Re: [julia-users] ANN: Docile Lexicon update.
Yes, the help system in 0.4 does search package documentation as well. — Mike On Sunday, 1 February 2015 03:32:26 UTC+2, i.cos...@me.com wrote: Ok, will Lexicon be baked into 0.4? If so, then the instructions in the latest documentation makes sense: http://docs.julialang.org/en/latest/manual/documentation/ Otherwise, there will need to be an extra line in the Accessing Documentation section. Cheers On Sunday, 1 February 2015 10:09:34 UTC+11, Michael Hatherly wrote: Make sure you’ve installed Lexicon as Tom has mentioned. Also call using Lexicon prior to trying to search for package docs at the REPL. — Mike On Saturday, 31 January 2015 22:57:36 UTC+2, i.cos...@me.com wrote: I installed Sims and ran `?sim` at REPL. I got the following back: `dasslsim (generic function with 20 methods)`. I see that there is an extensive docstring against sim in src/sim.jl. Why am I not seeing this at REPL? I'm on julia 0.3.5 On Thursday, 22 January 2015 03:54:14 UTC+11, Ivan Ogasawara wrote: great! El 21/01/2015 14:22, Michael Hatherly michael...@gmail.com escribió: Hi all, I’m pleased to announce the latest update to the Docile https://github.com/MichaelHatherly/Docile.jl and Lexicon https://github.com/MichaelHatherly/Lexicon.jl documentation packages. New features include: - Docile now supports plain strings http://michaelhatherly.github.io/Docile.jl/syntax/#plain-strings, ie. without @doc, as docstrings. Compatibility with the Julia 0.4 doc system is still present. - Thanks to Tom Short, Lexicon can now output nicely formatted markdown. This can then be used to create static documentation using programs such as MkDocs http://www.mkdocs.org/. See the documentation from the following packages for examples of the results: Sims https://tshort.github.io/Sims.jl/, Docile http://michaelhatherly.github.io/Docile.jl/, and Lexicon http://michaelhatherly.github.io/Lexicon.jl/. Any bugs or feature requests can be opened in either the Docile or Lexicon repos. Happy documenting! — Mike
[julia-users] Re: Robust Inner Products
If you wanted to implement such an algorithm, you would need to robust-ify the multiplication as well, using a two-product style algorithm: this paper goes into a lot of detail: http://www.ti3.tu-harburg.de/paper/rump/OgRuOi05.pdf Alternatively, you could use full double-double arithmetic: see https://github.com/simonbyrne/DoubleDouble.jl Simon On Sunday, 1 February 2015 11:37:13 UTC, Christoph Ortner wrote: I was delighted to find that Julia has robust summation algorithms implemented in Base. In my code I also need robust inner product. Is that implemented as well? I couldn't find it, but it is easy to write for myself (trivially sum_kbn(x.*y), but this allocates extra memory) But are there other similar summation-type algorithms that could benefit, and is there any interest in this? Christoph
[julia-users] Data structure with variable length outputs
Hi all- I am trying to figure out a graceful way to store output from a model simulation. Each simulated trial produces a single reaction time, a single choice and a vector of visual fixations generated by a Markov chain. The complicating factor is that the size of the vector of visual fixations varies on each simulated trial and I would like to generate multiple simulated trials. Is there a way to store these outputs in a data structure that will be easy to access in other functions? A related issue is the dynamic nature of the vector size. I am currently using vcat to add new values to the vector. Is there a more efficient method? Thank you in advance for your help.
[julia-users] create a multi data type structure in Julia
Hi all,
I'm a new Julia user and I'm starting to write a high-level multi data type
fits file reader and writer akin to IDL's mwrfits/mrdfits. I got most of
the dynamics figured out by I can't quite make a custom structure. For
example, I would like something like:
element = {name::string, lambda::[float_array, 5000 elements],
flux::[float_array, 5000 elements]}
structure = replicate(element, 500)
where structure inherits the members of element and can be called,
structure[1].name = the name of element 1
strucutre[1].lambda[1] = the first lambda element of the first structure
Thanks !!!
[julia-users] select! with range creating a memory allocation
I realize this is a more developer issue, but I'm wondering if anyone else thinks it would be a good idea for select! to be changed to not return A[r] (which allocates memory). I think it could return (A[r.start], A[r.stop]), sub(A, r) or even nothing. As it stands it seems like a performance penalty that can be avoided since the rest of the function should operate on memory in place. In my own project I've made a local copy of select for this reason and taken out the return value.
