# Offtopic

**URL:** https://discourse.julialang.org/c/offtopic/29.md?no_subcategories=false&page=28

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**Page:** 29

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## [Error message when starting](https://discourse.julialang.org/t/error-message-when-starting/5358)

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**Author:** [@M\_Lampe](https://discourse.julialang.org/u/M_Lampe)\
**Replies:** 3\
**Last updated:** [August 22, 2017, 4:45pm UTC](https://discourse.julialang.org/t/error-message-when-starting/5358 "2017-08-22T16:45:04Z")

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I have troubles running Julia on my MacOS Siera. I get the following error message: ~ $ exec ‘/Applications/Julia-0.6.app/Contents/Resources/julia/bin/julia’ fatal: error thrown and no exception handler available. Base…

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## [Julialang.org website unreachable?](https://discourse.julialang.org/t/julialang-org-website-unreachable/4859)

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**Author:** [@raminammour](https://discourse.julialang.org/u/raminammour)\
**Replies:** 5\
**Last updated:** [July 14, 2017, 7:00pm UTC](https://discourse.julialang.org/t/julialang-org-website-unreachable/4859 "2017-07-14T19:00:52Z")

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I get this error: Error 503 hostname doesn't match against certificate hostname doesn't match against certificate Guru Mediation: Anyone else having this problem?

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## [Richard Hamming on great research](https://discourse.julialang.org/t/richard-hamming-on-great-research/4743)

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**Author:** [@JeffreySarnoff](https://discourse.julialang.org/u/JeffreySarnoff)\
**Replies:** 2\
**Last updated:** [July 9, 2017, 7:30am UTC](https://discourse.julialang.org/t/richard-hamming-on-great-research/4743 "2017-07-09T07:30:41Z")

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Richard Hamming (1986) the first and last paragraphs: The title of my talk is, \`\`You and Your Research.‘’ It is not about managing research, it is about how you individually do your research. I could give a talk on …

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## [Licensing speculation](https://discourse.julialang.org/t/licensing-speculation/4276)

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**Author:** [@mkborregaard](https://discourse.julialang.org/u/mkborregaard)\
**Replies:** 22\
**Last updated:** [June 16, 2017, 6:15am UTC](https://discourse.julialang.org/t/licensing-speculation/4276 "2017-06-16T06:15:38Z")

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Just to state the point clearly - it is illegal to transcribe a package from R to Julia. Fortunately, it’s mostly unnecessary :slight\_smile: Without sounding too evangelical, I’ve found that the best results always come…

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## [The naming of JuliaDB.jl](https://discourse.julialang.org/t/the-naming-of-juliadb-jl/3653)

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**Author:** [@Juan](https://discourse.julialang.org/u/Juan)\
**Replies:** 46\
**Last updated:** [June 7, 2017, 8:38pm UTC](https://discourse.julialang.org/t/the-naming-of-juliadb-jl/3653 "2017-06-07T20:38:01Z")

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Hello. Are these two different projects with the same name:? https://github.com/JuliaComputing/JuliaDB.jl https://github.com/JuliaDB Do you have any benchmark (or comparison of features) against sqlite, data.table, …

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## [Philosophy of unit tests](https://discourse.julialang.org/t/philosophy-of-unit-tests/3182)

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**Author:** [@LewisHein](https://discourse.julialang.org/u/LewisHein)\
**Replies:** 12\
**Last updated:** [May 21, 2017, 8:09am UTC](https://discourse.julialang.org/t/philosophy-of-unit-tests/3182 "2017-05-21T08:09:06Z")

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Hi all, Here is a conundrum I have about unit testing for our brilliantly conceived Julia packages (and unit testing in general) Let us assume that I have invented an amazing algorithm to compute the meaning of life. A…

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## [Using issue filtering in github](https://discourse.julialang.org/t/using-issue-filtering-in-github/1455)

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**Author:** [@lobingera](https://discourse.julialang.org/u/lobingera)\
**Replies:** 3\
**Last updated:** [January 13, 2017, 8:52am UTC](https://discourse.julialang.org/t/using-issue-filtering-in-github/1455 "2017-01-13T08:52:59Z")

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I tried to look around on the julia issues about the state of multithreading. I can filter issues to is:open and label:multithreading but i cannot filter to the milestone. If i go to the milestone page all issues are p…

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## [Modifying Source Files while Julia is Running](https://discourse.julialang.org/t/modifying-source-files-while-julia-is-running/1451)

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**Author:** [@JaredCrean2](https://discourse.julialang.org/u/JaredCrean2)\
**Replies:** 2\
**Last updated:** [January 12, 2017, 10:38pm UTC](https://discourse.julialang.org/t/modifying-source-files-while-julia-is-running/1451 "2017-01-12T22:38:30Z")

