[julia-users] Re: for loop with multiple variables

Thanks :) On Tuesday, May 10, 2016 at 4:44:18 PM UTC+5:30, Lutfullah Tomak wrote: > > for (i,j)=zip(0:5,6:10) > println(i+j) > end > On Tuesday, May 10, 2016 at 2:02:41 PM UTC+3, Vishnu Raj wrote: >> >> What if the equivalent of the C code below >> for( i=0, j=6; i<=5, j <=10; i++, j++ )

[julia-users] Re: for loop with multiple variables

for (i,j)=zip(0:5,6:10) println(i+j) end On Tuesday, May 10, 2016 at 2:02:41 PM UTC+3, Vishnu Raj wrote: > > What if the equivalent of the C code below > for( i=0, j=6; i<=5, j <=10; i++, j++ ) print( "%d", i+j ); > in julia? >

Re: [julia-users] Re: For loop = or in?

Agreed with Tony. Having lots of ways to do the same thing is fine, as long as we had no other syntactical use for the `=`. Anyone want to support notation like: `for y = sin(_) in 1:10 ... end`? Probably not, so no big deal to keep both around. Also I just saw Tk's post with this great

Re: [julia-users] Re: For loop = or in?

+1 On Thursday, October 29, 2015 at 5:56:46 AM UTC-7, Tom Breloff wrote: > > Lets close the topic. Keep them both. > > On Thu, Oct 29, 2015 at 8:47 AM, feza > wrote: > >> My only problem with `=` vs `in` >> is that even the base julia code is inconsistent! Looking at one

Re: [julia-users] Re: For loop = or in?

1. Unless there is a single syntax, the topic will inevitably come up again and again. This does not necessarily mean that we need a single syntax, but this is a cost of the status quo (ie having both = and in) that has to be considered. 2. I think everyone said what they wanted to say. IMO it

Re: [julia-users] Re: For loop = or in?

Maybe I was not clear: having multiple syntaxes per se is not necessarily bad. What is somewhat inconvenient is that since there is no good reason for having multiple syntaxes, some newcomers to the language will be confused, and will ask about this from time to time. Eg this is how this thread

Re: [julia-users] Re: For loop = or in?

How is having multiple syntaxes for something automatically bad? I don't hear people complaining that for loops are redundant when you could just do while with a counter, or that enumerate is equivalent. Having style guidelines for base to say when one choice makes more sense than another is

Re: [julia-users] Re: For loop = or in?

Well then it's settled. Someone prepare a PR ;)

Re: [julia-users] Re: For loop = or in?

But that's true of just about every instance where there are multiple ways of doing things. vcat vs [;], for instance. In some cases, there are distinct reasons; in others, there's no functional difference, and it only exists for the purposes of making it easier to read, for instance. Like

Re: [julia-users] Re: For loop = or in?

My only problem with `=` vs `in` is that even the base julia code is inconsistent! Looking at one file ( I can't remember which now) it had both i = 1:nr and i in 1:n Again this was in the same file! Please tell me I am not being pedantic when I saw this and thought this must be fixed if even

Re: [julia-users] Re: For loop = or in?

Lets close the topic. Keep them both. On Thu, Oct 29, 2015 at 8:47 AM, feza wrote: > My only problem with `=` vs `in` > is that even the base julia code is inconsistent! Looking at one file ( I > can't remember which now) > it had both > i = 1:nr > and > i in 1:n > Again

[julia-users] Re: For loop = or in?

Hi, Before closing (this thread?), I would like to write one more thing. First, because I am not a native English speaker, it doesn't actually matter how 1:n etc "reads" (simply because I don't pronounce them in mind :) Second, when I started learning Julia half a year ago (sorry for a slow

Re: [julia-users] Re: For loop = or in?

Do we want to give up on this topic? Then we should do so in an earnest way and close the case with a clear message, ideally after establishing if we want to add a style recommendation about the use of ``=`` and ``in`` to http://docs.julialang.org/en/release-0.4/manual/style-guide/. Currently

Re: [julia-users] Re: For loop = or in?

> `=` better than `in`: `a = [ f(i,j,k) for i=1:p, j=1:q, k=1:r ]` Please note that I am not trying to claim "=" is better universally (i.e. for everyone) based on this example, because some people prefer more English like syntax for clarity of meaning (even when a bit longer). So anyway, it

Re: [julia-users] Re: For loop = or in?

See https://github.com/JuliaLang/julia/issues/8487 On Wednesday, October 28, 2015 at 10:16:37 AM UTC-4, Stefan Karpinski wrote: > > No, it's just a matter of changing the parser to accept that – and > convincing people that it's a good idea. > > On Wed, Oct 28, 2015 at 9:39 AM, DNF

Re: [julia-users] Re: For loop = or in?