Re: [julia-users] create a multi data type structure in Julia
Have you seen
https://github.com/JuliaAstro/FITSIO.jl
Off-topic, but it would be awesome to have FITS integrated into Images.jl. I
could help with the integration, but it is pretty well documented:
https://github.com/timholy/Images.jl/blob/master/doc/extendingIO.md
Further discussion could happen at
https://github.com/JuliaAstro/FITSIO.jl/issues/18
--Tim
On Sunday, February 01, 2015 12:35:53 AM alex codoreanu wrote:
Hi all,
I'm a new Julia user and I'm starting to write a high-level multi data type
fits file reader and writer akin to IDL's mwrfits/mrdfits. I got most of
the dynamics figured out by I can't quite make a custom structure. For
example, I would like something like:
element = {name::string, lambda::[float_array, 5000 elements],
flux::[float_array, 5000 elements]}
structure = replicate(element, 500)
where structure inherits the members of element and can be called,
structure[1].name = the name of element 1
strucutre[1].lambda[1] = the first lambda element of the first structure
Thanks !!!
Re: [julia-users] Markdown Strings as Messages
This is something I've been thinking about as well, and overloading `print` etc. to work with markdown is definitely doable. I'm not sure how it would work in IJulia, but it would definitely be ok in the terminal. Use md unless you're writing inline docs (you might have to do a using Base.Markdown first). At the moment both are interchangeable but the idea is that doc needs to treat e.g. relative image and link paths specially, and may potentially also add things like reference syntax. On 1 February 2015 at 11:22, Christoph Ortner christophortn...@gmail.com wrote: I've tried (but failed), with Julia 0.4, to use Markdown strings doc . . . as messages, e.g., error messages or just to make some complex program output more readable. If, in a REPL or IJulia, I just write docblah `code` bleh in a single line, then this shows ok. But of course in a function or script, it will just generate an object of type `Base.Markdown.MD`, without output. [1] Question: how can I actually send it to the output, correctly formatted? [2] Suggestion: could `print`, `println`, `error` etc automatically interpret markdown strings and output them accordingly? [3] Question: why doc . . . and not md . . . ? Could these at least be used synonymously? Thanks, Christoph
Re: [julia-users] create a multi data type structure in Julia
Thanks Milan,
I defined Element as you suggested and created
*data=(Element, 2)*
but
*julia **data[1].lambda=[1., 2.0]*
*ERROR: type DataType has no field lambda*
Now that I have the structure data how do I access the branch members?
On Sunday, February 1, 2015 at 8:07:51 PM UTC+11, Milan Bouchet-Valat wrote:
Le dimanche 01 février 2015 à 00:35 -0800, alex codoreanu a écrit :
Hi all,
I'm a new Julia user and I'm starting to write a high-level multi data
type fits file reader and writer akin to IDL's mwrfits/mrdfits. I got
most of the dynamics figured out by I can't quite make a custom
structure. For example, I would like something like:
element = {name::string, lambda::[float_array, 5000 elements],
flux::[float_array, 5000 elements]}
structure = replicate(element, 500)
where structure inherits the members of element and can be called,
structure[1].name = the name of element 1
strucutre[1].lambda[1] = the first lambda element of the first
structure
Looks like a composite type would work:
type Element
name::UTF8String
lambda::Vector{Float64}
flux::Vector{Float64}
end
Regards
Re: [julia-users] create a multi data type structure in Julia
Le dimanche 01 février 2015 à 01:24 -0800, alex codoreanu a écrit :
Thanks Milan,
I defined Element as you suggested and created
data=(Element, 2)
What is this line supposed to do? All it does now is assign a tuple
containing the Element type, and the integer value 2.
If you want to create an Element instance, you should do e.g.:
element = Element(a name, [1, 2], [2, 3])
and then to create a list holding two Elements, and fill the first value
with the just created element:
data = Vector(Element, 2)
data[1] = element
Accessing members:
data[1].lambda
Regards
but
julia data[1].lambda=[1., 2.0]
ERROR: type DataType has no field lambda
Now that I have the structure data how do I access the branch members?
