[julia-users] confusion about Date comprehension types
I tested 2 ways of constructing date array. But I got two different
types of the arrays from the two ways. How can I make them the same?
What is the proper Date type? At least, I hope not to use the Any type.
--
julia dats = [date(2014, 7, ii) for ii=1:4]
4-element Array{Date{C:Calendar},1}:
2014-07-01
2014-07-02
2014-07-03
2014-07-04
--
julia dates
4-element DataArray{UTF8String,1}:
2010/1/4
2010/1/5
2010/1/6
2010/1/7
julia [date(dates[i]) for i=1:length(dates)]
4-element Array{Any,1}:
2010-01-04
2010-01-05
2010-01-06
2010-01-07
[julia-users] what is the easiest way to convert array type?
I have an Array{Any,1}, but I want to convert to Array{String,1}. The
only way I know is through comprehension.
julia dt
3-element Array{Any,1}:
2010/1/4T15:00:00
2010/1/5T15:00:00
2010/1/6T15:00:00
julia dts = [convert(String, dt[i]) for i=1:length(dt)]
3-element Array{String,1}:
2010/1/4T15:00:00
2010/1/5T15:00:00
2010/1/6T15:00:00
Re: [julia-users] Re: what is the easiest way to convert array type?
Thanks. Didn't know about that syntax. Now with it, I might prefer the
following as Array{String,1} is exactly what I want.
julia dts1 = convert(Array{String,1},dt)
3-element Array{String,1}:
2010/1/4T15:00:00
2010/1/5T15:00:00
2010/1/6T15:00:00
On 2014年07月25日 10:40, Miles Lubin wrote:
How about convert(Vector{String},dt)?
On Thursday, July 24, 2014 8:39:02 PM UTC-6, K leo wrote:
I have an Array{Any,1}, but I want to convert to Array{String,1}. The
only way I know is through comprehension.
julia dt
3-element Array{Any,1}:
2010/1/4T15:00:00
2010/1/5T15:00:00
2010/1/6T15:00:00
julia dts = [convert(String, dt[i]) for i=1:length(dt)]
3-element Array{String,1}:
2010/1/4T15:00:00
2010/1/5T15:00:00
2010/1/6T15:00:00
[julia-users] string array concatenates with a string not working?
julia VA
3-element Array{ASCIIString,1}:
A
B
C
julia VA * T
ERROR: `*` has no method matching *(::Array{ASCIIString,1}, ::ASCIIString)
Re: [julia-users] string array concatenates with a string not working?
Just found it works on DataArray:
julia da = DataArray([A, B, C])
3-element DataArray{ASCIIString,1}:
A
B
C
julia da * T
3-element DataArray{Any,1}:
AT
BT
CT
On 2014年07月25日 11:57, cnbiz850 wrote:
That sounds confusing. You just mentioned that Vector{String} is
semantically equivalent to Array{String, 1}.
On 2014年07月25日 11:53, John Myles White wrote:
Arrays of strings aren’t part of a vector space. There’s no reason
you should be able to multiply them by a scalar.
— John
[julia-users] how to insert at index?
I did the following on a DataFrame, but got error. What should I do instead? julia df = insert!(df, 25, dfa) ERROR: `insert!` has no method matching insert!(::DataFrame, ::Int64, ::DataFrame)
Re: [julia-users] DataFrames.jl problem
using the latest build and most updated packages, I don't have that problem. | | |_| | | | (_| | | Version 0.3.0-prerelease+3863 (2014-06-24 04:00 UTC) _/ |\__'_|_|_|\__'_| | Commit c300f5f* (0 days old master) |__/ | x86_64-linux-gnu julia using DataFrames julia
Re: [julia-users] Re: juliabloggers.com is now live!
I use g2reader (http://www.g2reader.com) and can't subscribe to this. Don't know why. It complains about: Entered url doesn't contain valid feed or doesn't link to feed. It is also possible feed contains no items. On 06/17/2014 08:38 PM, Randy Zwitch wrote: My apologies, I think the link got mangled last time. Here it is again: http://www.juliabloggers.com/feed/ http://www.juliabloggers.com/feed/ On Monday, June 16, 2014 9:18:45 PM UTC-4, K leo wrote: Is there something wrong with the feed? http://www.juliabloggers.com/feed/ juliabloggers.com http://www.juliabloggers.com/feed/juliabloggers.com Entered url doesn't contain valid feed or doesn't link to feed. It is also possible feed contains no items.
Re: [julia-users] Re: juliabloggers.com is now live!