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Is it safe to modify Julia source files while Julia is running, after all include() statements have executed? I have a simulation that takes several hours to run, and want keep working on the code while it finishes, wit…

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## [Can't build julia master (light-source-dist) on a server farm anymore](https://discourse.julialang.org/t/cant-build-julia-master-light-source-dist-on-a-server-farm-anymore/1396)

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**Author:** [@Ronis\_BR](https://discourse.julialang.org/u/Ronis_BR)\
**Replies:** 2\
**Last updated:** [January 10, 2017, 3:48pm UTC](https://discourse.julialang.org/t/cant-build-julia-master-light-source-dist-on-a-server-farm-anymore/1396 "2017-01-10T15:48:27Z")

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Hi guys! I am the maintainer of julia in openSUSE. Besides the stable version, I keep building the master to track problems. I get the sources by cloning the github repository and using make light-source-dist. Hence, I…

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## [Julia set data structure](https://discourse.julialang.org/t/julia-set-data-structure/1292)

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**Author:** [@harven](https://discourse.julialang.org/u/harven)\
**Replies:** 4\
**Last updated:** [January 9, 2017, 5:02pm UTC](https://discourse.julialang.org/t/julia-set-data-structure/1292 "2017-01-09T17:02:44Z")

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I have a question on the set data structure in base Julia. As far as I understand, it is mutable, with O(1) membership, and adding an element is done with push!, which modifies the set. Is there a “functional” set colle…

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## [Speculation chained comparison optimization (possibly with outlining)](https://discourse.julialang.org/t/speculation-chained-comparison-optimization-possibly-with-outlining/1354)

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**Author:** [@Palli](https://discourse.julialang.org/u/Palli)\
**Replies:** 8\
**Last updated:** [January 9, 2017, 2:53pm UTC](https://discourse.julialang.org/t/speculation-chained-comparison-optimization-possibly-with-outlining/1354 "2017-01-09T14:53:29Z")

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\[I first saw the word outlining the other day, I assume it’s the opposite of inlining.\] It would come in handy here: \[I’m trying to fix this post, discourse messed it up\] when the “functions”, aren’t really.

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## [Optimizations of \`and\` and \`or\` (possibly new semantics for) and comparison chaining](https://discourse.julialang.org/t/optimizations-of-and-and-or-possibly-new-semantics-for-and-comparison-chaining/1364)

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**Author:** [@Palli](https://discourse.julialang.org/u/Palli)\
**Replies:** 0\
**Last updated:** [January 9, 2017, 11:17am UTC](https://discourse.julialang.org/t/optimizations-of-and-and-or-possibly-new-semantics-for-and-comparison-chaining/1364 "2017-01-09T11:17:05Z")

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A. Continuing the discussion from Does Julia ever do outlining?: @giordano Nothing prevents you from testing the condition 1 \< -3 \< 4 in this case there is no performance gain, on the contrary you’ll have perfor…

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## [Why is \[x\]or (a function call) so long/slow (not inlined)?](https://discourse.julialang.org/t/why-is-x-or-a-function-call-so-long-slow-not-inlined/1264)

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**Author:** [@Palli](https://discourse.julialang.org/u/Palli)\
**Replies:** 23\
**Last updated:** [January 5, 2017, 9:36am UTC](https://discourse.julialang.org/t/why-is-x-or-a-function-call-so-long-slow-not-inlined/1264 "2017-01-05T09:36:33Z")

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\[EDIT: you can ignore A. it was kind of a false alarm. B. is still a little interesting to me, in general, maybe not in the case of A. though.\] A. I thought I would/could optimize uppercase (and others, I found in \[PR\]…

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## [Show on custom exceptions in Julia 0.6](https://discourse.julialang.org/t/show-on-custom-exceptions-in-julia-0-6/1288)

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**Author:** [@omus](https://discourse.julialang.org/u/omus)\
**Replies:** 3\
**Last updated:** [January 4, 2017, 7:00pm UTC](https://discourse.julialang.org/t/show-on-custom-exceptions-in-julia-0-6/1288 "2017-01-04T19:00:04Z")

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I’m having some issues with throw not calling showerror on custom exceptions. I’m pretty sure that this is a bug but I just wanted to check that this wasn’t intentional: julia\> type MyUndefVarError \<: Exception …

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## [What exactly is an abstract array? (Deciding how to dispatch)](https://discourse.julialang.org/t/what-exactly-is-an-abstract-array-deciding-how-to-dispatch/1256)

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**Author:** [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)\
**Replies:** 10\
**Last updated:** [January 4, 2017, 3:55am UTC](https://discourse.julialang.org/t/what-exactly-is-an-abstract-array-deciding-how-to-dispatch/1256 "2017-01-04T03:55:01Z")