On Sunday, February 1, 2015 at 8:07:51 PM UTC+11, Milan Bouchet-Valat
wrote:
Le dimanche 01 février 2015 à 00:35 -0800, alex codoreanu a
écrit :
Hi all,
I'm a new Julia user and I'm starting to write a high-level
multi data
type fits file reader and writer akin to IDL's
mwrfits/mrdfits. I got
most of the dynamics figured out by I can't quite make a
custom
structure. For example, I would like something like:
element = {name::string, lambda::[float_array, 5000
elements],
flux::[float_array, 5000 elements]}
structure = replicate(element, 500)
where structure inherits the members of element and can be
called,
structure[1].name = the name of element 1
strucutre[1].lambda[1] = the first lambda element of the
first
structure
Looks like a composite type would work:
type Element
name::UTF8String
lambda::Vector{Float64}
flux::Vector{Float64}
end
Regards
[julia-users] Markdown Strings as Messages
I've tried (but failed), with Julia 0.4, to use Markdown strings doc . . . as messages, e.g., error messages or just to make some complex program output more readable. If, in a REPL or IJulia, I just write docblah `code` bleh in a single line, then this shows ok. But of course in a function or script, it will just generate an object of type `Base.Markdown.MD`, without output. [1] Question: how can I actually send it to the output, correctly formatted? [2] Suggestion: could `print`, `println`, `error` etc automatically interpret markdown strings and output them accordingly? [3] Question: why doc . . . and not md . . . ? Could these at least be used synonymously? Thanks, Christoph
[julia-users] Robust Inner Products
I was delighted to find that Julia has robust summation algorithms implemented in Base. In my code I also need robust inner product. Is that implemented as well? I couldn't find it, but it is easy to write for myself (trivially sum_kbn(x.*y), but this allocates extra memory) But are there other similar summation-type algorithms that could benefit, and is there any interest in this? Christoph
Re: [julia-users] create a multi data type structure in Julia
That worked but I had to use:
data = Array(Element, 2)
Thanks for the info!
On Sunday, February 1, 2015 at 8:57:23 PM UTC+11, Milan Bouchet-Valat wrote:
Le dimanche 01 février 2015 à 01:24 -0800, alex codoreanu a écrit :
Thanks Milan,
I defined Element as you suggested and created
data=(Element, 2)
What is this line supposed to do? All it does now is assign a tuple
containing the Element type, and the integer value 2.
If you want to create an Element instance, you should do e.g.:
element = Element(a name, [1, 2], [2, 3])
and then to create a list holding two Elements, and fill the first value
with the just created element:
data = Vector(Element, 2)
data[1] = element
Accessing members:
data[1].lambda
Regards
but
julia data[1].lambda=[1., 2.0]
ERROR: type DataType has no field lambda
Now that I have the structure data how do I access the branch members?
On Sunday, February 1, 2015 at 8:07:51 PM UTC+11, Milan Bouchet-Valat
wrote:
Le dimanche 01 février 2015 à 00:35 -0800, alex codoreanu a
écrit :
Hi all,
I'm a new Julia user and I'm starting to write a high-level
multi data
type fits file reader and writer akin to IDL's
mwrfits/mrdfits. I got
most of the dynamics figured out by I can't quite make a
custom
structure. For example, I would like something like:
element = {name::string, lambda::[float_array, 5000
elements],
flux::[float_array, 5000 elements]}
structure = replicate(element, 500)
where structure inherits the members of element and can be
called,
structure[1].name = the name of element 1
strucutre[1].lambda[1] = the first lambda element of the
first
structure
Looks like a composite type would work:
type Element
name::UTF8String
lambda::Vector{Float64}
flux::Vector{Float64}
end
Regards
Re: [julia-users] Parametric vs Abstract typed collections, design question
James, in case you haven't seen it, this is treated _extensively_ in the FAQ. Make a nice cup of tea and pull up a comfy chair before you start reading :-). --Tim On Sunday, February 01, 2015 01:16:19 AM Jutho wrote: As long as not all parameters of a parametric concrete type are fully specified, the type is treated as abstract. So in both cases your collection would be of abstract elements and they would not be stored packed in memory. I don't think what you are requesting is possible, but I might be mistaken. If the elements of the collection are of a concrete type, then applying a function to them should always be the same function. If this were not the case, then type inference could not work.
Re: [julia-users] Re-size image in IJulia Markdown
Can't help you with the markdown issue, but your Images.jl installation is borked. This happens all-to-often for OSX users. See https://github.com/timholy/Images.jl#installation for ways to fix; if none of the linked methods work, please do open an issue. --Tim On Saturday, January 31, 2015 05:40:15 PM Nathan Nesbitt wrote: I am using Markup in IJulia to write notes amongst my code, and want to control the size of an embedded image. To embed the image I'm currently using the code:  This works fine, but doesn't give me control over the image size. Is there any code to add to this line to control the image size? Supposedly for some implementations http://stackoverflow.com/questions/14675913/how-to-change-image-size-markdo wn of Markdown the following code works, but this failed for me  For an altenative I looked into the ImageView package https://github.com/timholy/ImageView.jl by Tim Holy, but got an error when I tried to use this in IJulia (following the suggested syntax) using ImageView img = imread(my_pic.jpg) libversion not defined in image2wand at /Users/Nikola/.julia/v0.3/Images/src/io.jl:304 in _writemime at /Users/Nikola/.julia/v0.3/Images/src/io.jl:198 in base64 at base64.jl:125 in display_dict at /Users/Nikola/.julia/v0.3/IJulia/src/execute_request.jl:34 view(img, pixelspacing = [1,1]) view not defined while loading In[11], in expression starting on line 1 Any suggestions? Thanks! Best, Nate
Re: [julia-users] How should nested local functions be annotated?