Is there something wrong with the feed? http://www.juliabloggers.com/feed/ juliabloggers.com Entered url doesn't contain valid feed or doesn't link to feed. It is also possible feed contains no items. On 06/16/2014 08:52 PM, Randy Zwitch wrote: Nothing shady about it at all and a good reminder I need to add a visible RSS icon. Here's the feed: http://www.juliabloggers.com/feed/ On Monday, June 16, 2014 7:32:49 AM UTC-4, Tomas Lycken wrote: Nice! I'm missing a feature: something to help me pull this into my RSS reader. If it feels shady to re-publish an aggregated blog like this in RSS, at least a list of the feeds that are currently pulled in would be nice, but ultimately I'd like to add juliabloggers.com http://juliabloggers.com to my feedly and get everything posted there - and if someone comes in tomorrow and adds a new feed to the site, I get that content too. // T On Monday, June 16, 2014 1:17:47 PM UTC+2, Randy Zwitch wrote: Hey everyone - Several posts had popped up over the past few month about creating a centralized location for Julia content. I'm proud to announce that http://www.juliabloggers.com/ http://www.juliabloggers.com/ is now live! This is still very much a work-in-progress, as the theme is fairly vanilla and I need to work out some oddities with how the content is ingested, but the concept certainly works. If you'd like to contribute your content to Julia Bloggers, all it takes is submitting an RSS/Atom feed via this link: http://www.juliabloggers.com/julia-bloggers-submit-rss-feed/ http://www.juliabloggers.com/julia-bloggers-submit-rss-feed/ Once your link is imported into Julia Bloggers, that's it. The site will regularly check your feed for new content, then post it to Julia Bloggers once it becomes available. To-Do: While the current theme adds an author to each post, it is my intention to put a larger attribution section for each post, to make it clear the post owner and a link back to the original blog location (similar to how R-Bloggers has it at the end of each post). Logo: If anyone wants to create a logo, perhaps modifying the current Julia SVG code to read 'JuliaBloggers' or something similar, that would be fantastic. The header needs to be 960x250 or so, but if you make it larger/higher resolution I can deal with the sizing I need. We've already got 3 contributors so far, and the content is getting posted to Twitter via https://twitter.com/juliabloggers https://twitter.com/juliabloggers. If there are any questions or comments, please comment here. Thanks! Randy
[julia-users] What to do with julia's core dumped
$ julia _ _ _ _(_)_ | A fresh approach to technical computing (_) | (_) (_)| Documentation: http://docs.julialang.org _ _ _| |_ __ _ | Type help() to list help topics | | | | | | |/ _` | | | | |_| | | | (_| | | Version 0.3.0-prerelease+3680 (2014-06-15 00:50 UTC) _/ |\__'_|_|_|\__'_| | Commit dff05bb* (0 days old master) |__/ | x86_64-linux-gnu julia include(DelDup.jl) Segmentation fault (core dumped) $
[julia-users] Re: What to do with julia's core dumped
The core dump has to do with removing sys.so. When I restored it, julia did not core dump, instead, it printed out errors in my code. On 06/16/2014 07:18 AM, cnbiz850 wrote: $ julia _ _ _ _(_)_ | A fresh approach to technical computing (_) | (_) (_)| Documentation: http://docs.julialang.org _ _ _| |_ __ _ | Type help() to list help topics | | | | | | |/ _` | | | | |_| | | | (_| | | Version 0.3.0-prerelease+3680 (2014-06-15 00:50 UTC) _/ |\__'_|_|_|\__'_| | Commit dff05bb* (0 days old master) |__/ | x86_64-linux-gnu julia include(DelDup.jl) Segmentation fault (core dumped) $
Re: [julia-users] what is the deal with !
Thanks for the explanation. That cleared my misunderstanding. I wonder how other new guys feel, but to me, the ! seemed magical: with it, the modified argument is passed back; without it not. Now I understand it is simply a convention and does not do anything. But still, the question can always remain when looking at a function's definition: which of the many arguments' values get modified and passed back? I feel like some other languages' way of defining function arguments: it is clear that the argument passed by reference gets modified and passed back. On 06/13/2014 04:57 PM, Tomas Lycken wrote: Actually, the bang (!) ending of function names is just a convention - it doesn't make the function do anything special, or treat it any other way than without the bang. For example, with the definition ``` push = push! ``` you could very well do `push(a, 3)` to append `3` at the end of the array `a`, with precisely the same effect as if you'd done `push!(a,3)`. If you write a new function that mutates its arguments, it is conventional to use the bang regardless of if the mutated argument is e.g. array or some other composite type. However, while this convention is indeed very old, there's probably old code lying around where it isn't used, and other new code where the author forgot or was too lazy to make sure all mutating function names ended in with a bang. And still today this convention is not enforced in any way: it's perfectly legal to define a new mutating function without a bang at the end of the name. There is, however, some vaguely related discussion about introducing for example notation for pure functions https://github.com/JuliaLang/julia/issues/414, that might spill over on this convention if it is included in the language. // T On Friday, June 13, 2014 4:08:17 AM UTC+2, K leo wrote: Thanks. It says this: By convention, function names ending with an exclamation point (!) modify their arguments. Some functions have both modifying (e.g., sort!) and non-modifying (sort) versions. But my experience is a little inconsistent. I noticed that is what it does to array arguments, but to other arguments (like composite types) it seems not necessary. Am I missing something? Also, it is a special character. So perhaps it is better listed under operators section in the documentation. On 06/13/2014 09:58 AM, Jacob Quinn wrote: It's mentioned here in the Some general notes section, but if you have suggestions of other places it should be mentioned, I'm sure it wouldn't hurt! http://docs.julialang.org/en/latest/stdlib/base/#introduction http://docs.julialang.org/en/latest/stdlib/base/#introduction -Jacob On Thu, Jun 12, 2014 at 9:53 PM, cnbiz850 cnbi...@gmail.com javascript: mailto:cnbi...@gmail.com javascript: wrote: Can't find a description. I guess that when it is used after a function name it makes the modified array argument passed back to the caller. Is that right, or is that all it is used for?
[julia-users] DataFrames delete row very slow
I use the following to delete a row: function deleterow(df::DataFrame, row::Int) return df[[1:row-1, row+1:end], :] end The time it takes to delete 1000 rows in a 22,000-row df is about 16 seconds. Are there more efficient ways to do it?
Re: [julia-users] Re: DataFrames delete row very slow
Thanks very much Matt. It takes no time now.
On 06/12/2014 10:35 PM, Matt Bauman wrote:
You're making 1000 slightly different copies of your huge dataframe by
doing it one-by-one. Can you do all 1000 removals at once? Even if
you're finding the rows to remove iteratively, simply store a list of
the rows to remove and batch the removals all together.
Perhaps something like:
function deleterows(df::DataFrame, rows::Array{Int,1})
return df[setdiff(1:end,rows), :]
end
On Thursday, June 12, 2014 10:27:14 AM UTC-4, K leo wrote:
I use the following to delete a row:
function deleterow(df::DataFrame, row::Int)
return df[[1:row-1, row+1:end], :]
end
The time it takes to delete 1000 rows in a 22,000-row df is about 16
seconds.
Are there more efficient ways to do it?
[julia-users] what is the deal with !
Can't find a description. I guess that when it is used after a function name it makes the modified array argument passed back to the caller. Is that right, or is that all it is used for?
Re: [julia-users] what is the deal with !