I read 1:n that way. And even if I didn't, I prefer to think about a looping construct as "do this for each element in that collection" - and regardless of how I pronounce 1:n, I see it as a collection since it inherits AbstractArray. But I can also see how other mental models work for you.

[julia-users] Re: For loop = or in?

I'm with Tomas here - if anything this thread is testimony to the fact that both '=' and 'in' should be left in.

Re: [julia-users] Re: For loop = or in?

I have to agree with Stefan that this is turning into bikeshedding [1]. My personal bias is towards `in`, probably due to my many years of Python, but I am convinced that both keeping the current duality or picking one of them will not lead to a mental overload. In fact, in order for us to stop

Re: [julia-users] Re: For loop = or in?

Pontus, you're awesome. Technically the first commit here was merged 4 minutes before your post, but funny anyway: julia> mod(big"0xdfe0cc00e3ae91cd981d0b4243498f8321992fbc",10) 0 julia> mod(big"0xf8a4340548e7d6be31fede13cdc4e0f5f434f33f",10) 7 My opinion would be to leave it since Julia isn't

Re: [julia-users] Re: For loop = or in?

On Wednesday, October 28, 2015 at 9:51:10 AM UTC+1, Tamas Papp wrote: > > I am probably old-fashined, but I always prefer to stick to ASCII unless > there is a compelling reason. If I want something to stick out, I can > always customize Emacs to do it. > Well, both 'in' and '=' are ASCII,

[julia-users] Re: For loop = or in?

I think people grossly exaggerate the "mental cost" of having both = and in. It's really not that complicated, well explained in the docs and can never cause bugs. On the other hand the depreciation cost will big quite large, given it seems both are used 50/50. Plus the numerous complain posts

Re: [julia-users] Re: For loop = or in?

On Wed, Oct 28 2015, feza wrote: > But really this seems like a fundamental enough language construct that > there should be only one correct way; but on the other hand my brain > doesn't have a problem with `=` and it seems natural since I have been > using matlab for a

[julia-users] Re: For loop = or in?

You are right, of course. It's just one of those minor cosmetic things you fix in a pre-1.0 version, or then maybe never. And it's good not to have too many of those. Also for i ∈ 1:N just looks incredibly awesome. On Wednesday, October 28, 2015 at 1:38:57 PM UTC+1, STAR0SS wrote: > > I

Re: [julia-users] Re: For loop = or in?

On Wednesday, October 28, 2015 at 2:29:54 PM UTC+1, Stefan Karpinski wrote: > > I think we're getting into Parkinson's law territory here. First off, I > don't think this causes all that much confusion. Second, since this is pure > syntax involving a keyword no less, this is one of the easiest

[julia-users] Re: For loop = or in?

actually its more about simple confusion rather than mental cost @DNF. Starting out you either use = or in then you see some other code and they use something else and wonder, what is right, is one notation faster or better, what's going on? Of course, it's not the simplest thing to try and

Re: [julia-users] Re: For loop = or in?

I think we're getting into Parkinson's law territory here. First off, I don't think this causes all that much confusion. Second, since this is pure syntax involving a keyword no less, this is one of the easiest things to mechanically fix should we chose to do so in the future. On Wed, Oct 28,

Re: [julia-users] Re: For loop = or in?

On Wednesday, October 28, 2015 at 10:22:45 AM UTC+1, Glen O wrote: > > The thing is, it IS an assignment that's going on. In the case of a range, > especially, "for i=1:5" says "loop 5 times, with i=1, then i=2, then i=3, > then i=4, then i=5". "i' is being assigned to on each iteration. Think

Re: [julia-users] Re: For loop = or in?

No, it's just a matter of changing the parser to accept that – and convincing people that it's a good idea. On Wed, Oct 28, 2015 at 9:39 AM, DNF wrote: > On Wednesday, October 28, 2015 at 2:29:54 PM UTC+1, Stefan Karpinski wrote: >> >> I think we're getting into Parkinson's

Re: [julia-users] Re: For loop = or in?

My vote is for keeping '='. It is very readable for counters as is 'in' for other containers. Confusion? Considering the investment into learning all the new and powerful Julia language constructs, I don't see why exactly this elegant duality would be a problem for anyone. It is not even a

Re: [julia-users] Re: For loop = or in?

On Wednesday, October 28, 2015 at 8:56:44 AM UTC+1, DNF wrote: > > I don't think = and in represent an elegant duality. They seem a very odd > couple to me (even though I have been using = in Matlab for 15 years.) On > the other hand, = and ∈ do seem to offer an elegant duality, > Sorry, of

Re: [julia-users] Re: For loop = or in?