It's a long-standing issue that local and anonymous functions allocate (and have poor performance). FastAnonymous.jl and similar packages give you one way around that. --Tim On Saturday, January 31, 2015 08:03:37 PM Kirill Ignatiev wrote: On Saturday, 31 January 2015 21:54:54 UTC-5, Jameson wrote: code_warntype is being a bit misleading there. code inference hasn't yet fully run on the inner function. This is a reduced test case from a larger program, which allocated a lot of memory, and when I got rid of the locally declared function, the memory usage dropped significantly. So at least empirically I think there may be a problem there.
Re: [julia-users] Markdown Strings as Messages
Is this an existing issue somewhere? On Sunday, 1 February 2015 12:18:42 UTC, Christoph Ortner wrote: Thanks for the clarification. It would be really great to have this functionality, especially, if it can be combined with MathJax! Thanks, Christoph
Re: [julia-users] Markdown Strings as Messages
Thanks for the clarification. It would be really great to have this functionality, especially, if it can be combined with MathJax! Thanks, Christoph
Re: [julia-users] Markdown Strings as Messages
No, feel free to open one if you want (ping me too). On 1 February 2015 at 12:18, Christoph Ortner christophortn...@gmail.com wrote: Is this an existing issue somewhere? On Sunday, 1 February 2015 12:18:42 UTC, Christoph Ortner wrote: Thanks for the clarification. It would be really great to have this functionality, especially, if it can be combined with MathJax! Thanks, Christoph
Re: [julia-users] create a multi data type structure in Julia
Le dimanche 01 février 2015 à 00:35 -0800, alex codoreanu a écrit :
Hi all,
I'm a new Julia user and I'm starting to write a high-level multi data
type fits file reader and writer akin to IDL's mwrfits/mrdfits. I got
most of the dynamics figured out by I can't quite make a custom
structure. For example, I would like something like:
element = {name::string, lambda::[float_array, 5000 elements],
flux::[float_array, 5000 elements]}
structure = replicate(element, 500)
where structure inherits the members of element and can be called,
structure[1].name = the name of element 1
strucutre[1].lambda[1] = the first lambda element of the first
structure
Looks like a composite type would work:
type Element
name::UTF8String
lambda::Vector{Float64}
flux::Vector{Float64}
end
Regards
Re: [julia-users] Parametric vs Abstract typed collections, design question
As long as not all parameters of a parametric concrete type are fully specified, the type is treated as abstract. So in both cases your collection would be of abstract elements and they would not be stored packed in memory. I don't think what you are requesting is possible, but I might be mistaken. If the elements of the collection are of a concrete type, then applying a function to them should always be the same function. If this were not the case, then type inference could not work.
[julia-users] Subtraction of the diagonal matrix, how sipler?
I have somethink like this : rand(4,4).-eye(4,4)*5 Qestion : how to simpler subtracted from the diagonal value(5) , Without multiplying matrices I have great and I have to simplify the code. Paul
Re: [julia-users] Help with the findin method
Thank you so much Jiahao!
I see my guess was correct.
What a nice group.
2015-01-31 16:50 GMT-06:00 Jiahao Chen jia...@mit.edu:
Your custom particles type is not iterable, i.e. does not have start, next
and done methods defined. See the manual for details of the iterable
interface.
Note that Julia numbers are iterable, so the following works:
julia findin([1,2,3], 2)
1-element Array{Int64,1}:
2
Thanks,
Jiahao Chen
Staff Research Scientist
MIT Computer Science and Artificial Intelligence Laboratory
Re: [julia-users] Subtraction of the diagonal matrix, how sipler?
Thx, nice. Is the fast way in Julia ? Paul W dniu niedziela, 1 lutego 2015 17:18:03 UTC+1 użytkownik Andreas Noack napisał: This is cheaper: rand(4,4) - 5*I because 5I is a special type that doesn't store all elements. 2015-02-01 11:03 GMT-05:00 paul analyst paul.a...@mail.com javascript: : I have somethink like this : rand(4,4).-eye(4,4)*5 Qestion : how to simpler subtracted from the diagonal value(5) , Without multiplying matrices I have great and I have to simplify the code. Paul
[julia-users] Re: Robust Inner Products
I realise I didn't actually answer your question: I can't speak as to whether it will be accepted in Base (you will probably have to open an issue or pull request to start a discussion), but at the very least it would be useful to at least have in a package somewhere. If you don't want to create your own, I'd be happy to incorporate it into DoubleDouble.jl. Simon On Sunday, 1 February 2015 15:20:29 UTC, Christoph Ortner wrote: thanks for the suggestions; indeed, Rumpf's paper is my main reference :) for these things.
[julia-users] Memory usage and speed in nested loop.
