On Wed, Sep 30, 2015 at 9:50 AM, Milan Bouchet-Valat <nalimi...@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/ release
|__/ | 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 <mohamad...@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.
>