On Wednesday, October 28, 2015 at 7:56:54 AM UTC+1, Gabor wrote: > > Confusion? > Considering the investment into learning all the new and powerful Julia > language constructs, > I don't see why exactly this elegant duality would be a problem for anyone. > I don't think = and in represent an

Re: [julia-users] Re: For loop = or in?

On Wed, Oct 28 2015, DNF wrote: > On Wednesday, October 28, 2015 at 7:56:54 AM UTC+1, Gabor wrote: >> >> Confusion? >> Considering the investment into learning all the new and powerful Julia >> language constructs, >> I don't see why exactly this elegant duality would be a

Re: [julia-users] Re: For loop = or in?

The thing is, it IS an assignment that's going on. In the case of a range, especially, "for i=1:5" says "loop 5 times, with i=1, then i=2, then i=3, then i=4, then i=5". "i' is being assigned to on each iteration. Think of it this way - suppose you were using elementwise operations. You could

[julia-users] Re: For loop = or in?

Thank you. In that case I will happily stick with `in`. On Monday, October 26, 2015 at 8:43:22 PM UTC, Alireza Nejati wrote: > > There is no difference, as far as I know. > > '=' seems to be used more for explicit ranges (i = 1:5) and 'in' seems to > be used more for variables (i in mylist). But

Re: [julia-users] Re: For loop = or in?

+1 @Tom Breloff . I was confused about this when starting out. Comparing `for i in 1:3` vs `for i = 1:3`, even though I regularly use matlab if you think about it for `i = 1:10` doesn't really make a lot of sense. It would be nice if it was just one way as opposed to the confusion about

Re: [julia-users] Re: For loop = or in?

An alternative way to read it is "for x equals 1 through 5". It definitely makes sense for a range. And I don't think anyone has any difficulty intuitively understanding a for loop using =, even if "in" reads slightly better. Incidentally, it's not just Matlab that does it. Most variants of

Re: [julia-users] Re: For loop = or in?

"When calculating a Fibonacci number, we have to apply F_n=F_(n-1)+F_(n-2) repeatedly. So to find F_6, we apply the equation for n equals 3 through 6". Writing it as "for n in 3 through 6" or "for n in the range 3 through 6" wouldn't make nearly as much sense. As I said, for general iterables,

Re: [julia-users] Re: For loop = or in?

> > It definitely makes sense for a range. Sorry... gotta disagree... mathematical set notation is more appropriate, especially for scientific computing. This is coming from a former matlab user, btw, so it's not like I was confused by the syntax. The "for i = 1:5" syntax is actually more

Re: [julia-users] Re: For loop = or in?

Please, leave the '=' alone. It's very well as is. terça-feira, 27 de Outubro de 2015 às 18:20:19 UTC, FANG Colin escreveu: > > Julia tries to attract people from Python & R, which use `in`. As for > matlab, it is not a direct competitor. > > Anyway, I think we only need 1 of the 2. "There

RE: [julia-users] Re: For loop = or in?

ent: Tuesday, October 27, 2015 11:20 AM To: julia-users@googlegroups.com Subject: Re: [julia-users] Re: For loop = or in? Julia tries to attract people from Python & R, which use `in`. As for matlab, it is not a direct competitor. Anyway, I think we only need 1 of the 2. "There s

Re: [julia-users] Re: For loop = or in?

On Tuesday, October 27, 2015 at 4:56:12 PM UTC+1, Glen O wrote: > > Incidentally, it would be nice if ∈ could be used as another option - it's > just another way of saying "in", but it would look nicer in certain > mathematical contexts, and it's not like the symbol would be used in > another

Re: [julia-users] Re: For loop = or in?

On Tue, Oct 27, 2015 at 10:04 AM, Stefan Karpinski wrote: > My general approach is to only use = when the RHS is an explicit range, as > in `for i = 1:n`. For everything else I use `for i in v`. I would be ok > with dropping the = syntax at some point, but it seems pretty

Re: [julia-users] Re: For loop = or in?

As far as I can understand, Julia also seems trying to attract people from Matlab, because there are so many similarities in the syntax (.* and ./ etc) and the names of functions. Also I often see questions from Matlab users posted in StackOverflow. Their codes are rather Matlab-like, but it

Re: [julia-users] Re: For loop = or in?

It's harmless, sure, but I would prefer that everyone uses "in" exclusively so that there's one less thing to waste brainpower on. You don't say "for each x equals the range 1 to n", you say "for each x in the range 1 to n". I don't think "=" has a place here at all except to allow copy/pasting

Re: [julia-users] Re: For loop = or in?