Thanks. It says this: By convention, function names ending with an exclamation point (!) modify their arguments. Some functions have both modifying (e.g., sort!) and non-modifying (sort) versions. But my experience is a little inconsistent. I noticed that is what it does to array arguments, but to other arguments (like composite types) it seems not necessary. Am I missing something? Also, it is a special character. So perhaps it is better listed under operators section in the documentation. On 06/13/2014 09:58 AM, Jacob Quinn wrote: It's mentioned here in the Some general notes section, but if you have suggestions of other places it should be mentioned, I'm sure it wouldn't hurt! http://docs.julialang.org/en/latest/stdlib/base/#introduction -Jacob On Thu, Jun 12, 2014 at 9:53 PM, cnbiz850 cnbiz...@gmail.com mailto:cnbiz...@gmail.com wrote: Can't find a description. I guess that when it is used after a function name it makes the modified array argument passed back to the caller. Is that right, or is that all it is used for?
Re: [julia-users] Trying to install 0.3 prerelease on Ubuntu but keep geting 0.2.1
On 06/10/2014 06:30 AM, J Luis wrote: Hi, I'm trying to install 0.3 via PPA (just updated to Ubuntu 14.01 to see if worked better as I had other issues with 13.10) but all I get is 0.2.1. I am on Xubuntu 14.04 and it works fine.
[julia-users] how to print out part of a row in DataFrame?
I only got the following formatted display but not my values. To me this is really not desired, does everyone prefer this? Can I get a printout of the values just as I print out a row of an array? julia println(df[jj, 1:20]) 1x20 DataFrame |---|--||-| | Col # | Name | Eltype | Missing | | 1 | x1 | Int64 | 0 | | 2 | x2 | Int64 | 0 | | 3 | x3 | Int64 | 0 | | 4 | x4 | Int64 | 0 | | 5 | x5 | Int64 | 0 | | 6 | x6 | Int64 | 0 | | 7 | x7 | Int64 | 0 | | 8 | x8 | Int64 | 0 | | 9 | x9 | Int64 | 0 | | 10| x10 | Int64 | 0 | | 11| x11 | Int64 | 0 | | 12| x12 | Int64 | 0 | | 13| x13 | Int64 | 0 | | 14| x14 | Int64 | 0 | | 15| x15 | Int64 | 0 | | 16| x16 | Int64 | 0 | | 17| x17 | Int64 | 0 | | 18| x18 | Int64 | 0 | | 19| x19 | Int64 | 0 | | 20| x20 | Int64 | 0 |
Re: [julia-users] Re: how to print out part of a row in DataFrame?
Thanks John for the update. Do I need to do a clone to get the new change? I think there are two issues here. One is to display df, a row of it, or part of a row, like julia df julia df[3, 1:20] The other is to print out (to the terminal or to a file). On the first issue, I hope DataFrames can adopt a similar behavior of arrays (when the user tries to display an array that is large, julia prints out ... in between the data). This is not only helpful to the user but is also consistent with the overall julia style. On the second, if an entire df is to be printed to the terminal, perhaps it should opt to print a summary only. If a row is to be printed, it should always print out the data, however many elements. On 06/10/2014 10:43 AM, John Myles White wrote: Yup, this is the behavior that just got removed since we’ve had so many complaints. — John On Jun 9, 2014, at 7:42 PM, Taylor Maxwell taylor.maxw...@gmail.com wrote: If your dataframe has 6 or more columns then it prints this summary. If you index less than 6 columns it will print ok. You can force it to spit it all out with showall(df) but that may not be entirely legible. There may be other ways to display it.
Re: [julia-users] PSA: new ~/.julia_history format
Since I deleted .julia_history2 yesterday, I don't have the history errors now. Don't know if that was the culprit. On 06/08/2014 08:02 AM, Stefan Karpinski wrote: Please do let me know of it continues to be broken for you. On Jun 7, 2014, at 6:41 PM, cnbiz850 cnbiz...@gmail.com wrote: Perhaps it does not happen at every start. More likely at the start of every new day. I just deleted .julia_history2, restarted julia, and did not get that error. Will see tomorrow. On 06/08/2014 06:30 AM, Stefan Karpinski wrote: That's definitely a problem. Could you file an issue? Ideally, including example contents from a produced ~/.julia_history file. On Sat, Jun 7, 2014 at 6:28 PM, cnbiz850 cnbiz...@gmail.com mailto:cnbiz...@gmail.com wrote: Lately, every time I start up julia I got the following error. And every time I have to delete ~/.julia_history. Why? -- $ julia _ _ _ _(_)_ | A fresh approach to technical computing (_) | (_) (_)| Documentation: http://docs.julialang.org _ _ _| |_ __ _ | Type help() to list help topics | | | | | | |/ _` | | | | |_| | | | (_| | | Version 0.3.0-prerelease+3512 (2014-06-05 19:22 UTC) _/ |\__'_|_|_|\__'_| | Commit e16ee44* (2 days old master) |__/ | x86_64-linux-gnu ERROR: Invalid history format. If you have a ~/.julia_history file left over from an older version of Julia, try renaming or deleting it. in hist_from_file at REPL.jl:277 in setup_interface at REPL.jl:594 in run_frontend at REPL.jl:718 in run_repl at REPL.jl:162 in _start at client.jl:396
Re: [julia-users] PSA: new ~/.julia_history format
Lately, every time I start up julia I got the following error. And every time I have to delete ~/.julia_history. Why? -- $ julia _ _ _ _(_)_ | A fresh approach to technical computing (_) | (_) (_)| Documentation: http://docs.julialang.org _ _ _| |_ __ _ | Type help() to list help topics | | | | | | |/ _` | | | | |_| | | | (_| | | Version 0.3.0-prerelease+3512 (2014-06-05 19:22 UTC) _/ |\__'_|_|_|\__'_| | Commit e16ee44* (2 days old master) |__/ | x86_64-linux-gnu ERROR: Invalid history format. If you have a ~/.julia_history file left over from an older version of Julia, try renaming or deleting it. in hist_from_file at REPL.jl:277 in setup_interface at REPL.jl:594 in run_frontend at REPL.jl:718 in run_repl at REPL.jl:162 in _start at client.jl:396
Re: [julia-users] PSA: new ~/.julia_history format
Perhaps it does not happen at every start. More likely at the start of every new day. I just deleted .julia_history2, restarted julia, and did not get that error. Will see tomorrow. On 06/08/2014 06:30 AM, Stefan Karpinski wrote: That's definitely a problem. Could you file an issue? Ideally, including example contents from a produced ~/.julia_history file. On Sat, Jun 7, 2014 at 6:28 PM, cnbiz850 cnbiz...@gmail.com mailto:cnbiz...@gmail.com wrote: Lately, every time I start up julia I got the following error. And every time I have to delete ~/.julia_history. Why? -- $ julia _ _ _ _(_)_ | A fresh approach to technical computing (_) | (_) (_)| Documentation: http://docs.julialang.org _ _ _| |_ __ _ | Type help() to list help topics | | | | | | |/ _` | | | | |_| | | | (_| | | Version 0.3.0-prerelease+3512 (2014-06-05 19:22 UTC) _/ |\__'_|_|_|\__'_| | Commit e16ee44* (2 days old master) |__/ | x86_64-linux-gnu ERROR: Invalid history format. If you have a ~/.julia_history file left over from an older version of Julia, try renaming or deleting it. in hist_from_file at REPL.jl:277 in setup_interface at REPL.jl:594 in run_frontend at REPL.jl:718 in run_repl at REPL.jl:162 in _start at client.jl:396
Re: [julia-users] Re: how to use the iterator without loops?
