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[GSoC] Boost.Multiprecision project
by Jyotesh Choudhari 22 Apr '13

22 Apr '13

Hello, My name is Jyotesh Choudhari and I am from India. I am pursuing my Masters in Computer Science and Technology from Indian Institute of Technology (IIT) Bombay. I went through the ideas page for GSoc 2013 and would like to work on Boost.Multiprecision (cpp_bin_float) project. Looking at the project description, I think I have understood what needs to be implemented in this project. I have also gone through the current code cpp_bin_float.hpp and I have understood some part of it. I want to know how detailed should my proposal be? What details should I include in my proposal? What should be the deliverables for the project? Thanking you. Regards, Jyotesh Choudhari

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[GSoC] Boost.multiprecision project
by Flórián Deé 22 Apr '13

22 Apr '13

Hello, I'm Florián Deé from Hungary, studying at Budapest University of Technology and Economics. I'm really interested in the Boost.Multiprecision project for GSoC 2013. A little background on myself, I'm an undergraduate software engineering student mostly into C and C++, with interests in low level programming and maths. I'm currently working on a project as an outsider member of the dorm's Coder team (a poker framework for AIs), and I'm also a "consultant" for students with their C/C++/Maths assignments (mostly calculus and linear algebra). As a result, I don't really have much free time till the exams, but I've planned, seen, written and debugged lots of different projects with different coding styles. Going through the project description, I think my skill set and interests would fit in nicely, with the exception of fast Fourier transforms, which I'm only mildly familiar with, but I'd gladly read any needed extra material till summer. So I kindly seek your guidance to help me go about my application for the GSoC 2013. Looking forward to your reply. Regards, Flórián

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[ublas] bugfix for matrix operation /
by Mario Mulansky 22 Apr '13

22 Apr '13

Hi, I wanted to add an elementwise divide operations for ublas matrices using operator / Unfortunately, there is operator/ defined for matrix and integral types which hides any other operator definition (matrix_expression.hpp l. 3388) and thus makes it impossible to add this functionality. I would like to add an enable_if statement there that checks if the second argument is convertible to matrix::value_type, as is done for other operators. Who would be responsible for this small change? I can provide the according patch, it's almost trivial. Mario

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[gsoc-2013] Physics Library Abstraction Layer
by Preston Hamlin 22 Apr '13

22 Apr '13

I am working on putting together a draft proposal for the project. Is there a preferred format desired? I was going to use a PDF since they are quite portable. I am somewhat confused as to the scope of the project, due to the previous posts in this thread. Is the library to be built upon a specific physics library (PhysX for instance) by utilizing existing code in the respective SDK to abstract away much of the object management? Or is it meant to be built from the ground up to create generic objects, which can then be translated into an arbitrary format for an existing library? Thank-you, -Preston

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library to support async/await pattern
by Valentin Milea 21 Apr '13

21 Apr '13

Is there interest for a coroutine-based library to make asynchronous APIs easier to deal with? Typically, for each task there is cruft: chaining callbacks, managing intermediate state and error codes (since exceptions don't fit this model). The code flow get inverted and becomes difficult to follow. Recent versions of F# and C# solve this problem. They implement an await operator that effectively suspends the executing method until a task completes. The compiler takes care of transforming subsequent code into a continuation. Everything runs on the main thread, with asynchronous methods spending most time awaiting. N3328 proposes resumable functions of this kind in C++. For an immediate solution we could leverage the Boost.Context/Coroutine library. The resulting code may look like this: try { task = do_a_async(...) // yield until task done task.await(); } catch (const some_exception& e) { // exceptions arrive in awaiting context } // normal code flow for (auto& task : tasks1) { task.await(); } taskAny = await_any(tasks2); taskAny.await(); ... There needs to be a representation for Awaitable tasks (similar to std::future but non-blocking). The other requirement is to have a Scheduler (run loop) in order to weave between coroutines. Benefits: - normal code flow: plain conditionals, loops, exceptions, RAII - algorithm state tracked on coroutine stack - async tasks are composable - any async API can be wrapped Cons: - must wrap async APIs (e.g. Boost.Asio) - needs std::exception_ptr to dispatch exceptions - stackful coroutines are sometimes difficult to debug I wrote an open-source library that does this: https://github.com/vmilea/CppAwait. It's far from Boost style but the concept looks sane. For a comparison between async patterns please see: https://github.com/vmilea/CppAwait/blob/master/Examples/ex_stockClient.cpp Making a Boost version would involve serious redesign. So is this worth pursuing? Thanks!