My general approach is to only use = when the RHS is an explicit range, as in `for i = 1:n`. For everything else I use `for i in v`. I would be ok with dropping the = syntax at some point, but it seems pretty harmless to have it. On Tue, Oct 27, 2015 at 8:56 AM, FANG Colin

[julia-users] Re: For loop = or in?

There is no difference, as far as I know. '=' seems to be used more for explicit ranges (i = 1:5) and 'in' seems to be used more for variables (i in mylist). But using 'in' for everything is ok too. The '=' is there for familiarity with matlab. Remember that julia's syntax was in part

Re: [julia-users] Re: Parallel loop, what wroong ? Parallel is slower then normal

How many worker threads did you start? Can you make D a SharedArray or DArray? On Sat Jan 31 2015 at 10:55:51 AM Paul Analyst paul.anal...@mail.com wrote: Realy ? Is imposibly smoething like : take 1. column and copmute on 1. core, wihout waiting for end of 1. oparation take 2. column and

[julia-users] Re: Parallel loop, what wroong ? Parallel is slower then normal

Hi Paul, If D is allocated on the master, then Julia will need to pass D from the master to the workers. I'm guessing that this communication might be more expensive than the compute in your loops. It may be useful to take a look at distributed arrays in the parallel section of the Julia

Re: [julia-users] Re: Parallel loop, what wroong ? Parallel is slower then normal

Nash, big thx julia procs() 1-element Array{Int64,1}: 1 julia addprocs(7) 7-element Array{Any,1}: 2 3 4 5 6 7 8 Now is 3-4 times faster !!! Paul W dniu 2015-01-31 o 17:00, Jameson Nash pisze: How many worker threads did you start? Can you make D a SharedArray or DArray? On Sat Jan

Re: [julia-users] Re: Parallel loop, what wroong ? Parallel is slower then normal

Paul, until the threads branch gets merged, I recommend that you just accept the fact that you'll only have 1 core active for most operations. --Tim On Saturday, January 31, 2015 07:15:25 AM paul analyst wrote: Thx, but, no. For sparse matrix 10^5,10^4,0.002 is the same . Time for both whiles

[julia-users] Re: Parallel loop, what wroong ? Parallel is slower then normal

Thx, but, no. For sparse matrix 10^5,10^4,0.002 is the same . Time for both whiles is about 48 sek, only 11% o cores is used. I vave 8 cores, 7 sleeps:/ Paul W dniu sobota, 31 stycznia 2015 15:50:02 UTC+1 użytkownik Sam Kaplan napisał: Hi Paul, If D is allocated on the master, then Julia

[julia-users] Re: For Loop over set of vector names

Thanks for the tips! As an academic trying to move lots of code over from other languages my lack of knowledge in coding fundamentals is being exposed a bit. Alex On Sunday, September 7, 2014 3:03:01 PM UTC-7, Alex wrote: Hi Everyone, I've been having some trouble using a for loop to

[julia-users] Re: For Loop over set of vector names

EDIT: Sorry I forgot to add the output. julia n=5 5 julia for i in [foo,bar] x_$i=zeros(n,n) println(x_$i) end x_foo x_bar julia x_foo ERROR: x_foo not defined On Sunday, September 7, 2014 3:03:01 PM UTC-7, Alex wrote: Hi Everyone, I've been having some

[julia-users] Re: parallel loop with mutable types

You’ll need to evaluate the type definition on all processes, using the macro @everywhere type parms ... end *after* adding the worker process. If I do that, I can run your code without error. (However, k seems to be unchanged - you might have to use a DArray (distributed array) in

[julia-users] Re: parallel loop with mutable types

Great, solve first problem, thanks. using DArray though gives julia k=DArray(parms,20) exception on 2: ERROR: no method parms((UnitRange{Int64},)) in anonymous at multi.jl:840 in run_work_thunk at multi.jl:613 in run_work_thunk at multi.jl:622 in anonymous at task.jl:6 ERROR: assertion

[julia-users] Re: parallel loop with mutable types

also this works but does not change values in b @parallel for i=1:20 b[i]=k[i].r*k[i].K end I tried making b=DArray{Float64,1} or b=dones(20,1) but still values in b are not updated do I need to use spawn/fetch or pmap or something like this? Sorry, not fluent in parallel programming yet, but

[julia-users] Re: parallel loop with mutable types

pmap is probably useful here. Just to make sure, you *have* read the manual section on parallel programming http://docs.julialang.org/en/latest/manual/parallel-computing/, right? There's a lot of good stuff there =) //T On Tuesday, June 17, 2014 1:30:36 PM UTC+2, Jon Norberg wrote: also