# Specific Domains

**URL:** https://discourse.julialang.org/c/domain/10.md?no_subcategories=false&page=557

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**Page:** 558

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## [Request routing (mux) design related](https://discourse.julialang.org/t/request-routing-mux-design-related/5022)

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**Author:** [@Sarvjeet](https://discourse.julialang.org/u/Sarvjeet)\
**Replies:** 2\
**Last updated:** [July 24, 2017, 9:24pm UTC](https://discourse.julialang.org/t/request-routing-mux-design-related/5022 "2017-07-24T21:24:30Z")

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I think we can adopt the design and the underlying implementatation from the gorilla toolkit in Go language, here. It’s a fully fledged routing lib with all the required functionalities. Thoughts ? @quinnj @MikeInnes

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## [PyPlot KeyError with simple plot in Julia 0.6](https://discourse.julialang.org/t/pyplot-keyerror-with-simple-plot-in-julia-0-6/4985)

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**Author:** [@ko56](https://discourse.julialang.org/u/ko56)\
**Replies:** 7\
**Last updated:** [July 21, 2017, 9:11pm UTC](https://discourse.julialang.org/t/pyplot-keyerror-with-simple-plot-in-julia-0-6/4985 "2017-07-21T21:11:04Z")

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julia\> using Plots julia\> pyplot() Plots.PyPlotBackend() julia\> Pkg.status(“PyPlot”) PyPlot 2.3.2 julia\> plot(rand(10), \[rand(10), rand(10)\]) Error showing value of type Plots.Plot{Plots.PyP…

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## [Creating custom DataFrame types](https://discourse.julialang.org/t/creating-custom-dataframe-types/4992)

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**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\
**Replies:** 4\
**Last updated:** [July 21, 2017, 2:55pm UTC](https://discourse.julialang.org/t/creating-custom-dataframe-types/4992 "2017-07-21T14:55:46Z")

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I am putting some effort to include a special DataFrame type in my package that tracks columns representing spatial coordinates: struct GeoData data::AbstractDataFrame coordnames::Vector{Symbol} end I can then defi…

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## [Genomic Interval Metadata & Annotation](https://discourse.julialang.org/t/genomic-interval-metadata-annotation/4721)

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**Author:** [@snystrom](https://discourse.julialang.org/u/snystrom)\
**Replies:** 9\
**Last updated:** [July 21, 2017, 2:24am UTC](https://discourse.julialang.org/t/genomic-interval-metadata-annotation/4721 "2017-07-21T02:24:45Z")

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Hi, Pretty new to Julia but looking forward to its continued growth and use for genomic data. Given that the current BioJulia documentation is a bit sparse, I wanted to get the opinion of people who are more familiar wi…

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## [Query.jl: Automatize multiple @select at once](https://discourse.julialang.org/t/query-jl-automatize-multiple-select-at-once/4948)

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**Author:** [@kaslusimoes](https://discourse.julialang.org/u/kaslusimoes)\
**Replies:** 5\
**Last updated:** [July 20, 2017, 5:37pm UTC](https://discourse.julialang.org/t/query-jl-automatize-multiple-select-at-once/4948 "2017-07-20T17:37:47Z")

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Suppose I have a DataFrame with a great number of fields and the number of these columns I want to select using Query.jl. is also large. Is there any way to automatize this? For example, I have a vector v naming the fie…

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## [Visualize 3D mesh with texture](https://discourse.julialang.org/t/visualize-3d-mesh-with-texture/4671)

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**Author:** [@Loic\_Chappaz](https://discourse.julialang.org/u/Loic_Chappaz)\
**Replies:** 21\
**Last updated:** [July 19, 2017, 8:28pm UTC](https://discourse.julialang.org/t/visualize-3d-mesh-with-texture/4671 "2017-07-19T20:28:54Z")

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Hi all, I am trying to visualize 3D CAD objects in Julia. Context: I have a CAD model for a spacecraft and I want to display it in my Julia application. So far, I can convert the native CAD file into an .stl or .obj fi…