Thanks again for the help. Yes, I do know the number of dimensions before the iterations start, but it is high, as high as 50, and is different under different situations. So I try to simplify code for that. The cartesian package is interesting and I will study it. Besides that, is there any other ways to achieve it? On 06/06/2014 11:07 AM, andrew cooke wrote: do you mean you need to iterate in multiple dimensions, but you don't know beforehand how many dimensions? i'm pretty sure the cartesian package would help in that case. http://julia.readthedocs.org/en/latest/devdocs/cartesian/ On Thursday, 5 June 2014 21:56:37 UTC-4, K leo wrote: Thanks very much for the guide. I need to iterate in multiple dimensions. The example below is for 2 dimensions. Could anyone help making it simpler - in ways of recursions perhaps? l = [1:3] state = zeros(Int, 2) II = zeros(Int, 2) state[1] = start(l) while !done(l, state[1]) II[1], state[1] = next(l, state[1]) state[2] = start(l) while !done(l, state[2]) II[2], state[2] = next(l, state[2]) println(II) end end
Re: [julia-users] packaging parameters for functions revisited
Thanks very much for the summary. It is very interesting that assignFromArray is much faster than indexedArray. Can anyone explain why? On 05/30/2014 05:42 PM, Jon Norberg wrote: There have been several posts about this, so I tried to compile what I could find to compare speed and pretty coding: http://nbviewer.ipython.org/urls/dl.dropboxusercontent.com/u/38371278/Function%20parms%20passing%20speed%20test.ipynb Best speed is assigning values or variables inside the function Second best is reassigning parameters from array for each parameter. The @pack/@unpack macro also is pretty fast and much prettier Third best is separate parameters and global assignment (longer function call code if many parameters or/and just no no to use global?) Slowest is using indexed array as parameters in function (but this is ugly to read) and immutable types So I am wondering, did I miss any that improve speed/prettiness? Best, Jon
[julia-users] 2 sessions freeze up machine
I ran 2 julia programs each with a single CPU at the same time on a machine with 8 CPU's. After sometime (while the programs are running), the machine freezes - no mouse or keyboard responses. It happened a few time this morning. This seems just happened to the newly built versions. It was OK weeks ago. $ julia _ _ _ _(_)_ | A fresh approach to technical computing (_) | (_) (_)| Documentation: http://docs.julialang.org _ _ _| |_ __ _ | Type help() to list help topics | | | | | | |/ _` | | | | |_| | | | (_| | | Version 0.3.0-prerelease+3327 (2014-05-29 16:25 UTC) _/ |\__'_|_|_|\__'_| | Commit aa6113e* (1 day old master) |__/ | x86_64-linux-gnu
Re: [julia-users] 2 sessions freeze up machine
I should say that they are run separately at about the same time. The two have no communications, but share some pieces of codes. Just some simple computations going through some arrays. Some linear algebra but not using OpenBLAS. As I said, they ran OK weeks ago. I wonder if it has to do with the shared libraries that julia started to use recently. On 05/31/2014 11:43 AM, Isaiah Norton wrote: It will be helpful to know what you are running. Linear algebra operations via OpenBLAS can use multiple threads. On Fri, May 30, 2014 at 11:38 PM, cnbiz850 cnbiz...@gmail.com mailto:cnbiz...@gmail.com wrote: I ran 2 julia programs each with a single CPU at the same time on a machine with 8 CPU's. After sometime (while the programs are running), the machine freezes - no mouse or keyboard responses. It happened a few time this morning. This seems just happened to the newly built versions. It was OK weeks ago. $ julia _ _ _ _(_)_ | A fresh approach to technical computing (_) | (_) (_)| Documentation: http://docs.julialang.org _ _ _| |_ __ _ | Type help() to list help topics | | | | | | |/ _` | | | | |_| | | | (_| | | Version 0.3.0-prerelease+3327 (2014-05-29 16:25 UTC) _/ |\__'_|_|_|\__'_| | Commit aa6113e* (1 day old master) |__/ | x86_64-linux-gnu
[julia-users] performance of multiple julia sessions degrade
I ran 2 functions in 2 separate julia sessions, each using a single CPU. I found the processes' speed reduced to nearly half. Would anyone explain/confirm?
Re: [julia-users] performance of multiple julia sessions degrade
I guess I was mistaken, sorry. I print out time elapsed every 1 loops. The drop of speed I noticed might be due to the fact that some loops are more costly than others, not that 2 processes slow down. On 05/14/2014 01:17 PM, Elliot Saba wrote: Can you be a little more specific about what happened? Please share your hardware information, as well as the code you were running. On Tue, May 13, 2014 at 8:48 PM, cnbiz850 cnbiz...@gmail.com mailto:cnbiz...@gmail.com wrote: I ran 2 functions in 2 separate julia sessions, each using a single CPU. I found the processes' speed reduced to nearly half. Would anyone explain/confirm?