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Re: [boost] GSoC: More mentors?
by Christopher Kormanyos 21 Apr '13

21 Apr '13

> From Monday on students can apply for GSoC projects. > Mentors can already apply at > <https://google-melange.appspot.com/gsoc/homepage/google/gsoc2013>. > So far we have four possible mentors (for uBLAS, odeint, > graph and benchmark). Are there others who would like > to mentor? Then please pick a project from > <https://svn.boost.org/trac/boost/wiki/SoC2013> or propose > your own. > Thank you, Boris Hello, Christopher Kormanyos (who is me) just signed up as a potential mentor for the GSoC projects with Boost.Math and Boost.Multiprecision. We have already had contact with some good candidates. Thank you. Sincerely, Chris.

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GSOC - Boost.uBLAS interest
by deck léa 21 Apr '13

21 Apr '13

Hi Boost C++ Team ! My name is Lea Deck, I'm French and I study in fourth year in computer science (security in computer science), but I really like mathematics. So I look for projects that mix the two. I would be interesting in adding new mathematics properties to your uBLAS libraries, like Hadamard, Toeplitz and Block matrices, the generation of matrices, Strassen multiplications and possibly new algorithms. You also alluded to the Bernoulli numbers, but I don't see any mention in the list of new features. Is the project still available? If so, should its implementation also contain the Bernoulli polynomials? About the question of optimisation, I have some skills in Cuda (GPU) and OpenMP and so in parallelization of code. So I am able to produce a correct parallelized code. Also, my knowledge of C++ is beginning to spread to the use of C++11 ( including unordered structure map). One last question, what do you mean by "Pretty display" in your list of new features? My CV is available here <http://dla.immortal-pc.info/>. ( http://dla.immortal-pc.info/) Thank you for taking the time to read my e-mail, and I look forward to receive a response from you. With regards, DECK Léa

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[GSoC 2013] SVN?
by Vicente J. Botet Escriba 21 Apr '13

21 Apr '13

Hi, would all the GSoC projects be stored under SVN? Best, Vicente

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Qustion about GSOC Project
by Hardy Huang 20 Apr '13

20 Apr '13

Hi, there. I am a graduate student in Peking University. I have known Boost library for long. And I used it for several times. This year I wanted to get involved in GSOC, and I was happy when I see Boost in the list, it is my dream and it will be honor to contribute to such a powerful library. Since I am good at algorithm and data structure, knowing that there are some idea projects relative with algorithm and data structure, like radix sort, trie, I want to know something detail about the plan to develop algorithm and data structure. Thanks, I am expecting to receive some useful replies.

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Re: [boost] [config][mpl][type_traits][integer] BOOST_STATIC_CONSTANT should use constexpr
by Vicente J. Botet Escriba 20 Apr '13

