# Latest

**URL:** https://discourse.julialang.org/latest.md?page=1808

[Latest](https://discourse.julialang.org/latest.md) · [Categories](https://discourse.julialang.org/categories.md) · [Tags](https://discourse.julialang.org/tags.md)

**Page:** 1809

---

## [Guidance on profiling / benchmarking I/O opperations on sparse dataset](https://discourse.julialang.org/t/guidance-on-profiling-benchmarking-i-o-opperations-on-sparse-dataset/35483)

<div class="topic-metadata">

**Author:** [@kevbonham](https://discourse.julialang.org/u/kevbonham)\
**Replies:** 11\
**Last updated:** [March 5, 2020, 2:12pm UTC](https://discourse.julialang.org/t/guidance-on-profiling-benchmarking-i-o-opperations-on-sparse-dataset/35483 "2020-03-05T14:12:20Z")

</div>

I have a specific data reading problem that I’m trying to improve. I’m not sure if the details are important or not, but here’s the gist: I have some number (high hundreds to low thousands) of indiviudual CSV files. Ea…

---

## [Calling type-unstable functions within a type-stable function (and usage of Val)](https://discourse.julialang.org/t/calling-type-unstable-functions-within-a-type-stable-function-and-usage-of-val/35572)

<div class="topic-metadata">

**Author:** [@e3c6](https://discourse.julialang.org/u/e3c6)\
**Replies:** 0\
**Last updated:** [March 5, 2020, 12:22pm UTC](https://discourse.julialang.org/t/calling-type-unstable-functions-within-a-type-stable-function-and-usage-of-val/35572 "2020-03-05T12:22:07Z")

</div>

I have a function f that is potentially type-unstable. I also have a function g that in the end is type-stable, but inside it calls f. Here is an (artificial) example, implemented in different ways: f1(t::Tuple, i::Int…

---

## [Broadcast macro "breaks" norm](https://discourse.julialang.org/t/broadcast-macro-breaks-norm/35570)

<div class="topic-metadata">

**Author:** [@cshen](https://discourse.julialang.org/u/cshen)\
**Replies:** 1\
**Last updated:** [March 5, 2020, 11:51am UTC](https://discourse.julialang.org/t/broadcast-macro-breaks-norm/35570 "2020-03-05T11:51:02Z")

</div>

Hello, I found this rather interesting behaviour julia\> using LinearAlgebra julia\> a = \[0, 0, 1\] 3-element Array{Int64,1}: 0 0 1 julia\> @. a/norm(a) 3-element Array{Float64,1}: NaN NaN 1.0 julia\> a./norm(…

---

## [Subs for Matrices in SymEngine](https://discourse.julialang.org/t/subs-for-matrices-in-symengine/35566)

<div class="topic-metadata">

**Author:** [@rajesh](https://discourse.julialang.org/u/rajesh)\
**Replies:** 2\
**Last updated:** [March 5, 2020, 11:47am UTC](https://discourse.julialang.org/t/subs-for-matrices-in-symengine/35566 "2020-03-05T11:47:27Z")

</div>

Hi, I am using SymEngine but unable to substitute values when the symbols are in a matrix. My code is as follows: a,b,c = symbols(“a b c”) e1 = Array{Symbol,1} e1 = \[a^2, b^2, c^2\] e2 = subs(e1, a=\>2, b=\>1, c=\>3) T…

---

## [Bounds on package versions](https://discourse.julialang.org/t/bounds-on-package-versions/35511)

<div class="topic-metadata">

**Author:** [@bkamins](https://discourse.julialang.org/u/bkamins)\
**Replies:** 10\
**Last updated:** [March 5, 2020, 11:46am UTC](https://discourse.julialang.org/t/bounds-on-package-versions/35511 "2020-03-05T11:46:50Z")

</div>

Given the discussion on DataFrames.jl tagging/dependencies cycle we recently had on Slack I have the following general question. Currently Pkg manager is strict with respect to ensuring consistency of versions of depend…

---

## [Bug in CSV.read?](https://discourse.julialang.org/t/bug-in-csv-read/35562)

<div class="topic-metadata">

**Author:** [@BLI](https://discourse.julialang.org/u/BLI)\
**Replies:** 7\
**Last updated:** [March 5, 2020, 9:53am UTC](https://discourse.julialang.org/t/bug-in-csv-read/35562 "2020-03-05T09:53:45Z")

</div>

I’m trying to represent infinity in Excel, and have tried with 1e18 and 1e19 (since I haven’t found an Inf symbol). I then export this to a CSV file, and upon checking the resulting file in Notepad++, the numbers are rep…