[julia-users] array element assignment very expensive in profile
Profile shows the two lines in the function being very expensive. Is
there anything inappropriate? Any way to improve?
function NoUpdate(data::Data)
data.cum[data.i] = data.cum[data.i-1]
data.i += 1
end
type Data
cum::Array{Float32,1}
i::Int32
...
end
Re: [julia-users] array element assignment very expensive in profile
Thanks for the response.
It is called in a loop. The function profiled is exactly as I showed
here. The profile section is as follows:
6449 ...ies/Gen13.jl; GenMC13; line: 176
4751 ...es/Tools.jl; NoUpdate; line: 224
829 ...es/Tools.jl; NoUpdate; line: 225
On 05/12/2014 10:14 PM, Kevin Squire wrote:
There's nothing specifically wrong with those two lines, but it's a
little hard to guess how you're using them. Are you calling the
function once, or in a loop? Is this version of the function
identical to the one you profiled, or was it cut down to be minimal?
if you provide more context, it's more likely someone could help you.
Cheers, Kevin
On Monday, May 12, 2014, cnbiz850 cnbiz...@gmail.com
mailto:cnbiz...@gmail.com wrote:
Profile shows the two lines in the function being very expensive.
Is there anything inappropriate? Any way to improve?
function NoUpdate(data::Data)
data.cum[data.i] = data.cum[data.i-1]
data.i += 1
end
type Data
cum::Array{Float32,1}
i::Int32
...
end
Re: [julia-users] array element assignment very expensive in profile
I am on 64bits Ubuntu. Should I better not use type 32 (Float32, Int32
etc.) on 64bit system?
On 05/12/2014 10:23 PM, Tim Holy wrote:
Are you on 32 bit or 64 bit? If 64, an Int32 +/- 1 generates an Int64. Why not
just declare i to be an Int?
--Tim
On Monday, May 12, 2014 09:53:50 PM cnbiz850 wrote:
Profile shows the two lines in the function being very expensive. Is
there anything inappropriate? Any way to improve?
function NoUpdate(data::Data)
data.cum[data.i] = data.cum[data.i-1]
data.i += 1
end
type Data
cum::Array{Float32,1}
i::Int32
...
end
Re: [julia-users] readcsv returns Array{T, 1}
I hope this is related.
Why isn't part of a row of Array{T, 2} of Array{T, 1}? Consider vec1 in
the following example.
df = readcsv(fname)
vec1 = df[3, 1:4]
Re: [julia-users] possible to forgo new in constructor
Thanks. This is a lot better in my mind because it gets rid of the trouble associated with matching the orders of the fields, which can be a big problem with many fields. I wonder what you mean by constructing incomplete objects gratuitously is a bad idea. On 05/11/2014 05:43 AM, Stefan Karpinski wrote: If you want, you can write type AA aa bb function AA() this = new() this.aa = 1 this.bb = 2 this end end But that seems like a lot more typing and constructing incomplete objects gratuitously is a bad idea, so I wouldn't recommend it.
[julia-users] question on performance
I tried to use comprehension in loops but found it somehow slower. In the following example, the loop in first code is slower than in the second. Would anyone please explain why? === function ffcombs() [Int8[i1,i2] for i1 in II, i2 in II] end combs = ffcombs() ii = zeros(Int8,2) for ii in combs ... end == for i1 in II, i2 in II ... end
Re: [julia-users] getting readtable to work
With Julia 0.3, readtable works.
On 05/10/2014 12:38 AM, Dustin Lee wrote:
I'm getting the following when trying to create a dataframe. I'd
appreciate some tips on how to troubleshoot this.
julia Julia Version 0.2.1
Commit e44b593905 (2014-01-30 13:47 UTC)
Platform Info:
System: Linux (i686-linux-gnu)
WORD_SIZE: 32
BLAS: libopenblas (NO_LAPACK NO_LAPACKE DYNAMIC_ARCH NO_AFFINITY)
LAPACK: liblapack.so.3
LIBM: libopenlibm
julia using DataFrames
julia outcomes = readtable(outcome-of-care-measures.csv)
ERROR: no method
readtable!(ParsedCSV,IOStream,Int64,ParseOptions{ASCIIString,UTF8String})
in readtable at /home/dlee/.julia/v0.2/DataFrames/src/io.jl:595
[julia-users] possible to forgo new in constructor
As in the following example, new(aa,bb) is very redundant from coding point of view. Since all fields are already declared and listed in the type definition, is it possible not to list them again with the new statement? The new statement can be very troublesome when the type has many fields. = type AA aa bb function AA() aa=1 bb=2 new(aa,bb) end end
Re: [julia-users] possible to forgo new in constructor
I meant having the inner constructor but having no need to write the new statement. Isn't the purpose of the new statement implied by the constructor already? On 05/10/2014 03:45 AM, Isaiah Norton wrote: Yes, if no inner constructor is provided, the default constructor is based on fields. So type AA aa::Int bb::Float64 end is valid (and common). On Fri, May 9, 2014 at 2:32 PM, cnbiz850 cnbiz...@gmail.com mailto:cnbiz...@gmail.com wrote: As in the following example, new(aa,bb) is very redundant from coding point of view. Since all fields are already declared and listed in the type definition, is it possible not to list them again with the new statement? The new statement can be very troublesome when the type has many fields. = type AA aa bb function AA() aa=1 bb=2 new(aa,bb) end end
[julia-users] invalid redefinition of constant MyType
I defined a composite type MyType. But when I modified it and tried to rerun a code that uses it, I got error: invalid redefinition of constant MyType. How can I avoid that?
[julia-users] difference between inside and outside constructors
Would anyone explain the differences between the following two ways of defining a composite type? = type AA aa bb function AA() aa=1 bb=2 new(aa,bb) end end type BB aa bb end function BB() aa=1 bb=2 return BB(aa,bb) end
Re: [julia-users] Question about 'dot' notation (and max/maximum)
My question is if x + A does not make sense in any way other than x .+ A, then why introduce .+ at all since + means intuitively .+ and is simpler? On 05/02/2014 09:55 PM, Hans W Borchers wrote: julia 5 + x WARNING: x::Number + A::Array is deprecated, use x .+ A instead.