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## [Announcement: GeoStats.jl](https://discourse.julialang.org/t/announcement-geostats-jl/4098)

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**Author:** [@juliohm](https://discourse.julialang.org/u/juliohm)\
**Replies:** 7\
**Last updated:** [July 19, 2017, 6:44pm UTC](https://discourse.julialang.org/t/announcement-geostats-jl/4098 "2017-07-19T18:44:20Z")

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Dear all, I am happy to announce GeoStats.jl, a package with high-performance implementations of geostatistical algorithms for the Julia programming language. It is in its initial development, and currently only contain…

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## [Redraw figure from PyPlot.PyObject](https://discourse.julialang.org/t/redraw-figure-from-pyplot-pyobject/4929)

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**Author:** [@slowbrain](https://discourse.julialang.org/u/slowbrain)\
**Replies:** 0\
**Last updated:** [July 18, 2017, 2:14pm UTC](https://discourse.julialang.org/t/redraw-figure-from-pyplot-pyobject/4929 "2017-07-18T14:14:27Z")

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Let’s assume I’ve created plot using PyPlot at the end of my script ... # script to get "data" for plot using PyPlot p = plt\[:plot\](data) and then I close the GUI window. I wonder if there is any way to display/save p…

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## [MXNet.jl - weighted classes in SoftmaxOutput](https://discourse.julialang.org/t/mxnet-jl-weighted-classes-in-softmaxoutput/4925)

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**Author:** [@dilumaluthge](https://discourse.julialang.org/u/dilumaluthge)\
**Replies:** 0\
**Last updated:** [July 18, 2017, 12:15pm UTC](https://discourse.julialang.org/t/mxnet-jl-weighted-classes-in-softmaxoutput/4925 "2017-07-18T12:15:40Z")

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I’m using MXNet.jl to write a binary classifier for a problem with class imbalance. I’d like to weight the two classes unequally when calculating the loss (i.e. a false positive would be weighted differently than a false…

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## [Plots.jl error bar bar()](https://discourse.julialang.org/t/plots-jl-error-bar-bar/4908)

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**Author:** [@iara\_iapc](https://discourse.julialang.org/u/iara_iapc)\
**Replies:** 5\
**Last updated:** [July 18, 2017, 1:53am UTC](https://discourse.julialang.org/t/plots-jl-error-bar-bar/4908 "2017-07-18T01:53:42Z")

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Hello everyone I have a little problem. How to put the yerr in the bar chart? The code below does not work :frowning: using Plots plotlyjs() bar\_plot = bar() data = \[(rand()+1) \* randn(n) + i for i in 1:5\] for i = 1…

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## [Dirichlet Process Mixture Models (DPGMM)](https://discourse.julialang.org/t/dirichlet-process-mixture-models-dpgmm/4902)

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**Author:** [@grero](https://discourse.julialang.org/u/grero)\
**Replies:** 1\
**Last updated:** [July 17, 2017, 1:43pm UTC](https://discourse.julialang.org/t/dirichlet-process-mixture-models-dpgmm/4902 "2017-07-17T13:43:32Z")

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I wanted to try out DPGMM as a way to cluster some data I’m working on, and I came across this package: https://github.com/sbos/DirichletProcessMixtures.jl. I’m not sure if anyone is still maintaining that package, thou…

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## [Color and Legend with Gadfly - how can I control them?](https://discourse.julialang.org/t/color-and-legend-with-gadfly-how-can-i-control-them/3168)

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**Author:** [@PeterJacko](https://discourse.julialang.org/u/PeterJacko)\
**Replies:** 5\
**Last updated:** [July 17, 2017, 9:23am UTC](https://discourse.julialang.org/t/color-and-legend-with-gadfly-how-can-i-control-them/3168 "2017-07-17T09:23:13Z")

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I would like to ask you if you have any advice… as I can’t sort out one issue when creating plots with Gadfly in Julia v0.5. I need to plot matrices, which have discrete values (from 0 to 127), so that each value is plo…