I have two versions of an example function that calculates a number by looping over all pair of points. In the first one I use a 2d-array and access points with [:,i] syntax to get the coordinates. In the second version of the function I instead creates an array of Point-types (each Point has a x and y coordinate). I then access the coordinate like point.x, point.y etc. These two functions takes vastly different time and memory usage. This is the first function: function slow() srand(1234) points = randn(2, 5000) n_points::Int = size(points,2) cum = 0.0 for i in 1:n_points for j in (i+1):n_points point_2 = points[:, j] cum += point_2[1] end end return cum end This is the fast version with the Point types: immutable Point x::Float64 y::Float64 end function fast() srand(1234) points = randn(2, 5000) n_points = size(points, 2) cum= 0.0 # Create array of points points_vec = Point[] for i in 1:n_points push!(points_vec, Point( points [1,i], points [2,i])) end for i in 1:n_points for j in (i+1):n_points point_2 = points_vec[j] cum += point_2.x end end return cum end Running @time println(slow()) @time println(fast()) now gives: -23952.535945302105 elapsed time: 0.954317047 seconds (1055 MB allocated, 3.78% gc time in 48 pauses with 0 full sweep) -23952.535945302105 elapsed time: 0.025171914 seconds (1 MB allocated) The slow version takes 50 times longer and consumes 1000x the memory. Running the functions with memory tacker gives: - - - - function slow() 28688 srand(1234) 80048 points = randn(2, 5000) 0 n_points::Int = size(points,2) 0 cum = 0.0 0 for i in 1:n_points 0 for j in (i+1):n_points 109978 point_2 = points[:, j] 0 cum += point_2[1] - end - end 0 return cum - end - - - - immutable Point - x::Float64 - y::Float64 - end - - function fast() 2540964 srand(1234) 80048 points = randn(2, 5000) 0 n_points = size(points, 2) 0 cum= 0.0 - - # Create array of points 48 points_vec = Point[] 0 for i in 1:n_points 263112 push!(points_vec, Point( points [1,i], points [2,i])) - end - 0 for i in 1:n_points 0 for j in (i+1):n_points 0 point_2 = points_vec[j] 0 cum += point_2.x - end - end 0 return cum - end - - - - @time println(slow()) - @time println(fast()) - - So what seems to take all the memory is point_2 = points[:, j] Maybe some copying is performed when slicing but I have tried replacing it with sub and slice etc (that shouldnt copy?) and it just get worse. Are there some alignment issues? I have tried both in 0.3.5 and 0.4 with the same results. Any help? Best regards, Kristoffer Carlsson
Re: [julia-users] Memory usage and speed in nested loop.
If you're using sub or slice, your performance should be vastly better on 0.4 than 0.3, but as you observed it will still be awful. In the long run (maybe even by the time 0.4 is released?), we hope that in such loops sub/slice won't actually create a new object and allocate memory---it will be transparently elided by the compiler. I think the main roadblock currently is the fact that immutables with tuple fields (see the definition of SubArray) currently do not inline the tuple, instead holding a reference to a heap-allocated object. That basically prevents further optimization. For improvements, the main issue to watch is https://github.com/JuliaLang/julia/issues/8974. Manual devectorization or manual immutables like your Point type are currently your best bet. Best, --Tim On Sunday, February 01, 2015 06:35:05 AM Kristoffer Carlsson wrote: I have two versions of an example function that calculates a number by looping over all pair of points. In the first one I use a 2d-array and access points with [:,i] syntax to get the coordinates. In the second version of the function I instead creates an array of Point-types (each Point has a x and y coordinate). I then access the coordinate like point.x, point.y etc. These two functions takes vastly different time and memory usage. This is the first function: function slow() srand(1234) points = randn(2, 5000) n_points::Int = size(points,2) cum = 0.0 for i in 1:n_points for j in (i+1):n_points point_2 = points[:, j] cum += point_2[1] end end return cum end This is the fast version with the Point types: immutable Point x::Float64 y::Float64 end function fast() srand(1234) points = randn(2, 5000) n_points = size(points, 2) cum= 0.0 # Create array of points points_vec = Point[] for i in 1:n_points push!(points_vec, Point( points [1,i], points [2,i])) end for i in 1:n_points for j in (i+1):n_points point_2 = points_vec[j] cum += point_2.x end end return cum end Running @time println(slow()) @time println(fast()) now gives: -23952.535945302105 elapsed time: 0.954317047 seconds (1055 MB allocated, 3.78% gc time in 48 pauses with 0 full sweep) -23952.535945302105 elapsed time: 0.025171914 seconds (1 MB allocated) The slow version takes 50 times longer and consumes 1000x the memory. Running the functions with memory tacker gives: - - - - function slow() 28688 srand(1234) 80048 points = randn(2, 5000) 0 n_points::Int = size(points,2) 0 cum = 0.0 0 for i in 1:n_points 0 for j in (i+1):n_points 109978 point_2 = points[:, j] 0 cum += point_2[1] - end - end 0 return cum - end - - - - immutable Point - x::Float64 - y::Float64 - end - - function fast() 2540964 srand(1234) 80048 points = randn(2, 5000) 0 n_points = size(points, 2) 0 cum= 0.0 - - # Create array of points 48 points_vec = Point[] 0 for i in 1:n_points 263112 push!(points_vec, Point( points [1,i], points [2,i])) - end - 0 for i in 1:n_points 0 for j in (i+1):n_points 0 point_2 = points_vec[j] 0 cum += point_2.x - end - end 0 return cum - end - - - - @time println(slow()) - @time println(fast()) - - So what seems to take all the memory is point_2 = points[:, j] Maybe some copying is performed when slicing but I have tried replacing it with sub and slice etc (that shouldnt copy?) and it just get worse. Are there some alignment issues? I have tried both in 0.3.5 and 0.4 with the same results. Any help? Best regards, Kristoffer Carlsson
Re: [julia-users] Subtraction of the diagonal matrix, how sipler?