Re: [julia-users] Rename column names in a DataFrames
DataFrames is a package I have been battling with recently. I must admit that getting a good knowledge about it is not easy, surely I hope that is different for other people. But after going through a lot of digging - searching the web, asking questions either here or at the issues with the package, and looking into the source code, I found it a powerful package capable of many features of a spreadsheet program. On 05/04/2014 09:08 PM, Milan Bouchet-Valat wrote: Le dimanche 04 mai 2014 à 08:25 -0400, Harlan Harris a écrit : Also, Andreas, the version of the docs you're looking at are extremely old. DataFrames.jl was moved to the JuliaStats organization GitHub account something like a year ago. How about removing the old documentation, or at least adding a warning there? Regards
Re: [julia-users] What editor/environment do you use when developing in Julia?
On Linux, gedit is great. The julia plugin works really well, with auto-completion. On 05/05/2014 02:10 AM, Aerlinger wrote: I'm using vim for the most part but was hoping to get a feel on what other people are using or if there are good alternatives out there. I've tried Julia Studio but it still seems a little too young feature-wise to be usable at this point.
[julia-users] Julia Tutorials
Just found this page with tutorials on a few packages. The one I found quite helpful, even though a little old, is on DataFrames, much more helpful than DataFrames's original documentation. https://github.com/JuliaLang/julia-tutorial
Re: [julia-users] Julia Tutorials
Well, Julia is easier to understand than English for sure;-) I just found it easier to get to know how to do what I needed to do. I have been through the document a few times, but didn't get much sense on how to access rows, find duplicate rows, delete rows, and etc. Adding on top of the frustration, the document is somewhat dated and includes many examples that are deprecated. Moreover, it does not list out too many available functions. On 05/01/2014 02:14 PM, John Myles White wrote: What makes the tutorial more helpful? The absence of English text? — John On Apr 30, 2014, at 11:04 PM, cnbiz850 cnbiz...@gmail.com wrote: Just found this page with tutorials on a few packages. The one I found quite helpful, even though a little old, is on DataFrames, much more helpful than DataFrames's original documentation. https://github.com/JuliaLang/julia-tutorial
Re: [julia-users] Bug or feature? Array{Number} squared gives Array{Any}
I got a sense that Any is widely misused and mishandled in Julia. It requires some cleanup. Anyone agree? On 04/30/2014 07:41 PM, Ariel Keselman wrote: see simplified behavior below: https://lh4.googleusercontent.com/-buanLj1oJlU/U2DhZ4Fo2XI/HS4/xC8WkdiahEM/s1600/Capture1.PNG
[julia-users] question about DataFrames package
My question is what is a symbol as in the following warning message?
=
julia df = DataFrame(A = 1:10, B = 2:2:20)
10x2 DataFrame
|---|||
| Row # | A | B |
| 1 | 1 | 2 |
| 2 | 2 | 4 |
| 3 | 3 | 6 |
| 4 | 4 | 8 |
| 5 | 5 | 10 |
| 6 | 6 | 12 |
| 7 | 7 | 14 |
| 8 | 8 | 16 |
| 9 | 9 | 18 |
| 10| 10 | 20 |
julia julia df[A]
WARNING: indexing DataFrames with strings is deprecated; use symbols instead
in depwarn at deprecated.jl:36
in getindex at ~/.julia/DataFrames/src/deprecated.jl:107
10-element DataArray{Int64,1}:
1
2
3
4
5
6
7
8
9
10
[julia-users] Anyone created MIME type for julia files?
Care to share?
Re: [julia-users] Re: Help me optimize Stochastic Gradient Descent of Least Squares Error
That is a great tip, thanks. I am having similar issues. I had the program in a file and run it with include(prog.jl) at the julia prompt. It used to take 12 seconds per 1 loops. Now Putting it into a function and also changed some variables to const, I got it down to 3 seconds per 1 loops. Big improvement, but not as big as 70 - 1.5. Perhaps due to file IO in some of the loops? On 04/27/2014 02:07 PM, Elliot Saba wrote: Hey there Freddy. The first thing you can do to speed up your code is to throw it inside of a function. Simply replacing your first line (which is begin) with function domytest() speeds up your code significantly. I get a runtime of about 1.5 seconds from running the function versus ~70 seconds from running the original code. I believe the reason behind this is because outside of a function, all of these variables are treated as global variables, which cannot have the same assumptions of type-stability that local variables can have, which slows down computation significantly. See this page http://julia.readthedocs.org/en/latest/manual/performance-tips/ for more info, and other performance tips. -E
[julia-users] help with combined for statement
for ff[1] in factors, ff[2] in factors, ff[3] in factors, ff[4] in factors, ff[5] in factors, ff[6] in factors, ff[7] in factors, ff[8] in factors, ff[9] in factors To simplify the above, I tried the following but it didn't work: for ff[1:9] in factors Is there a similar simple way to do?