---

## [Packages that contain \`Manifest.toml\` files](https://discourse.julialang.org/t/packages-that-contain-manifest-toml-files/35534)

<div class="topic-metadata">

**Author:** [@dmbates](https://discourse.julialang.org/u/dmbates)\
**Replies:** 2\
**Last updated:** [March 5, 2020, 9:50am UTC](https://discourse.julialang.org/t/packages-that-contain-manifest-toml-files/35534 "2020-03-05T09:50:52Z")

</div>

I have noticed that some of the packages I have installed contain Manifest.toml files. These include LLVM, FlatBuffers, and GPUArrays. Is this intentional? I thought a Manifest.toml file was to be removed from a pack…

---

## [IsApprox.jl uniform interface for approximate and exact equality](https://discourse.julialang.org/t/isapprox-jl-uniform-interface-for-approximate-and-exact-equality/35551)

<div class="topic-metadata">

**Author:** [@jlapeyre](https://discourse.julialang.org/u/jlapeyre)\
**Replies:** 1\
**Last updated:** [March 5, 2020, 9:44am UTC](https://discourse.julialang.org/t/isapprox-jl-uniform-interface-for-approximate-and-exact-equality/35551 "2020-03-05T09:44:47Z")

</div>

Sometimes I see an algorithm for a predicate duplicated because the notion of closeness varies. Eg. exact equality, (maximum over) elementwise distance, closeness in norm. This package is a quick initial attempt at addr…

---

## [What is the difference between \`Threads.@spawn\` and \`Distributed.@spawnnat\`](https://discourse.julialang.org/t/what-is-the-difference-between-threads-spawn-and-distributed-spawnnat/35560)

<div class="topic-metadata">

**Author:** [@schlichtanders](https://discourse.julialang.org/u/schlichtanders)\
**Replies:** 3\
**Last updated:** [March 5, 2020, 9:37am UTC](https://discourse.julialang.org/t/what-is-the-difference-between-threads-spawn-and-distributed-spawnnat/35560 "2020-03-05T09:37:40Z")

</div>

trying to get a better understanding on Julia’s parallelization possibilities I heard about the awesome @spawn macro which is new in Julia 1.3 Looking more into the available tools I am confused about the difference bet…

---

## [Difference between @time in Julia 1.3.1 and Julia 1.4.0-rc2](https://discourse.julialang.org/t/difference-between-time-in-julia-1-3-1-and-julia-1-4-0-rc2/35422)

<div class="topic-metadata">

**Author:** [@f-fathurrahman](https://discourse.julialang.org/u/f-fathurrahman)\
**Replies:** 10\
**Last updated:** [March 5, 2020, 9:26am UTC](https://discourse.julialang.org/t/difference-between-time-in-julia-1-3-1-and-julia-1-4-0-rc2/35422 "2020-03-05T09:26:51Z")

</div>

Dear all, While I was testing Julia 1.4.0-rc2 for my package I notice very different results of @time compared with Julia 1.3.0. (I am sorry that I cannot provide an MWE for this.) The code basically trying to run a “…

---

## [Conda cannot be added on Julia 1.3.1 Win10, local user install](https://discourse.julialang.org/t/conda-cannot-be-added-on-julia-1-3-1-win10-local-user-install/35561)

<div class="topic-metadata">

**Author:** [@vinnief](https://discourse.julialang.org/u/vinnief)\
**Replies:** 0\
**Last updated:** [March 5, 2020, 8:40am UTC](https://discourse.julialang.org/t/conda-cannot-be-added-on-julia-1-3-1-win10-local-user-install/35561 "2020-03-05T08:40:14Z")

</div>

After Installing Julia 1.3.1 on Win10, (as local user), Conda won’t build, it throws the error Error building Conda : │ ERROR: LoadError: SystemError (with C:\\Users\\julia): mkdir: Permission denied if I try import Co…

---

## [Julia v1.3.1 has been released](https://discourse.julialang.org/t/julia-v1-3-1-has-been-released/32813)

<div class="topic-metadata">

**Author:** [@ararslan](https://discourse.julialang.org/u/ararslan)\
**Replies:** 22\
**Last updated:** [March 5, 2020, 8:28am UTC](https://discourse.julialang.org/t/julia-v1-3-1-has-been-released/32813 "2020-03-05T08:28:22Z")

</div>

Julia version 1.3.1, the first patch release in the 1.3 series of releases, is now available. You can get binaries for Linux (i686, x86-64, AArch64, ARMv7), FreeBSD (x86-64), macOS, and Windows (32-, 64-bit) at Download …