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## [Memory-cheap way to calculate 1D-formated, non-zero only histogram of sparse data?](https://discourse.julialang.org/t/memory-cheap-way-to-calculate-1d-formated-non-zero-only-histogram-of-sparse-data/4885)

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**Author:** [@Datseris](https://discourse.julialang.org/u/Datseris)\
**Replies:** 5\
**Last updated:** [July 17, 2017, 8:50am UTC](https://discourse.julialang.org/t/memory-cheap-way-to-calculate-1d-formated-non-zero-only-histogram-of-sparse-data/4885 "2017-07-17T08:50:03Z")

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Halo, I’ve noticed that I run out of memory extremely quickly when calculating a high-resolution histogram of three dimensional data (using StatsBase). I guess the reason is that the size of the output is proportional t…

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## [Getting JuMP.Variable from variable name "x\[1\]"](https://discourse.julialang.org/t/getting-jump-variable-from-variable-name-x-1/4875)

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**Author:** [@mohamed82008](https://discourse.julialang.org/u/mohamed82008)\
**Replies:** 3\
**Last updated:** [July 15, 2017, 8:52pm UTC](https://discourse.julialang.org/t/getting-jump-variable-from-variable-name-x-1/4875 "2017-07-15T20:52:29Z")

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Is there a straightforward way to get a JuMP.Variable object from the model using the variable name or column index that does not involve the relatively inefficient eval(parse(vname))?

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## [Juno's enhanced display items are out of order](https://discourse.julialang.org/t/junos-enhanced-display-items-are-out-of-order/4841)

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**Author:** [@tuckermcclure](https://discourse.julialang.org/u/tuckermcclure)\
**Replies:** 2\
**Last updated:** [July 15, 2017, 6:11pm UTC](https://discourse.julialang.org/t/junos-enhanced-display-items-are-out-of-order/4841 "2017-07-15T18:11:51Z")

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I have a mix of println and things that trigger “enhanced display” features in Juno, like displaying a warning. The enhanced display items show up in the console out of order. E.g., for: println("Hi."); display(:a\_symbo…

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## [How to deal with the lack of an explicit Expression type (present in CVX) in Convex.jl?](https://discourse.julialang.org/t/how-to-deal-with-the-lack-of-an-explicit-expression-type-present-in-cvx-in-convex-jl/4854)

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**Author:** [@falbarelli](https://discourse.julialang.org/u/falbarelli)\
**Replies:** 8\
**Last updated:** [July 14, 2017, 9:09pm UTC](https://discourse.julialang.org/t/how-to-deal-with-the-lack-of-an-explicit-expression-type-present-in-cvx-in-convex-jl/4854 "2017-07-14T21:09:58Z")

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Hello, I am a new user of Convex.jl and I am trying to port some Matlab code I wrote for CVX. Basically one of the variables of my problem is a matrix, but my constraints involve not the variable matrix itself, but two …

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## [Need help understand error status of Ipopt](https://discourse.julialang.org/t/need-help-understand-error-status-of-ipopt/4771)

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**Author:** [@xqrongm](https://discourse.julialang.org/u/xqrongm)\
**Replies:** 7\
**Last updated:** [July 14, 2017, 8:03pm UTC](https://discourse.julialang.org/t/need-help-understand-error-status-of-ipopt/4771 "2017-07-14T20:03:11Z")

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I’m trying to use JuMP and Ipopt for this optimization problem below. I keep getting errors like “Infeasible\_Problem\_Detected”, “Search\_Direction\_Becomes\_Too\_Small”, “Restoration\_Failed”, for various datasets. I read I…

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## [ImageDraw Boundingbox MWE](https://discourse.julialang.org/t/imagedraw-boundingbox-mwe/4838)