Re: [julia-users] julia nightlies current version
I think you are running Xubuntu Raring, which reached end of life, and so they stopped building nightly for that OS. I am on Trusty and am getting the nightly for Saucy. On 04/23/2014 06:26 PM, Földes László wrote: Is the Julia nightlies update every day as it used to do around January/February? I don't receive updates for a long time now, and I want to investigate whether it is a failed Xubuntu upgrade that killed the Sources, or the package really don't update. Thanks versioninfo() Julia Version 0.3.0-prerelease Platform Info: System: Linux (i686-linux-gnu) CPU: Intel(R) Core(TM) i5-3320M CPU @ 2.60GHz WORD_SIZE: 32 BLAS: libblas.so.3 LAPACK: liblapack.so.3 LIBM: libopenlibm
[julia-users] help with using multiple cores
Copied the following test code from the online documentation. When tried to run it, I got the errors. Any guidance please? == a = randn(1000) @parallel (+) for i=1:10 f(a[randi(end)]) end == $ julia -p 4 _ _ _(_)_ | A fresh approach to technical computing (_) | (_) (_)| Documentation: http://docs.julialang.org _ _ _| |_ __ _ | Type help() to list help topics | | | | | | |/ _` | | | | |_| | | | (_| | | Version 0.3.0-prerelease _/ |\__'_|_|_|\__'_| | Official http://julialang.org release |__/ | x86_64-linux-gnu julia include(ParallelTest.jl) exception on 2: exception on 4: ERROR: ERROR: ff not defined not defined in in anonymousanonymous at at no fileno file::33 in in anonymousanonymous at at multi.jlmulti.jl::12631263 in in anonymousanonymous at at multi.jlmulti.jl::840840 in in run_work_thunkrun_work_thunk at at multi.jlmulti.jl::613613 in in run_work_thunk at run_work_thunk at multi.jl:multi.jl:622622 in in anonymousanonymous at at task.jltask.jl::66 ERROR: no method +(UndefVarError, UndefVarError) in mr_pairwise at reduce.jl:536 in mapreduce at reduce.jl:548 in preduce at multi.jl:1403 in include at boot.jl:244 while loading ~/Coding/Julia/ParallelTest.jl, in expression starting on line 1477
[julia-users] Re: help with using multiple cores
Sorry, the error messages must have to do with the undefined f. It works with the folowing. So I guess simply adding @parallel (+) on a for loop can then realize using multiple cores? === nheads = @parallel (+) for i=1:2 int(randbool()) end === On 04/19/2014 10:32 PM, cnbiz850 wrote: Copied the following test code from the online documentation. When tried to run it, I got the errors. Any guidance please? == a = randn(1000) @parallel (+) for i=1:10 f(a[randi(end)]) end == $ julia -p 4 _ _ _(_)_ | A fresh approach to technical computing (_) | (_) (_)| Documentation: http://docs.julialang.org _ _ _| |_ __ _ | Type help() to list help topics | | | | | | |/ _` | | | | |_| | | | (_| | | Version 0.3.0-prerelease _/ |\__'_|_|_|\__'_| | Official http://julialang.org release |__/ | x86_64-linux-gnu julia include(ParallelTest.jl) exception on 2: exception on 4: ERROR: ERROR: ff not defined not defined in in anonymousanonymous at at no fileno file::33 in in anonymousanonymous at at multi.jlmulti.jl::12631263 in in anonymousanonymous at at multi.jlmulti.jl::840840 in in run_work_thunkrun_work_thunk at at multi.jlmulti.jl::613613 in in run_work_thunk at run_work_thunk at multi.jl:multi.jl:622622 in in anonymousanonymous at at task.jltask.jl::66 ERROR: no method +(UndefVarError, UndefVarError) in mr_pairwise at reduce.jl:536 in mapreduce at reduce.jl:548 in preduce at multi.jl:1403 in include at boot.jl:244 while loading ~/Coding/Julia/ParallelTest.jl, in expression starting on line 1477
[julia-users] Re: help with using multiple cores
I also tried the following code with pmap. It ran and seemed to run
with 4 processes as shown with 'top'. But using pmap with my own
function, I don't see it run with 4 processes. What can be wrong?
==
M = {rand(1000,1000) for i=1:10}
pmap(svd, M)
==
On 04/19/2014 10:38 PM, cnbiz850 wrote:
Sorry, the error messages must have to do with the undefined f. It
works with the folowing. So I guess simply adding @parallel (+) on a
for loop can then realize using multiple cores?
===
nheads = @parallel (+) for i=1:2
int(randbool())
end
===
On 04/19/2014 10:32 PM, cnbiz850 wrote:
Copied the following test code from the online documentation. When
tried to run it, I got the errors. Any guidance please?
==
a = randn(1000)
@parallel (+) for i=1:10
f(a[randi(end)])
end
==
$ julia -p 4
_ _ _(_)_ | A fresh approach to technical computing
(_) | (_) (_)| Documentation: http://docs.julialang.org
_ _ _| |_ __ _ | Type help() to list help topics
| | | | | | |/ _` | |
| | |_| | | | (_| | | Version 0.3.0-prerelease
_/ |\__'_|_|_|\__'_| | Official http://julialang.org release
|__/ | x86_64-linux-gnu
julia include(ParallelTest.jl)
exception on 2: exception on 4: ERROR: ERROR: ff not defined not defined
in in anonymousanonymous at at no fileno file::33
in in anonymousanonymous at at multi.jlmulti.jl::12631263
in in anonymousanonymous at at multi.jlmulti.jl::840840
in in run_work_thunkrun_work_thunk at at multi.jlmulti.jl::613613
in in run_work_thunk at run_work_thunk at multi.jl:multi.jl:622622
in in anonymousanonymous at at task.jltask.jl::66
ERROR: no method +(UndefVarError, UndefVarError)
in mr_pairwise at reduce.jl:536
in mapreduce at reduce.jl:548
in preduce at multi.jl:1403
in include at boot.jl:244
while loading ~/Coding/Julia/ParallelTest.jl, in expression starting
on line 1477
[julia-users] line continuation
Searched but didn't find an answer. Does Julia allow statement to continue on the next line?
Re: [julia-users] line continuation
Thanks for the answer. I tested previously this but it did not work: if ab bc cd de ef But now this works: if ab bc cd de ef So the got to be on the end of the first for it to know that the line is not finished. On 04/17/2014 06:25 AM, Stefan Karpinski wrote: If the expression is incomplete, continuation is automatic. There is no explicit continuation syntax. On Apr 16, 2014, at 6:01 PM, cnbiz850 cnbiz...@gmail.com wrote: Searched but didn't find an answer. Does Julia allow statement to continue on the next line?