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I am trying to find out what the going definition for an AbstractArray is in order to properly choose how to dispatch. As usual, this is best understood by an example. Let’s look at two different ways of writing “the sam…

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## [Willing apprentice seeks tutor / mentor](https://discourse.julialang.org/t/willing-apprentice-seeks-tutor-mentor/1152)

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**Author:** [@pitao](https://discourse.julialang.org/u/pitao)\
**Replies:** 1\
**Last updated:** [December 26, 2016, 1:35pm UTC](https://discourse.julialang.org/t/willing-apprentice-seeks-tutor-mentor/1152 "2016-12-26T13:35:46Z")

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Hello everyone! I would love to muck in. Julia-dev would be a great new hobby! I notice the main repo has 1800 open issues against 9000 closed, which is quite a high fraction I think. I would like to have a go at clos…

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## [Mexjulia on Ubuntu](https://discourse.julialang.org/t/mexjulia-on-ubuntu/1089)

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**Author:** [@ufechner7](https://discourse.julialang.org/u/ufechner7)\
**Replies:** 8\
**Last updated:** [December 22, 2016, 9:29pm UTC](https://discourse.julialang.org/t/mexjulia-on-ubuntu/1089 "2016-12-22T21:29:26Z")

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Hello, Is there anybody around who could help to debug the following error: ufechner@TUD277255:~/00Software/mexjulia$ matlab fatal: error thrown and no exception handler available. Base.InitError(mod=:Sys, error=ErrorE…

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## [Help with tips on debugging Travis: Documenter generation of HTML](https://discourse.julialang.org/t/help-with-tips-on-debugging-travis-documenter-generation-of-html/1078)

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**Author:** [@tshort](https://discourse.julialang.org/u/tshort)\
**Replies:** 3\
**Last updated:** [December 22, 2016, 6:11pm UTC](https://discourse.julialang.org/t/help-with-tips-on-debugging-travis-documenter-generation-of-html/1078 "2016-12-22T18:11:44Z")

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I’m trying out Documenter’s ability to generate HTML, and I’m trying to get Travis to do this automatically. Documenter works fine locally, but Travis complains and doesn’t generate HTML. Does anyone have any tips for de…

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## [Did docs.julialang.org move?](https://discourse.julialang.org/t/did-docs-julialang-org-move/972)

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**Author:** [@peter.mancini](https://discourse.julialang.org/u/peter.mancini)\
**Replies:** 7\
**Last updated:** [December 22, 2016, 4:24pm UTC](https://discourse.julialang.org/t/did-docs-julialang-org-move/972 "2016-12-22T16:24:33Z")

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http://docs.julialang.org/ gives me a 404 error.

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## [Deblurring an Image using Julia (Transform from Matlab to Julia)](https://discourse.julialang.org/t/deblurring-an-image-using-julia-transform-from-matlab-to-julia/909)

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**Author:** [@cee878](https://discourse.julialang.org/u/cee878)\
**Replies:** 10\
**Last updated:** [December 21, 2016, 12:06pm UTC](https://discourse.julialang.org/t/deblurring-an-image-using-julia-transform-from-matlab-to-julia/909 "2016-12-21T12:06:17Z")

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I wrote the code for deblurring an image using the heat equation. I transformed the matlab code to Julia code. But it’s not working and I don’t really understand the error message. I get an error message: ERROR: LoadErr…

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## [Fail to build Gadfly into Julia system image](https://discourse.julialang.org/t/fail-to-build-gadfly-into-julia-system-image/1058)

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**Author:** [@AStupidBear](https://discourse.julialang.org/u/AStupidBear)\
**Replies:** 1\
**Last updated:** [December 20, 2016, 11:35pm UTC](https://discourse.julialang.org/t/fail-to-build-gadfly-into-julia-system-image/1058 "2016-12-20T23:35:20Z")

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I have put import Gadfly in userimage.jl, then use include(joinpath(JULIA\_HOME, Base.DATAROOTDIR, "julia", "build\_sysimg.jl")) build\_sysimg(default\_sysimg\_path(), "native", "C:/Users/AStupidBear/userimg.jl"; force=true)…

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## [PyPlot: how to plot up-down arrows in a figure?](https://discourse.julialang.org/t/pyplot-how-to-plot-up-down-arrows-in-a-figure/741)

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**Author:** [@songroom](https://discourse.julialang.org/u/songroom)\
**Replies:** 3\
**Last updated:** [December 17, 2016, 1:55am UTC](https://discourse.julialang.org/t/pyplot-how-to-plot-up-down-arrows-in-a-figure/741 "2016-12-17T01:55:14Z")