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**Author:** [@rand5](https://discourse.julialang.org/u/rand5)\
**Replies:** 3\
**Last updated:** [July 14, 2017, 1:04pm UTC](https://discourse.julialang.org/t/imagedraw-boundingbox-mwe/4838 "2017-07-14T13:04:22Z")

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Could anyone share a MWE using ImageDraw or similar to plot boundboxes on an image? The bounding boxes were generated using Images.component\_boxes I’ve been looking at the Path methods in ImageDraw, but it doesn’t seem…

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## [Pkg.update() seems to have broken my Plots install](https://discourse.julialang.org/t/pkg-update-seems-to-have-broken-my-plots-install/2050)

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**Author:** [@purplishrock](https://discourse.julialang.org/u/purplishrock)\
**Replies:** 4\
**Last updated:** [July 13, 2017, 9:31pm UTC](https://discourse.julialang.org/t/pkg-update-seems-to-have-broken-my-plots-install/2050 "2017-07-13T21:31:06Z")

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Given the trouble i was having with pyplot i decided to try and intall GR it did this: INFO: Precompiling module GR. WARNING: Module Compat with uuid 3037559065285 is missing from the cache. This may mean module Compat…

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## [Genomic Feature Heatmap](https://discourse.julialang.org/t/genomic-feature-heatmap/4824)

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**Author:** [@snystrom](https://discourse.julialang.org/u/snystrom)\
**Replies:** 0\
**Last updated:** [July 12, 2017, 9:37pm UTC](https://discourse.julialang.org/t/genomic-feature-heatmap/4824 "2017-07-12T21:37:18Z")

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Is it possible to move the location of a legend for heatmaps using Plot()? I have tried every available backend and the legend = :bottom (or any other :direction) does not work. legend = false behaves as expected, howeve…

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## [How is the data ecosystem right now for large datasets?](https://discourse.julialang.org/t/how-is-the-data-ecosystem-right-now-for-large-datasets/4281)

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**Author:** [@aaowens](https://discourse.julialang.org/u/aaowens)\
**Replies:** 35\
**Last updated:** [July 13, 2017, 3:08pm UTC](https://discourse.julialang.org/t/how-is-the-data-ecosystem-right-now-for-large-datasets/4281 "2017-07-13T15:08:42Z")

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I am currently working with a dataset of several hundred million observations in Stata, which as I am aware is not particularly efficient at handling datasets this large. It can take close to an hour to process a few spl…

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## [How to filter a df with startswith() in a field?](https://discourse.julialang.org/t/how-to-filter-a-df-with-startswith-in-a-field/4837)

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**Author:** [@sylvaticus](https://discourse.julialang.org/u/sylvaticus)\
**Replies:** 1\
**Last updated:** [July 13, 2017, 2:06pm UTC](https://discourse.julialang.org/t/how-to-filter-a-df-with-startswith-in-a-field/4837 "2017-07-13T14:06:30Z")

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Nor these two approach works: df = DataFrame(field1 = \["abc", "abb", "acc"\]) pattern = "ab" ps = sizeof(pattern) filteredDf = myData\[df\[:field1\]\[1:ps\] .== pattern), :\] filteredDf = myData\[startswith(df\[:field1\],patte…

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## [PriorityQueue and containers](https://discourse.julialang.org/t/priorityqueue-and-containers/4796)

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**Author:** [@sambitdash](https://discourse.julialang.org/u/sambitdash)\
**Replies:** 3\
**Last updated:** [July 12, 2017, 5:18pm UTC](https://discourse.julialang.org/t/priorityqueue-and-containers/4796 "2017-07-12T17:18:06Z")

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Hi All, While looking at PriorityQueue implementation in package DataStructures, I realized the algorithm is biased to underlying implementation. The implementation maintains a Dict and index array as a paired heap arr…

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## [Usage of different types of weights](https://discourse.julialang.org/t/usage-of-different-types-of-weights/4780)

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**Author:** [@jeffwong](https://discourse.julialang.org/u/jeffwong)\
**Replies:** 12\
**Last updated:** [July 12, 2017, 4:54pm UTC](https://discourse.julialang.org/t/usage-of-different-types-of-weights/4780 "2017-07-12T16:54:44Z")