Re: [julia-users] julia installation on Ubuntu
Sounds like you have some broken packages in Ubuntu. I would open Synaptic to resolve the broken packages first. On 04/16/2014 06:17 AM, Stéphane Laurent wrote: Hi, I have just tried to install Julia but typing julia as a command line does not run anything (command not found). I have followed the following steps: / sudo add-apt-repository ppa:staticfloat/juliareleases/ / / / sudo apt-get update/ / / / sudo apt-get install julia/ I got a problem at the second step : /$ sudo apt-get update/ /.../ /Hit http://www.openprinting.org lsb3.2/contrib Translation-en / /Fetched 4,461 kB in 28s (155 kB/s) / /Reading package lists... Done/ /W: GPG error: http://cran.rstudio.com precise/ Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 51716619E084DAB9/ and at the third step : /$ sudo apt-get install julia/ /Reading package lists... Done/ /Building dependency tree / /Reading state information... Done/ /Some packages could not be installed. This may mean that you have/ /requested an impossible situation or if you are using the unstable/ /distribution that some required packages have not yet been created/ /or been moved out of Incoming./ /The following information may help to resolve the situation:/ / / /The following packages have unmet dependencies:/ / julia : Depends: libopenblas-base but it is not going to be installed or/ / libblas3 but it is not installable or/ / libatlas3-base but it is not installable/ / Depends: liblapack3 but it is not going to be installed or/ / libatlas3-base but it is not installable/ / Depends: libcholmod1.7.1 but it is not going to be installed/ / Depends: libumfpack5.4.0 but it is not going to be installed/ / Depends: libarpack2 but it is not going to be installed/ /E: Unable to correct problems, you have held broken packages./ What should I do ? Please consider I'm a newbie in Linux (I don't even know what sudo means, I'm only copying-pasting some instructions).
[julia-users] easy way to print elegantly
julia println(aa, , bb) 1.5231071779744345 33.97688693695 Is there a simple way to print 1.52 33.97 perhaps without the C format?
Re: [julia-users] easy way to print elegantly
Thank you. I am hoping if we could do something like this: println(aa[1,5], , bb[1,5]) hopefully one can access part of strings that way. On 04/08/2014 10:05 AM, Stefan Karpinski wrote: julia @printf(%.2f %.2f\n, aa, bb) 1.52 33.98 Note the rounding of bb. On Mon, Apr 7, 2014 at 9:35 PM, cnbiz850 cnbiz...@gmail.com mailto:cnbiz...@gmail.com wrote: julia println(aa, , bb) 1.5231071779744345 33.97688693695 Is there a simple way to print 1.52 33.97 perhaps without the C format?
[julia-users] how to determine a variable is a number
typeof(var) gives something too specific, like Int16, Float32, etc. Is there a convenient way to determine if var is a number or something else (string)? I tried isreal(var), but it gives an error in case var is not a number.
[julia-users] Re: how to determine a variable is a number
OK, just found this. typeof(var) : Number On 03/24/2014 09:20 AM, cnbiz850 wrote: typeof(var) gives something too specific, like Int16, Float32, etc. Is there a convenient way to determine if var is a number or something else (string)? I tried isreal(var), but it gives an error in case var is not a number.
Re: [julia-users] Re: how to determine a variable is a number
Use to determine something read in from a file. On 03/24/2014 09:30 AM, Collin Glass wrote: Hmm.. What's your use case? I mean you could just whip up a quick function isnum that returns true if typeof is any of the collection of formats. On Sunday, March 23, 2014 9:20:51 PM UTC-4, K leo wrote: typeof(var) gives something too specific, like Int16, Float32, etc. Is there a convenient way to determine if var is a number or something else (string)? I tried isreal(var), but it gives an error in case var is not a number.
Re: [julia-users] Simple speed test
On Ubuntu Trusty 64bits with i7 laptop, my result as follows. Notice the difference from Jason's julia @elapsed begin x = 0 for n = 1:1 x += 1 end x end 4.576735929 julia function g() x = 0 for n = 1:1 x += 1 end return x end g (generic function with 1 method) julia @elapsed g() 0.105158858 On 03/23/2014 12:18 PM, Jason Merrill wrote: This is not a small nit that John is picking: julia @elapsed begin x = 0 for n = 1:1 x += 1 end x end 7.333491931 julia function g() x = 0 for n = 1:1 x += 1 end return x end g (generic function with 1 method) julia @elapsed g() 0.047755206 The second version makes you wonder what on earth PyPy is doing for a whole second ;-)
Re: [julia-users] Re: Not fun
Well, from this perspective, it makes sense why those strings should not be mutable. But from other perspectives, making strings immutable contradicts with how natural languages are used. For instance, after I said I am a professor, I want to say I am a scientist, or perhaps I change my mind and say I am a scholar. Perhaps the key here is that we make a distinction between string and word. It is totally understandable and reasonable that words are not mutable. But a string, as a sentence, should not be immutable. On 03/21/2014 09:09 PM, Ivar Nesje wrote: We try to be helpful, and answer the questions as asked. We also provide advice for improvements, if the question is likely to lead to a poor program. Julia gives you as a programmer lots of power, and if you don't follow advice, you might end up in trouble. If you change the internal representation of a string, you will run into trouble in some parts of Julia, because we assume that strings are immutable. If you never let other parts of Julia hold a reference to the string while you are manipulating it, you should be alright. eg. a = Dict() b = hello a[b] = 1 b.data[5] = 'a' will make the value in the dictionary inaccessible. julia a[b] ERROR: key not found: hella in getindex at dict.jl:586 julia a[hello] ERROR: key not found: hello in getindex at dict.jl:586 Ivar kl. 13:42:23 UTC+1 fredag 21. mars 2014 skrev Andreas Lobinger følgende: Hello colleagues, this conversation is covering one of the most dangerous things that you can do in SW engineering: - How can i do X? - This is not meant to be used. But i have a work around for you. You can be absolutely sure that this will propagate and be the new default way. (I'm cleaning up other people's code at the moment, not julia, but still...)
Re: [julia-users] Re: [First post] What IDE everyone uses?
That doesn't seem to work. I got the the follow: julia-studio-julia-0.3-compatibility/bin$ ./julia-studio.sh ./julia-studio.sh: 35: exec: ./JuliaStudio: not found On 03/19/2014 10:56 PM, Uwe Fechner wrote: Hi, Julia Studio for Julia 0.3beta is available here: https://github.com/forio/julia-studio/tree/julia-0.3-compatibility I would not use anything else. Regards: Uwe On Monday, March 17, 2014 6:14:51 AM UTC+1, K leo wrote: Hi everyone, I am new to Julia. JuliaStudio is broken for me with the new 0.3 nightly. But I discovered gedit is great with Julia. It even has code completion. Any other good environment?
[julia-users] [First post] What IDE everyone uses?
Hi everyone, I am new to Julia. JuliaStudio is broken for me with the new 0.3 nightly. But I discovered gedit is great with Julia. It even has code completion. Any other good environment?