---

## [Why can't I put a anonymous function inside a type parameter of a struct?](https://discourse.julialang.org/t/why-cant-i-put-a-anonymous-function-inside-a-type-parameter-of-a-struct/35555)

<div class="topic-metadata">

**Author:** [@Qiyamah](https://discourse.julialang.org/u/Qiyamah)\
**Replies:** 2\
**Last updated:** [March 5, 2020, 7:40am UTC](https://discourse.julialang.org/t/why-cant-i-put-a-anonymous-function-inside-a-type-parameter-of-a-struct/35555 "2020-03-05T07:40:16Z")

</div>

abstract type FieldName{A} end abstract type FieldType{A} end abstract type FieldValue{A} end abstract type FieldMutability{A} end abstract type Field{A\<:FieldName, B\<:FieldType, C\<:FieldValue, D\<:…

---

## [How do I configure .travis.yml to run julia with depwarn=no (and another question)](https://discourse.julialang.org/t/how-do-i-configure-travis-yml-to-run-julia-with-depwarn-no-and-another-question/35558)

<div class="topic-metadata">

**Author:** [@anon94023334](https://discourse.julialang.org/u/anon94023334)\
**Replies:** 2\
**Last updated:** [March 5, 2020, 7:31am UTC](https://discourse.julialang.org/t/how-do-i-configure-travis-yml-to-run-julia-with-depwarn-no-and-another-question/35558 "2020-03-05T07:31:01Z")

</div>

my current .travis.yml: language: julia os: - linux # - osx julia: - 1.3 - nightly notifications: email: false jobs: allow\_failures: - julia: nightly include: - stage: "Documentation" julia: …

---

## [Tags created by TagBot are not reachable](https://discourse.julialang.org/t/tags-created-by-tagbot-are-not-reachable/35544)

<div class="topic-metadata">

**Author:** [@heliosdrm](https://discourse.julialang.org/u/heliosdrm)\
**Replies:** 5\
**Last updated:** [March 5, 2020, 7:03am UTC](https://discourse.julialang.org/t/tags-created-by-tagbot-are-not-reachable/35544 "2020-03-05T07:03:12Z")

</div>

The tags created by the new TagBot (as GitHub actions) cannot be reached from the commits they point at. E.g. git describe does not show those tags (it does show those created by the older TagBot app, though). I found t…

---

## [Transform \`Tuple{Union, NonUnion, Union, ...}\` to \`Union{Tuple{NonUnion, NonUnion, NonUnion, ...}, ...}\`](https://discourse.julialang.org/t/transform-tuple-union-nonunion-union-to-union-tuple-nonunion-nonunion-nonunion/35452)

<div class="topic-metadata">

**Author:** [@schlichtanders](https://discourse.julialang.org/u/schlichtanders)\
**Replies:** 4\
**Last updated:** [March 5, 2020, 6:53am UTC](https://discourse.julialang.org/t/transform-tuple-union-nonunion-union-to-union-tuple-nonunion-nonunion-nonunion/35452 "2020-03-05T06:53:18Z")

</div>

Hi all, does there exist a function which can transform a tuple type of the schema Tuple{Union, NonUnion, Union, ...}, i.e. with Union types on the first level, such that the Union goes out and we have Union{Tuple{NonUn…

---

## [\[ANN\] Traceur.jl: Make Your Julia Code Not Totally Slow](https://discourse.julialang.org/t/ann-traceur-jl-make-your-julia-code-not-totally-slow/9469)

<div class="topic-metadata">

**Author:** [@MikeInnes](https://discourse.julialang.org/u/MikeInnes)\
**Replies:** 20\
**Last updated:** [March 5, 2020, 6:51am UTC](https://discourse.julialang.org/t/ann-traceur-jl-make-your-julia-code-not-totally-slow/9469 "2020-03-05T06:51:51Z")

</div>

If, like me, you’re too lazy to learn to read @code\_typed, or all of the performance gotchas in the manual, you might find Traceur.jl interesting. It’s extremely simple to use: you throw your function at it, it yells at …

---

## [How can I solve stack over flow error while using Turing?](https://discourse.julialang.org/t/how-can-i-solve-stack-over-flow-error-while-using-turing/35552)

<div class="topic-metadata">

**Author:** [@Manu\_Francis](https://discourse.julialang.org/u/Manu_Francis)\
**Replies:** 2\
**Last updated:** [March 5, 2020, 4:24am UTC](https://discourse.julialang.org/t/how-can-i-solve-stack-over-flow-error-while-using-turing/35552 "2020-03-05T04:24:42Z")

