I have an algorithm where the bulk of the computation time is spent
calculating an operation of the form
Matrix .^ transpose(Vector)
I was able to get a 33% speed up by re-writing this as
exp(transpose(Vector) .* log(Matrix))
however this is something of a hack and I don't really approve of
://docs.julialang.org/en/release-0.4/stdlib/io-network/#Base.readdlm).
>
> Perhaps if the fields are quoted, the comment character does not have
> effect, but haven't checked this.
>
> On Saturday, June 25, 2016 at 4:41:55 PM UTC-4, Anonymous wrote:
>>
>> Let's say I have
Let's say I have a file of the form
1#hello
2hello
Where the space between the number and the ascii string is intended to be a
tab, then I run
my_file = readdlm(file, '\t')
this reads in the first line as "". Is this the desired functionality? It
works fine with other characters
So I've gotten about as much mileage out of print_with_color() as I can,
which is to say not much, it doesn't even print the right colors half the
time. There's a bunch of color packages which seem to be concerned with
abstractly manipulating different color parameterizations, but no mention
Kofod Mogensen <patrick@gmail.com
> > wrote:
> > But that is exactly what Forgy's code does
> >
> > expression && do_something
>
> Problem with this is that it is a bit cryptic.
>
> There is this related issue:
> https://github.com/Julia
I think maybe I didn't write exactly what I meant to. The expression in my
original post should have been a boolean value, I want to mimic an if
statement basically. Something of the form:
boolean ? expression_to_eval_if_boolean_is_true
Since the ternary operator mimics an if-else
So we have the ternary operator
expression ? eval_if_true : eval_if_false
You can jimmy-rig this into a binary operator by doing
expression ? eval_if_true : nothing
so why not have it be an optional binary operator by making the colon
optional, so that I could have
expression ? eval_if_true
it does appear to be related, unfortunately no resolution appears to be as
of yet forth coming.
On Sunday, June 5, 2016 at 6:53:56 PM UTC-7, Miguel Bazdresch wrote:
>
> This may be related: https://github.com/JuliaLang/julia/issues/16248
>
> On Sun, Jun 5, 2016 at 6:16 PM, An
So I have a BysteString vector A, containing a bunch of byte strings of
varying lengths of the form:
"1,2,\n"
"\n"
"5,2,4\n"
etc.
What I have set up is to do
[vec(readdlm(IOBuffer(line), ',', Float64)) for line in A]
However because as you see above the second line is empty except for the
. But still filing a
> bug report, if one does not exist yet, is probably the right thing to do.
>
> On Wed, 2016-06-01 at 03:26, Anonymous <esp...@gmail.com >
> wrote:
> > Consider the code:
> >
> > filter(n -> true, collect(1:0))
> >
> &
Consider the code:
filter(n -> true, collect(1:0))
this returns a 0-element array. However if I don't collect the iterator
into an array:
filter(n -> true, 1:0)
I get the error
Error: TypeError: typeassert: expected AbstractArray{Bool, N}, got
Array{Int64, 1} in filter at array.jl:923
It
from changing them in the future.
>
> On Friday, May 27, 2016 at 6:52:17 PM UTC-4, Anonymous wrote:
>>
>> Is there a way to have an alias to a field name? For instance suppose I
>> have
>>
>> type Foo
>> x::Int
>> end
>>
>> and I want to have Foo
Is there a way to have an alias to a field name? For instance suppose I
have
type Foo
x::Int
end
and I want to have Foo.y reference Foo.x, but I don't want an extra field y
in order to save memory. Of course why not just have
type Foo
y::Int
end
instead? Because I wan't the user to access
Wow strange, I could have sworn I tried that and it didn't do anything, but
now it works, thanks.
On Monday, May 16, 2016 at 1:40:06 AM UTC-7, David P. Sanders wrote:
>
> Change the print statement to print(io, "..."). io is the object of type
> IO that you need to print to.
So I have code of the form:
type Foo
x::Int
end
Base.show(io::IO, foo::Foo) = print("Foo:\n x = $(foo.x)")
This works fine for a single instance of Foo, but when I have an array of
Foo objects the display for the array in the REPL calls Base.show()
multiple times on each element and doesn't
Yes the algorithm I'm testing this on is fairly polished at this point, all
variables are within a type and they all have strict type declarations.
