. using Distributions function EBuy(λ, buy ; limDefault=10^2) …

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## [Weird ldexp performance](https://discourse.julialang.org/t/weird-ldexp-performance/43416)

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**Author:** [@Oscar\_Smith](https://discourse.julialang.org/u/Oscar_Smith)\
**Replies:** 4\
**Last updated:** [July 21, 2020, 2:12pm UTC](https://discourse.julialang.org/t/weird-ldexp-performance/43416 "2020-07-21T14:12:24Z")

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I’m trying to write a faster implimentation of exp, and along the way, I noticed that I have no idea how fast ldexp is, and my efforts to benchmark it result in madness. My code is function myexp(x::Float64) # Redu…

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