</div>

Hi, I am trying to use Turing package with :reverse\_diff as AD background. In my program, the variable size is very high and the program looks similar as follows: @model test\_prob(y, M, N, K, ::Type{T}=Float64) where {…

---

## [Weight files from python called in Julia](https://discourse.julialang.org/t/weight-files-from-python-called-in-julia/35554)

<div class="topic-metadata">

**Author:** [@Atheesh\_M\_J](https://discourse.julialang.org/u/Atheesh_M_J)\
**Replies:** 0\
**Last updated:** [March 5, 2020, 4:11am UTC](https://discourse.julialang.org/t/weight-files-from-python-called-in-julia/35554 "2020-03-05T04:11:02Z")

</div>

I am new to Julia programing language. I had trained a binary classifier in python using tensorflow. I would like to know whether this weight file which was obtained by training in python can be used as it is(i.e., witho…

---

## [Looking for a script that runs the same code with different set of parameters and saves the results in different folders](https://discourse.julialang.org/t/looking-for-a-script-that-runs-the-same-code-with-different-set-of-parameters-and-saves-the-results-in-different-folders/35437)

<div class="topic-metadata">

**Author:** [@Ujku\_KU](https://discourse.julialang.org/u/Ujku_KU)\
**Replies:** 7\
**Last updated:** [March 5, 2020, 1:38am UTC](https://discourse.julialang.org/t/looking-for-a-script-that-runs-the-same-code-with-different-set-of-parameters-and-saves-the-results-in-different-folders/35437 "2020-03-05T01:38:41Z")

</div>

Hi guys, I am running a set of experiments and each of experiment differs from the rest by the set of the parameters which are picked by the same pool of parameters. I would like to run the experiments in a loop automati…

---

## [Optimization of time-dependent parameters with time-series in chemical model](https://discourse.julialang.org/t/optimization-of-time-dependent-parameters-with-time-series-in-chemical-model/35550)

<div class="topic-metadata">

**Author:** [@Newton-Climate](https://discourse.julialang.org/u/Newton-Climate)\
**Replies:** 0\
**Last updated:** [March 5, 2020, 1:35am UTC](https://discourse.julialang.org/t/optimization-of-time-dependent-parameters-with-time-series-in-chemical-model/35550 "2020-03-05T01:35:14Z")

</div>

Hello All, I have a coupled set of differential equations with some-time-dependent parameters that I would like to optimize. In the code at the bottom of this post, the k\_i terms are fixed kinetic constants, the c\[inde…

---

## [System of Two Differential equations](https://discourse.julialang.org/t/system-of-two-differential-equations/35535)

<div class="topic-metadata">

**Author:** [@erlebach](https://discourse.julialang.org/u/erlebach)\
**Replies:** 4\
**Last updated:** [March 5, 2020, 1:07am UTC](https://discourse.julialang.org/t/system-of-two-differential-equations/35535 "2020-03-05T01:07:33Z")

</div>

I am trying to implement a system of two ODEs. The following works: function diffusion!(du, u, p, t) α, β = p c, ce = u du\[1\] = -αc du\[2\] = -βce du = \[dc, dce\] end u0 = \[3.0, 7.0\] tspan = (0., 2.) p = \[1.0, 1…

---

## [Optical character recognition using JUlia](https://discourse.julialang.org/t/optical-character-recognition-using-julia/35218)

<div class="topic-metadata">

**Author:** [@Eldho.Ashna](https://discourse.julialang.org/u/Eldho.Ashna)\
**Replies:** 1\
**Last updated:** [March 5, 2020, 12:21am UTC](https://discourse.julialang.org/t/optical-character-recognition-using-julia/35218 "2020-03-05T00:21:16Z")

</div>

Hi all, I am new to julia programming language and would like to do optical character recognition using Julia. I know that there are different libraries for machine learning such as Flux, KNet, Tensorflow,jl etc. Can so…

---

## [Zoomable and pannable plots (in a separate window)? (Atom/MacOS)](https://discourse.julialang.org/t/zoomable-and-pannable-plots-in-a-separate-window-atom-macos/34352)

<div class="topic-metadata">

**Author:** [@Jandyman](https://discourse.julialang.org/u/Jandyman)\
**Replies:** 20\
**Last updated:** [March 5, 2020, 12:17am UTC](https://discourse.julialang.org/t/zoomable-and-pannable-plots-in-a-separate-window-atom-macos/34352 "2020-03-05T00:17:05Z")

</div>

I’m new to Julia / Atom / Juno. I’m excited about the possibilities, being an ex LISPer. Although something is a bit slow (Atom, JIT compilation?), it’s a pretty good user experience. The Juno debugger seems very well de…