The memory allocations are very low compared to the vectorized code, so
memory-wise the loops are doing their job, but this doesn't translate into
ou run it twice? Remember that memory is allocated during JIT
> compilation, so the amount of memory on the first call is completely
> meaningless.
>
> --Tim
>
> On Wednesday, May 11, 2016 11:03:38 PM Anonymous wrote:
> > In response to both Kristoffer and Keno's timely res
So the consensus is not that Julia's devectorized code is so much faster
than its vectorized code (in fact I keep getting slow-downs when I test out
various devectorizations of my algorithms), but that R's devectorized code
just sucks.
On Thursday, May 12, 2016 at 4:49:42 AM UTC-7, Stefan
So I guess the consensus is not that Julia's devectorized code is so much
faster than its vectorized code (in fact I keep getting slow downs when I
test out different devectorizations of my algorithms), but that R's
devectorized code just sucks, either that or I really suck at writing for
Bouchet-Valat wrote:
>
> Le mercredi 11 mai 2016 à 23:03 -0700, Anonymous a écrit :
> > In response to both Kristoffer and Keno's timely responses,
> >
> > Originally I just did a simple @time test of the form
> > Matrix .* horizontal vector
> >
> > and
Accelerator.jl. They have a quite
> > sophisticated compiler that does loop fusions and parallelization and
> other
> > cool stuff.
> >
> >
> >
> > On Thursday, May 12, 2016 at 7:22:24 AM UTC+2, Anonymous wrote:
> >>
> >> This remains one of t
This remains one of the main drawbacks of Julia, and the devectorize
package is basically useless as it doesn't support some really crucial
vectorized operations. I'd really prefer not to rewrite all my vectorized
code into nested loops if at all possible, but I really need more speed,
can
Why are NaNs allowed to be created without raising an error, and then
allowed to propagate around your program corrupting basically all future
computation.
The question basically says it all, delete!(mydict, key), will delete a
single key, but how do I pass a vector of keys to delete! in order to
delete multiple keys at once?
edit of previous post:
I have color and year reversed, color should be ASCIIString and year should
be Int, same thing with Color and Year.
On Friday, April 15, 2016 at 12:56:16 AM UTC-7, Anonymous wrote:
>
> I need the fields color and year to be Int and ASCIIString, respectively,
&
the
constructor to return:
Car{Void, Void, Feature3, Void, Feature5, Feature6}(nothing, nothing, a,
nothing, b, c)
On Friday, April 15, 2016 at 12:18:56 AM UTC-7, Mauro wrote:
>
>
> On Fri, 2016-04-15 at 07:28, Anonymous <esp...@gmail.com >
> wrote:
> > OP here,
> >
>
OP here,
So it looks like the consensus is to use a single type with un-used
features set to nothing. I've actually been playing around with this
approach since I posted this question. Here's what I've got:
abstract AbstractCar
abstract Color
abstract Year
typealias ColorOrVoid
So I have a pretty complex problem in designing my type data structure
which I haven't been able to solve. Let's say I have an abstract car type:
abstract AbstractCar
now let's say I have the following possible features for a car:
color
horsepower
model
year
Now I want to be able to create
22:10 PM UTC-4, Anonymous wrote:
>>
>> Have the Julia developers considered the effects of setting
>> Base.min()=Inf and Base.max()=-Inf. This is common in real analysis since
>> it plays nice with set theory, i.e.
>>
>
> It only plays nicely with sets of
:23 PM UTC-7, Eric Forgy wrote:
>
> Hi Anonymous,
>
> One of the nice things about Julia is that if you want that feature in
> your code, you just need to do this:
>
> import Base: min, max
>
> min() = Inf
> max() = -Inf
>
> Voila. It will be a good/fast as
Have the Julia developers considered the effects of setting Base.min()=Inf
and Base.max()=-Inf. This is common in real analysis since it plays nice
with set theory, i.e.