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## [Provide an implementation of f \*only\* if g is available](https://discourse.julialang.org/t/provide-an-implementation-of-f-only-if-g-is-available/931)

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**Author:** [@zsunberg](https://discourse.julialang.org/u/zsunberg)\
**Replies:** 7\
**Last updated:** [December 16, 2016, 3:52pm UTC](https://discourse.julialang.org/t/provide-an-implementation-of-f-only-if-g-is-available/931 "2016-12-16T15:52:16Z")

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Hi, The interface to my package includes two functions, f, and g that can be implemented by users for their types. In the package, f and g are empty generic functions, so MethodErrors will be thrown if they are not impl…

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## [\`Pkg.checkout\` clears \`REQUIRE\`](https://discourse.julialang.org/t/pkg-checkout-clears-require/935)

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**Author:** [@cortner](https://discourse.julialang.org/u/cortner)\
**Replies:** 4\
**Last updated:** [December 14, 2016, 7:44pm UTC](https://discourse.julialang.org/t/pkg-checkout-clears-require/935 "2016-12-14T19:44:08Z")

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??? julia\> Pkg.checkout("ModernGL") INFO: Checking out ModernGL master... INFO: Pulling ModernGL latest master... INFO: Removing ASTInterpreter v0.0.4 INFO: Removing AbstractTrees v0.0.4 INFO: Removing AppleAccelerate v…

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## [@static but do not parse the invalid branch](https://discourse.julialang.org/t/static-but-do-not-parse-the-invalid-branch/898)

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**Author:** [@tawheeler](https://discourse.julialang.org/u/tawheeler)\
**Replies:** 1\
**Last updated:** [December 12, 2016, 7:58pm UTC](https://discourse.julialang.org/t/static-but-do-not-parse-the-invalid-branch/898 "2016-12-12T19:58:14Z")

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We would like to make use of an 0.5 feature which fails to parse on 0.4 @static if Base.VERSION.major == 0 && Base.VERSION.minor \< 5 sN = sparsevec(sum(N\[1:ncategories\[i\],:\], 1)) # Slower, but should be suppor…

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## [Defining function calls on an object](https://discourse.julialang.org/t/defining-function-calls-on-an-object/873)

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**Author:** [@dpsanders](https://discourse.julialang.org/u/dpsanders)\
**Replies:** 3\
**Last updated:** [December 11, 2016, 11:36pm UTC](https://discourse.julialang.org/t/defining-function-calls-on-an-object/873 "2016-12-11T23:36:51Z")

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I am confused about how to define function call syntax for objects. If I have a concrete type then I can do it: type MyConcrete end (c::MyConcrete)(x) = "hello" julia\> cc = MyConcrete() MyConcrete() julia\> (c::MyCon…

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## [Pkg sends usage info to Google Analytics \[Update: No, it doesn't\]](https://discourse.julialang.org/t/pkg-sends-usage-info-to-google-analytics-update-no-it-doesnt/761)

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**Author:** [@mlhetland](https://discourse.julialang.org/u/mlhetland)\
**Replies:** 3\
**Last updated:** [December 6, 2016, 7:27pm UTC](https://discourse.julialang.org/t/pkg-sends-usage-info-to-google-analytics-update-no-it-doesnt/761 "2016-12-06T19:27:46Z")

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Just got the following message when running Pkg: Updating Homebrew... ==\> Homebrew has enabled anonymous aggregate user behaviour analytics. Read the analytics documentation (and how to opt-out) here: https://git.io/b…

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## [Is there a sortperm function in Python?](https://discourse.julialang.org/t/is-there-a-sortperm-function-in-python/590)

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**Author:** [@Alexei\_Serdiuk](https://discourse.julialang.org/u/Alexei_Serdiuk)\
**Replies:** 1\
**Last updated:** [November 26, 2016, 11:12pm UTC](https://discourse.julialang.org/t/is-there-a-sortperm-function-in-python/590 "2016-11-26T23:12:17Z")

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Hi! Please, help me to define the \> sortperm function in Python. I couldn’t find it by myself. Thanks.

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## [Julia font face at juliacomputing](https://discourse.julialang.org/t/julia-font-face-at-juliacomputing/126)

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**Author:** [@musm](https://discourse.julialang.org/u/musm)\
**Replies:** 4\
**Last updated:** [November 10, 2016, 4:33pm UTC](https://discourse.julialang.org/t/julia-font-face-at-juliacomputing/126 "2016-11-10T16:33:06Z")

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Julia font is inconsistent across the website and also inconsistent with the official julia logo font face

[Previous page](https://discourse.julialang.org/c/offtopic/29.md?no_subcategories=false&page=27)