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The weights.jl file describes three types of weights: frequency weights, probability weights, and analytic weights. This is an amazing feature to Julia, as only commercial software like STATA and SAS understand the diff…

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## [Converting from Wide to Long format](https://discourse.julialang.org/t/converting-from-wide-to-long-format/4811)

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**Author:** [@Juan](https://discourse.julialang.org/u/Juan)\
**Replies:** 1\
**Last updated:** [July 12, 2017, 3:43pm UTC](https://discourse.julialang.org/t/converting-from-wide-to-long-format/4811 "2017-07-12T15:43:05Z")

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Hello. Some time ago I dealt with the problem of converting a large dataset from Wide format to Long format, sometimes called pivoting. I did that first steps in R but it’s too slow. Let’s say we have this toy example…

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## [Imfill Equivalent](https://discourse.julialang.org/t/imfill-equivalent/4772)

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**Author:** [@rand5](https://discourse.julialang.org/u/rand5)\
**Replies:** 1\
**Last updated:** [July 11, 2017, 11:47am UTC](https://discourse.julialang.org/t/imfill-equivalent/4772 "2017-07-11T11:47:47Z")

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I am aware of the erode/dilate and opening/closing functionality in the Images package, but is there an equivalent to Matlab’s imfill to fill image regions and holes?

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## [Irfft with A\_mul\_B! messes up its input](https://discourse.julialang.org/t/irfft-with-a-mul-b-messes-up-its-input/4762)

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**Author:** [@navidcy](https://discourse.julialang.org/u/navidcy)\
**Replies:** 1\
**Last updated:** [July 10, 2017, 2:53pm UTC](https://discourse.julialang.org/t/irfft-with-a-mul-b-messes-up-its-input/4762 "2017-07-10T14:53:01Z")

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Using A\_mul\_B! seems to be messing up it’s input. I attach a .jl file (INPUT) and the output I get on my machine. The output’s last line is the one which is puzzling! INPUT # Code snippet to test nx, ny = 8, 8 nk, nl =…

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## [Generic Julia FFT](https://discourse.julialang.org/t/generic-julia-fft/4759)

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**Author:** [@MikaelSlevinsky](https://discourse.julialang.org/u/MikaelSlevinsky)\
**Replies:** 1\
**Last updated:** [July 10, 2017, 2:48pm UTC](https://discourse.julialang.org/t/generic-julia-fft/4759 "2017-07-10T14:48:59Z")

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Now that FFTW.jl and AbstractFFTs.jl are being moved out of Base for 0.7, (where) will a pure Julia FFT be implemented?

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## [Sparse arrays and function arrays in CUDAnative.jl](https://discourse.julialang.org/t/sparse-arrays-and-function-arrays-in-cudanative-jl/4754)

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**Author:** [@mohamed82008](https://discourse.julialang.org/u/mohamed82008)\
**Replies:** 12\
**Last updated:** [July 10, 2017, 12:32pm UTC](https://discourse.julialang.org/t/sparse-arrays-and-function-arrays-in-cudanative-jl/4754 "2017-07-10T12:32:08Z")

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Is there any simple way to make, write to and read from sparse arrays on the device through CUDAnative.jl? Also, is it possible to define an array of device functions that is moved to the device and then each function c…

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## [Help with a little query](https://discourse.julialang.org/t/help-with-a-little-query/4723)

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**Author:** [@ssfrr](https://discourse.julialang.org/u/ssfrr)\
**Replies:** 8\
**Last updated:** [July 10, 2017, 12:23pm UTC](https://discourse.julialang.org/t/help-with-a-little-query/4723 "2017-07-10T12:23:59Z")

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I don’t generally work with much tabular data, so I could use some input on the best way to do a little CSV processing task that popped up today. The data I’m working with is here, and is evaluation metrics for a bunch …

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