A ⊆ B => max(A) ≤ max(B)
A ⊆ B => min(A) ≥ min(B)
Thus since the empty set ø is a subset of every set, the max of it
If I have a vector of data which I don't intend to ever change, should I
represent it as a tuple rather than a 1d array? Is there any benefit above
and beyond protecting against mutability? Is it more efficient?
> On Tuesday, April 5, 2016 at 1:12:00 PM UTC+2, Anonymous wrote:
>>
>> I couldn't really figure out a good way to describe it my title, but what
>> I'm trying to do is this:
>>
>> type Foo{T}
>> x::Vector{T}
>> end
>>
>> Foo{T}() = Foo
I couldn't really figure out a good way to describe it my title, but what
I'm trying to do is this:
type Foo{T}
x::Vector{T}
end
Foo{T}() = Foo{T}(T[])
but I get the warning msg: Warning: static parameter T does not occur in
signature for call at none:1. The method will not be callable.
How
oh cool that's convenient, for some reason the nzrange function isn't
mentioned in the documentation.
On Friday, April 1, 2016 at 2:46:53 AM UTC-7, Mauro wrote:
>
> On Fri, 2016-04-01 at 11:07, Anonymous <esp...@gmail.com >
> wrote:
> > but what if I need to a
s = sprand(10^7, 10^7, 1e-7);
>
> julia> @time rowvals(s);
> 0.04 seconds (4 allocations: 160 bytes)
>
> julia> @time colvals(s);
> 0.508060 seconds (20 allocations: 533.748 MB, 14.61% gc time)
>
>
> On Fri, 2016-04-01 at 10:48, Anonymous &
There is a rowals function, and then there is a find function, and the find
function actually allows you to write a one line colvals function:
colvals(S::SparseMatrixCSC) = round(Int, floor(find(S)/(size(S, 1)+0.1))+1)
shouldn't someone add this to base?
course.
>
> I'm sure you know this, but you'll want to access them through the return
> values of findnz or equivalent, not using S[i,j].
>
> --Tim
>
> On Monday, March 07, 2016 10:50:58 AM Anonymous wrote:
> > So I have a sparse matrix which doesn't get modified
So I have a sparse matrix which doesn't get modified by for which I would
like to access by rows, is there significantly more overhead in accessing
rows vs columns? If so, would it be more efficient to instead access the
columns of its transpose?
Is the following code considered bad form in Julia?
immutable Foo
func::Function
end
foo = Foo(x->x^2)
foo.func(3)
This mimics the behavior of OOP since just like in OOP the internal method
cannot be changed (since the type is immutable). Sometimes it really does
make the most sense to
wow that is crazy complicated
this is a good solution, although it prevents the user from defining their
own custom metric.
On Monday, January 18, 2016 at 9:33:05 AM UTC-8, Matt Bauman wrote:
>
> On Monday, January 18, 2016 at 11:54:49 AM UTC-5, Anonymous wrote:
>>
>> As you can see, I have to define a who
This came up as I was trying to define a sphere manifold type which can
have distinct metric structures put on it, here is how I have to do it in
Julia:
abstract Manifold
abstract Metric
immutable Metric1 <: Metric
end
immutable Metric2 <: Metric
end
immutable Sphere{T<:Metric} <: Manifold
The issue is that there is no cross section of metrics, one from each
manifold, which can all be grouped under the heading of RIEMANNIAN, same
with LORENTZIAN, etc. Each manifold will have its own set of idiosyncratic
metrics, and the user might require the functionality of being able to
horizonatally
I trust y'all will get this to the right people, where it can do some good.
to do? :-)
Cheers,
Kevin
On Tue, Jan 20, 2015 at 9:33 PM, Anonymous esp...@gmail.com javascript:
wrote:
horizonatally
I trust y'all will get this to the right people, where it can do some
good.
I'm trying to figure out how to create an alias/shortcut whatever in the
mac terminal so that I can just type julia and julia will start up, just
the way python works when I type python. It's something about a bash or
something.
if A is a multidimensional array and t a tuple, and I try to do something
of the form A[*t], I get an error, yet if I put the tuple in manually, for
instance A[*(1,1)], it works.
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