I think so, but it neither take long time julia let A = rand(4,4); @time for i = 1:10^6;A - 5.0*eye(4);end end; elapsed time: 0.177621144 seconds (534 MB allocated, 5.71% gc time in 25 pauses with 0 full sweep) julia let A = rand(4,4); @time for i = 1:10^6;A - 5.0*I;end end; elapsed time: 0.053749097 seconds (167 MB allocated, 5.04% gc time in 8 pauses with 0 full sweep) 2015-02-01 11:49 GMT-05:00 paul analyst paul.anal...@mail.com: Thx, nice. Is the fast way in Julia ? Paul W dniu niedziela, 1 lutego 2015 17:18:03 UTC+1 użytkownik Andreas Noack napisał: This is cheaper: rand(4,4) - 5*I because 5I is a special type that doesn't store all elements. 2015-02-01 11:03 GMT-05:00 paul analyst paul.a...@mail.com: I have somethink like this : rand(4,4).-eye(4,4)*5 Qestion : how to simpler subtracted from the diagonal value(5) , Without multiplying matrices I have great and I have to simplify the code. Paul
Re: [julia-users] Symbol to string
And more generally, for all types that makes sense to convert between, you can use the convert function convert(String, :blah) (or maybe better, to avoid type instability issues) convert(ASCIIString, :blah) convert(UTF8String, :blah) In 0.4 the default constructor for all types will fallback to convert, so for your own types, you usually just need to add a convert definition. søndag 1. februar 2015 16.29.48 UTC+1 skrev Milan Bouchet-Valat følgende: Le dimanche 01 février 2015 à 07:18 -0800, Arshak Navruzyan a écrit : Hello, A really basic question how do I turn a symbol into a string ? :blah - blah julia string(:blah) blah Easy, isn't it? Regards
Re: [julia-users] Subtraction of the diagonal matrix, how sipler?
This is cheaper: rand(4,4) - 5*I because 5I is a special type that doesn't store all elements. 2015-02-01 11:03 GMT-05:00 paul analyst paul.anal...@mail.com: I have somethink like this : rand(4,4).-eye(4,4)*5 Qestion : how to simpler subtracted from the diagonal value(5) , Without multiplying matrices I have great and I have to simplify the code. Paul
Re: [julia-users] Markdown Strings as Messages
Markdown.jl lives in base Julia now so it should probably go there. On 1 February 2015 at 15:18, Christoph Ortner christophortn...@gmail.com wrote: should this go in Docile, Lexicon, or Julialang? Christoph
[julia-users] Re: Robust Inner Products
thanks for the suggestions; indeed, Rumpf's paper is my main reference :) for these things.
Re: [julia-users] Symbol to string
Le dimanche 01 février 2015 à 07:18 -0800, Arshak Navruzyan a écrit : Hello, A really basic question how do I turn a symbol into a string ? :blah - blah julia string(:blah) blah Easy, isn't it? Regards
[julia-users] Re: select! with range creating a memory allocation
This issue will fix itself when `a[r]` returns a subarray with 0.4 (this hasn't landed in master yet, and reminds me that the pending change will require a huge documentation effort that change affect APIs). The improved garbage collection that was merged in master recently will likely greatly reduce the performance penalty for such short lived allocations. Ivar søndag 1. februar 2015 11.53.02 UTC+1 skrev julia.e...@gmail.com følgende: I realize this is a more developer issue, but I'm wondering if anyone else thinks it would be a good idea for select! to be changed to not return A[r] (which allocates memory). I think it could return (A[r.start], A[r.stop]), sub(A, r) or even nothing. As it stands it seems like a performance penalty that can be avoided since the rest of the function should operate on memory in place. In my own project I've made a local copy of select for this reason and taken out the return value.
