Le mercredi 30 septembre 2015 à 10:31 -0700, Alex Ames a écrit : > Another downvote on linspace returning a range object. It seems odd > for linspace and logspace to return different types, and linrange > provides the low-memory option where needed. Numpy's `linspace` also > returns an array object. > I ran into errors when trying to plot a function over a linspace of > x values, since plotting libs currently expect vectors as arguments, > not range objects. Easily fixed if you know Julia well, but > Matlab/Python converts may be stymied. This sounds more like an issue with the plotting libraries. In most cases, you shouldn't care about the actual type of a read-only AbstractArray. If they only support the Array type, people will run into the same issue when using integer ranges à la 1:10 anyway.
Do you have other examples in which returning a range object is an issue? So far, that's the only one I've read (except for the confusion about deprecation warnings). Regards > On Wednesday, September 30, 2015 at 12:19:22 PM UTC-5, J Luis wrote: > > I want to add my voice to the dislikers. Those are the type of > > surprises that are not welcome mainly for matlab users. > > > > quarta-feira, 30 de Setembro de 2015 às 16:53:57 UTC+1, Christoph > > Ortner escreveu: > > > I also strongly dislike the `linspace` change; I like the idea > > > though of having `linspace` and `linrange`, where the former > > > should give the array. > > > Christoph > > > > > > > > > On Wednesday, 30 September 2015 10:21:36 UTC+1, Michele Zaffalon > > > wrote: > > > > I just realize that the thread is about 0.3.11 and I am showing > > > > output for 0.4.0-rc2. Sorry for the noise. > > > > > > > > On Wed, Sep 30, 2015 at 11:17 AM, Michele Zaffalon < > > > > michele....@gmail.com> wrote: > > > > > > > > > > On Wed, Sep 30, 2015 at 9:50 AM, Milan Bouchet-Valat < > > > > > nali...@club.fr> wrote: > > > > > > Le mercredi 30 septembre 2015 à 08:55 +0200, Michele > > > > > > Zaffalon a écrit : > > > > > > > Just curious: linspace returns a Range object, but > > > > > > logspace returns a > > > > > > > vector because there is no much use case for a LogRange > > > > > > object? > > > > > > > > > > > > > > @feza: I have also seen the deprecation warning going > > > > > > away after a > > > > > > > couple of calls, but I am not sure why. If you restart > > > > > > Julia, the > > > > > > > deprecations reappear. > > > > > > Deprecation warnings are only printed once for each call > > > > > > place. The > > > > > > idea is that once you're aware of it, there's no point in > > > > > > nagging you. > > > > > > > > > > > > Anyway, that warning is most probably not related to > > > > > > linspace at all, > > > > > > but rather to the array concatenation syntax resulting in > > > > > > an effect > > > > > > equivalent to collect(). If you show us a piece of code > > > > > > that prints the > > > > > > warning, we can give you more details. > > > > > > > > > > > > > > > > > > Regards > > > > > Sorry, you are right, I was referring to the concatenation. > > > > > It prints it exaclty twice if I type it in the REPL, it > > > > > always prints it if I define it within a function e.g. a() = > > > > > [1:3]. > > > > > > > > > > C:\Users\michele.zaffalon>julia > > > > > _ > > > > > _ _ _(_)_ | A fresh approach to technical > > > > > computing > > > > > (_) | (_) (_) | Documentation: > > > > > http://docs.julialang.org > > > > > _ _ _| |_ __ _ | Type "?help" for help. > > > > > | | | | | | |/ _` | | > > > > > | | |_| | | | (_| | | Version 0.4.0-rc2 (2015-09-18 17:51 > > > > > UTC) > > > > > _/ |\__'_|_|_|\__'_| | Official http://julialang.org/ rele > > > > > ase > > > > > |__/ | x86_64-w64-mingw32 > > > > > > > > > > julia> [1:3] > > > > > WARNING: [a] concatenation is deprecated; use collect(a) > > > > > instead > > > > > in depwarn at deprecated.jl:73 > > > > > in oldstyle_vcat_warning at abstractarray.jl:29 > > > > > in vect at abstractarray.jl:32 > > > > > while loading no file, in expression starting on line 0 > > > > > 3-element Array{Int64,1}: > > > > > 1 > > > > > 2 > > > > > 3 > > > > > > > > > > julia> [1:3] > > > > > WARNING: [a] concatenation is deprecated; use collect(a) > > > > > instead > > > > > in depwarn at deprecated.jl:73 > > > > > in oldstyle_vcat_warning at abstractarray.jl:29 > > > > > in vect at abstractarray.jl:32 > > > > > while loading no file, in expression starting on line 0 > > > > > 3-element Array{Int64,1}: > > > > > 1 > > > > > 2 > > > > > 3 > > > > > > > > > > julia> [1:3] > > > > > 3-element Array{Int64,1}: > > > > > 1 > > > > > 2 > > > > > 3 > > > > > > > > > > julia> a() = [1:3] > > > > > a (generic function with 1 method) > > > > > > > > > > julia> a() > > > > > WARNING: [a] concatenation is deprecated; use collect(a) > > > > > instead > > > > > in depwarn at deprecated.jl:73 > > > > > in oldstyle_vcat_warning at abstractarray.jl:29 > > > > > in a at none:1 > > > > > while loading no file, in expression starting on line 0 > > > > > 3-element Array{Int64,1}: > > > > > 1 > > > > > 2 > > > > > 3 > > > > > > > > > > julia> a() > > > > > WARNING: [a] concatenation is deprecated; use collect(a) > > > > > instead > > > > > in depwarn at deprecated.jl:73 > > > > > in oldstyle_vcat_warning at abstractarray.jl:29 > > > > > in a at none:1 > > > > > while loading no file, in expression starting on line 0 > > > > > 3-element Array{Int64,1}: > > > > > 1 > > > > > 2 > > > > > 3 > > > > > > > > > > julia> a() > > > > > WARNING: [a] concatenation is deprecated; use collect(a) > > > > > instead > > > > > in depwarn at deprecated.jl:73 > > > > > in oldstyle_vcat_warning at abstractarray.jl:29 > > > > > in a at none:1 > > > > > while loading no file, in expression starting on line 0 > > > > > 3-element Array{Int64,1}: > > > > > 1 > > > > > 2 > > > > > 3 > > > > > > > > > > > > > > > > > > On Wed, Sep 30, 2015 at 5:40 AM, feza <moham...@gmail.com > > > > > > > wrote: > > > > > > > > Strange it *was* giving me an error saying deprecated > > > > > > and that I > > > > > > > > should use collect, but now it's fine. > > > > > > > > > > > > > > > > > > > > > > > > On Tuesday, September 29, 2015 at 10:28:12 PM UTC-4, > > > > > > Sheehan Olver > > > > > > > > wrote: > > > > > > > > > fez, I'm pretty sure the code works fine without the > > > > > > collect: > > > > > > > > > when exp is called on linspace it converts it to a > > > > > > vector. > > > > > > > > > Though the returned t will be linspace object. > > > > > > > > > > > > > > > > > > On Wednesday, September 30, 2015 at 12:10:55 PM > > > > > > UTC+10, feza > > > > > > > > > wrote: > > > > > > > > > > Here's the code I was using where I needed to use > > > > > > collect (I've > > > > > > > > > > been playing around with Julia, so any suggestions > > > > > > on this code > > > > > > > > > > for perf is welcome ;) ) . In general linspace (or > > > > > > the : > > > > > > > > > > notation) is also used commonly to lay a grid in > > > > > > space for > > > > > > > > > > solving a PDE for some other use cases. > > > > > > > > > > > > > > > > > > > > function gp(n) > > > > > > > > > > n = convert(Int,n) > > > > > > > > > > t0 = 0 > > > > > > > > > > tf = 5 > > > > > > > > > > t = collect( linspace(t0, tf, n+1) ) > > > > > > > > > > sigma = exp( -(t - t[1]) ) > > > > > > > > > > > > > > > > > > > > c = [sigma; sigma[(end-1):-1:2]] > > > > > > > > > > lambda = fft(c) > > > > > > > > > > eta = sqrt(lambda./(2*n)) > > > > > > > > > > > > > > > > > > > > Z = randn(2*n) + im*randn(2*n) > > > > > > > > > > x = real( fft( Z.*eta ) ) > > > > > > > > > > return (x, t) > > > > > > > > > > end > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > On Tuesday, September 29, 2015 at 8:59:52 PM UTC-4, > > > > > > Stefan > > > > > > > > > > Karpinski wrote: > > > > > > > > > > > I'm curious why you need a vector rather than an > > > > > > object. Do > > > > > > > > > > > you mutate it after creating it? Having linspace > > > > > > return an > > > > > > > > > > > object instead of a vector was a bit of a unclear > > > > > > judgement > > > > > > > > > > > call so getting feedback would be good. > > > > > > > > > > > > > > > > > > > > > > On Tuesday, September 29, 2015, Patrick Kofod > > > > > > Mogensen < > > > > > > > > > > > patrick....@gmail.com> wrote: > > > > > > > > > > > > No: > > > > > > > > > > > > > > > > > > > > > > > > julia> logspace(0,3,5) > > > > > > > > > > > > 5-element Array{Float64,1}: > > > > > > > > > > > > 1.0 > > > > > > > > > > > > 5.62341 > > > > > > > > > > > > 31.6228 > > > > > > > > > > > > 177.828 > > > > > > > > > > > > 1000.0 > > > > > > > > > > > > > > > > > > > > > > > > On Tuesday, September 29, 2015 at 8:50:47 PM > > > > > > UTC-4, Luke > > > > > > > > > > > > Stagner wrote: > > > > > > > > > > > > > Thats interesting. Does logspace also return > > > > > > a range? > > > > > > > > > > > > > > > > > > > > > > > > > > On Tuesday, September 29, 2015 at 5:43:28 PM > > > > > > UTC-7, Chris > > > > > > > > > > > > > wrote: > > > > > > > > > > > > > > In 0.4 the linspace function returns a > > > > > > range object, > > > > > > > > > > > > > > and you need to use collect() to expand it. > > > > > > I'm also > > > > > > > > > > > > > > interested in nicer syntax. > > > > > > > > > > > > > > >