---

## [Symbols in Gadfly Plots](https://discourse.julialang.org/t/symbols-in-gadfly-plots/35430)

<div class="topic-metadata">

**Author:** [@alphasig329](https://discourse.julialang.org/u/alphasig329)\
**Replies:** 2\
**Last updated:** [March 4, 2020, 11:19pm UTC](https://discourse.julialang.org/t/symbols-in-gadfly-plots/35430 "2020-03-04T23:19:39Z")

</div>

I am trying to incorporate some symbols in my xtick labels, but I have failed in using LaTeXStrings and unicode characters. I keep getting the following error: MethodError: Cannot \`convert\` an object of type Char to an …

---

## [Reading package dictionary & weaving jmd files](https://discourse.julialang.org/t/reading-package-dictionary-weaving-jmd-files/35469)

<div class="topic-metadata">

**Author:** [@kubasevca](https://discourse.julialang.org/u/kubasevca)\
**Replies:** 2\
**Last updated:** [March 4, 2020, 9:30pm UTC](https://discourse.julialang.org/t/reading-package-dictionary-weaving-jmd-files/35469 "2020-03-04T21:30:21Z")

</div>

Hello, I am new in Julia and I decided to use VS code as my IDE for Julia. I tried to follow youtube video JuliaCon 2018 | Visual Studio Code Julia extension | David Anthoff - YouTube to learn about Julia extension for …

---

## [Bug, adding Traceur? In a package or Julia? "undefined symbol: mbedtls\_x509\_crt ..."](https://discourse.julialang.org/t/bug-adding-traceur-in-a-package-or-julia-undefined-symbol-mbedtls-x509-crt/35536)

<div class="topic-metadata">

**Author:** [@Palli](https://discourse.julialang.org/u/Palli)\
**Replies:** 0\
**Last updated:** [March 4, 2020, 8:36pm UTC](https://discourse.julialang.org/t/bug-adding-traceur-in-a-package-or-julia-undefined-symbol-mbedtls-x509-crt/35536 "2020-03-04T20:36:16Z")

</div>

(v1.3) pkg\> add Traceur Updating registry at \`~/.julia/registries/General\` Updating git-repo \`https://github.com/JuliaRegistries/General.git\` /home/pharaldsson\_sym/julia-1.3.1/bin/julia: symbol lookup error: /home/ph…

---

## [CUDAnative dynamic allocation](https://discourse.julialang.org/t/cudanative-dynamic-allocation/35435)

<div class="topic-metadata">

**Author:** [@Michael\_Benton](https://discourse.julialang.org/u/Michael_Benton)\
**Replies:** 5\
**Last updated:** [March 4, 2020, 6:29pm UTC](https://discourse.julialang.org/t/cudanative-dynamic-allocation/35435 "2020-03-04T18:29:52Z")

</div>

I need to be able to dynamically allocate in kernel. val = MArray{Tuple{4}, Float32}(undef) is a way to get static allocation with StaticArrays.jl inside a CUDA kernel I figured something like Array{Float32}(undef, 4) …

---

## [uniformScaling non identity matrices](https://discourse.julialang.org/t/uniformscaling-non-identity-matrices/35532)

<div class="topic-metadata">

**Author:** [@hros](https://discourse.julialang.org/u/hros)\
**Replies:** 2\
**Last updated:** [March 4, 2020, 6:29pm UTC](https://discourse.julialang.org/t/uniformscaling-non-identity-matrices/35532 "2020-03-04T18:29:57Z")

</div>

How do I create efficient representations like the uniformScaling type for non identity matrices? for example how would I create the matrices X=\[0 1;1 0\] Z=\[1 0;0 -1\] as well as \[1 0;0 0\] and \[0 0;0 1\] with similar …

---

## [Clarification on the differences between \`Ptr\` and \`Ref\`](https://discourse.julialang.org/t/clarification-on-the-differences-between-ptr-and-ref/35531)

<div class="topic-metadata">

**Author:** [@kdheepak](https://discourse.julialang.org/u/kdheepak)\
**Replies:** 1\
**Last updated:** [March 4, 2020, 6:14pm UTC](https://discourse.julialang.org/t/clarification-on-the-differences-between-ptr-and-ref/35531 "2020-03-04T18:14:28Z")

</div>

I have a question regarding ccall, Ptr, Ref and pointer\_to\_objref. Let’s say I have a function that is like so mutable struct UserData x::Int end function foo(bar, userdata, err) ccall((:foo, liblibrary), Cvoi…

[Previous page](https://discourse.julialang.org/latest.md?page=1807)

[Next page](https://discourse.julialang.org/latest.md?page=1809)