Re: [julia-users] Markdown Strings as Messages
should this go in Docile, Lexicon, or Julialang? Christoph
[julia-users] Symbol to string
Hello, A really basic question how do I turn a symbol into a string ? :blah - blah Thanks
[julia-users] Re: Data structure with variable length outputs
As you probably realized vcat makes a copy of the vector, so it is inefficient when you use it repeatedly. Julia provides the push! and append! functions so that you can efficiently add elements to the end of a vector. There is also a sizehint! function if you know how many elements there will ultimately be, and want to save a few copies when the array grows. søndag 1. februar 2015 15.31.40 UTC+1 skrev Christopher Fisher følgende: Hi all- I am trying to figure out a graceful way to store output from a model simulation. Each simulated trial produces a single reaction time, a single choice and a vector of visual fixations generated by a Markov chain. The complicating factor is that the size of the vector of visual fixations varies on each simulated trial and I would like to generate multiple simulated trials. Is there a way to store these outputs in a data structure that will be easy to access in other functions? A related issue is the dynamic nature of the vector size. I am currently using vcat to add new values to the vector. Is there a more efficient method? Thank you in advance for your help.
[julia-users] The sub function behaves differently in v0.3 and master
Hi,
I noticed that the sub function behaves differently in master and version
0.3.5, when handling data of type Array{Float64, 1}. I am not sure if the
change is intentional.
The following works as expected on Julia master:
*julia* *sub([1.0; 2; 3; 4], 1:3, :)*
but, fails in version 0.3.5 with the following error:
*ERROR: `sub` has no method matching sub(::Array{Float64,1},
::(UnitRange{Int64},UnitRange{Int64}))*
* in sub at subarray.jl:80** in sub at subarray.jl:132*
Is this a bug in Julia 0.3.5 or master?
This came up in this pull request:
https://github.com/dancasimiro/WAV.jl/pull/20. I just figured out that my
fix is broken too.
Thanks.
Re: [julia-users] Parametric vs Abstract typed collections, design question
Thanks, that's kind of what I expected. @Tim: I found some stuff in there (and in the very helpful Types section), but never saw explicitly whether a collection of unparametrized parametric type offered any additional benefit to the compiler than one of just abstract type. (i.e. Rational[] vs Real[]). Since the container type isn't concrete, I figured it probably wouldn't offer any benefit, but thought I'd ask. - Jim On Sun, Feb 1, 2015 at 5:07 AM, Tim Holy tim.h...@gmail.com wrote: James, in case you haven't seen it, this is treated _extensively_ in the FAQ. Make a nice cup of tea and pull up a comfy chair before you start reading :-). --Tim On Sunday, February 01, 2015 01:16:19 AM Jutho wrote: As long as not all parameters of a parametric concrete type are fully specified, the type is treated as abstract. So in both cases your collection would be of abstract elements and they would not be stored packed in memory. I don't think what you are requesting is possible, but I might be mistaken. If the elements of the collection are of a concrete type, then applying a function to them should always be the same function. If this were not the case, then type inference could not work.
Re: [julia-users] Re: Data structure with variable length outputs
With regards to the part about a data structure for storing your results, http://docs.julialang.org/en/latest/manual/types/#composite-types might be what you're looking for. --Tim On Sunday, February 01, 2015 11:34:50 AM Ivar Nesje wrote: As you probably realized vcat makes a copy of the vector, so it is inefficient when you use it repeatedly. Julia provides the push! and append! functions so that you can efficiently add elements to the end of a vector. There is also a sizehint! function if you know how many elements there will ultimately be, and want to save a few copies when the array grows. søndag 1. februar 2015 15.31.40 UTC+1 skrev Christopher Fisher følgende: Hi all- I am trying to figure out a graceful way to store output from a model simulation. Each simulated trial produces a single reaction time, a single choice and a vector of visual fixations generated by a Markov chain. The complicating factor is that the size of the vector of visual fixations varies on each simulated trial and I would like to generate multiple simulated trials. Is there a way to store these outputs in a data structure that will be easy to access in other functions? A related issue is the dynamic nature of the vector size. I am currently using vcat to add new values to the vector. Is there a more efficient method? Thank you in advance for your help.
Re: [julia-users] Markdown Strings as Messages
created issue [10009](https://github.com/JuliaLang/julia/issues/10009)
[julia-users] Re: Data structure with variable length outputs
Thank you Ivar and Tim. Using append gave me a 3 fold improvement in speed and I'll look into the composite types. On Sunday, February 1, 2015 at 9:31:40 AM UTC-5, Christopher Fisher wrote: Hi all- I am trying to figure out a graceful way to store output from a model simulation. Each simulated trial produces a single reaction time, a single choice and a vector of visual fixations generated by a Markov chain. The complicating factor is that the size of the vector of visual fixations varies on each simulated trial and I would like to generate multiple simulated trials. Is there a way to store these outputs in a data structure that will be easy to access in other functions? A related issue is the dynamic nature of the vector size. I am currently using vcat to add new values to the vector. Is there a more efficient method? Thank you in advance for your help.
[julia-users] Re: Robust Inner Products
many thanks - well I will implement it first of all, and then see where it could go. Christoph
[julia-users] Re: select! with range creating a memory allocation
Thanks for the reply. To start using 0.4 will I just have to gamble on a nightly windows installer? On Sunday, February 1, 2015 at 1:11:40 PM UTC-6, Ivar Nesje wrote: This issue will fix itself when `a[r]` returns a subarray with 0.4 (this hasn't landed in master yet, and reminds me that the pending change will require a huge documentation effort that change affect APIs). The improved garbage collection that was merged in master recently will likely greatly reduce the performance penalty for such short lived allocations. Ivar søndag 1. februar 2015 11.53.02 UTC+1 skrev julia.e...@gmail.com følgende: I realize this is a more developer issue, but I'm wondering if anyone else thinks it would be a good idea for select! to be changed to not return A[r] (which allocates memory). I think it could return (A[r.start], A[r.stop]), sub(A, r) or even nothing. As it stands it seems like a performance penalty that can be avoided since the rest of the function should operate on memory in place. In my own project I've made a local copy of select for this reason and taken out the return value.
[julia-users] Re: select! with range creating a memory allocation
Yes, if you are on windows, the nightly installer is the easiest way. Be sure to keep the old downloads, and remember what versions you use so that you can revert if a new change causes trouble with your setup. (How careful you must be, depends on how acceptable it is for you to have a broken Julia install until you adapt your code to a breaking change)
Re: [julia-users] The sub function behaves differently in v0.3 and master
SubArrays have been entirely rewritten in 0.4, and can do quite a few tricks
that the old ones can't. Changing the dimensionality of the view compared to
the parent, as in your example, is one of them. Here's another example of
something you simply can't do on 0.3:
julia A = reshape(1:15, 3, 5)
3x5 Array{Int64,2}:
1 4 7 10 13
2 5 8 11 14
3 6 9 12 15
julia b = sub(A, [2, 7, 8])
3-element SubArray{Int64,1,Array{Int64,2},(Array{Int64,1},),0}:
2
7
8
julia b[2] = -1
-1
julia A
3x5 Array{Int64,2}:
1 4 -1 10 13
2 5 8 11 14
3 6 9 12 15
If anything, the divergence between the two will grow further once
https://github.com/JuliaLang/julia/issues/9874 is addressed.
Best,
--Tim
On Sunday, February 01, 2015 12:02:56 PM Daniel Casimiro wrote:
Hi,
I noticed that the sub function behaves differently in master and version
0.3.5, when handling data of type Array{Float64, 1}. I am not sure if the
change is intentional.
The following works as expected on Julia master:
*julia* *sub([1.0; 2; 3; 4], 1:3, :)*
but, fails in version 0.3.5 with the following error:
*ERROR: `sub` has no method matching sub(::Array{Float64,1},
::(UnitRange{Int64},UnitRange{Int64}))*
* in sub at subarray.jl:80** in sub at subarray.jl:132*
Is this a bug in Julia 0.3.5 or master?
This came up in this pull request:
https://github.com/dancasimiro/WAV.jl/pull/20. I just figured out that my
fix is broken too.
Thanks.
[julia-users] [Tips] The fastest way of reading csv files for Matlab users
Hi, This is to share my finding of using the Juila for Matlab users. I have a few big size data in csv format to open from the Juila and it tooks at least 3 minutes to read. However, if I convert the file into Matlab format (.mat) and load the file with Matlab, it tooks only one minute. I searched the Julia and find the MAT package. https://github.com/simonster/MAT.jl Instead of the csv file, I open the file with Matlab format data using the MAT package and it took only *a few second* !! using MAT MN=@sprintf(MODEL_%02d.mat,2); # this code is to select the 2nd matlab file for me. #check the name of the variable name you saved in Matlab first file = matopen(MN); # you can type your file name directly from here like, MODEL_02.mat varnames = names(file); #I found *MODEL* was the name of the varnames close(file) # Now call the variable from Julia file = matopen(MN); MODEL=read(file, *MODEL*); # Enter the name of the varnames above at and assign variable name again!! close(file) # Now whether you open the righ file size(MODEL) It's fantastic and this prove Julia has something more than other languages but still Julia is lack of tutorials to cover. I suggest to share this kind of your findings for the progress of the Julia and for the convenience of the users. Thank you Julia. Jase