20 Apr '13

Le 20/04/13 14:33, Vicente J. Botet Escriba a écrit : > Le 20/04/13 13:18, Antony Polukhin a écrit : >> 2013/4/20 John Maddock<boost.regex(a)virgin.net>: >> <...> >>> No that's correct as is: >>> >>> * if BOOST_NO_INCLASS_MEMBER_INITIALIZATION is defined, then the constant is >>> really an enum and there should be no out-of-line definitions. >>> * if BOOST_NO_INCLASS_MEMBER_INITIALIZATION is *not* defined, then the >>> constant *should* have the out-of-line definition in case it's address is >>> taken/used. >> Oh, now I see, thanks. >> >>> As for the original question, this is such a pervasive breaking change, I >>> think a new macro is inevitable I'm afraid :-( >> New macro will do exactly what the old macro did, but using C++11 >> feature. Code in all Boost libraries will be changed to use new macro. >> So the old macro will be required only for users code that use macro >> and attempts to take address of constant... >> >> To me, it looks less obscuring to have one macro and a note for users >> to use BOOST_CONSTEXPR_OR_CONST for out-of-line definition; than two >> macro (which one shall be used by default?) that do the same thing but >> very slightly differ in details. >> > Just to add some information about some uses > > grep -r BOOST_NO_INCLASS_MEMBER_INITIALIZATION * | wc -l > 113 > grep -r BOOST_STATIC_CONST * | wc -l > 6598 > The figures are a little bit better :) grep -r BOOST_STATIC_CONSTANT * | grep -v svn | wc -l 3030 grep -r BOOST_NO_INCLASS_MEMBER_INITIALIZATION * | grep -v svn | wc -l 57 Best, Vicente

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Trac: Add ref library
by Vicente J. Botet Escriba 20 Apr '13

20 Apr '13

Hi, Boost.Ref is not included as a library on the Trac system. Coul dit be added? Best, Vicente

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[log] Permission to merge to trunk
by Andrey Semashev 20 Apr '13

20 Apr '13

Hi, I'd like to ask for permission to merge Boost.Log v2 to Boost trunk. The library has passed the review back in 2010 and was provisionally accepted [1]. It has been reworked since then, and in a few recent posts I described the changes [2][3]. [1] http://lists.boost.org/boost-announce/2010/03/0256.php [2] http://thread.gmane.org/gmane.comp.lib.boost.devel/237748 [3] http://thread.gmane.org/gmane.comp.lib.boost.devel/239313

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Google Summer of Code - 2013: Boost C++ Libraries
by Ketan Akade 20 Apr '13

20 Apr '13

Hi, I am Ketan Akade, Graduate student at University of Southern California. I am majoring in Computer Science. I went through the project ideas of Boost C++ Libraries, and would like to work on it. I am particularly interested in the *Boost.uBLAS* project idea which is unifying representation of vector and matrices into a unique matrix class. Could you please let me know further details of the same? What steps should I take to start on this? PFA project proposal in which I have mentioned my academic and technical background. Thanks and regards, Ketan Akade Graduate Student, University of Southern California.

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[gsoc 2013] chrono::date
by Anurag Kalia 19 Apr '13

19 Apr '13

I saw the chrono::date library proposal in the ideas page of gsoc 2013. It already seems quite solid and fleshed out; I am confident that I have understood it and can carry it out. Here it is for reference: <http://tinyurl.com/ct4tc3m> I have a few questions though. 1) Is this proposal in its final stages? The Boost chrono library docs mention in appendices that they intend to implement it in later releases. What I want to ask is if I am allowed to propose changes in the library if I want to. For example, the proposal proposes that adding a year to 'Feb 29' (leap year) should result in 'Feb 28 of next year' (non-leap year). I tend to think this is counter-intuitive. The author already gives the excellent idea of using a syntax like "last/february/2013" which also covers the case of anniversaries falling on 'Feb 29' pretty well. Moreover, it is a pretty big assumption that a person would want to celebrate the 'Feb 29' anniversaries on 'Feb 28' and not on 'Mar 1'. Moreover, adding a month to '31 January' results in an invalid date (31 February). Why shouldn't we mirror the behaviour for years? We can just make a library function to cover this issue. In short, am I allowed to propose such changes? 2) How should I apply for gsoc now that I have found my area of interest? What is the last date of application? Shall I post a draft of my application here first for review before submitting it officially? Am I allowed to? 3) I have my final examinations scheduled during three weeks in the coming month of May after which I am totally free to pursue gsoc internship. Though I will use this time to research for design and implementations of other similar libraries, I would still need to channel much time into my examinations. How am I supposed to circumvent this conflict, given that I do have ample time to dedicate to my internship later on? Thanks.Anurag.

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[fusion] [range] Interest in unified functions
by Antony Polukhin 19 Apr '13

19 Apr '13

Hi, I was playing with Boost.Fusion and wrote this simple function: template <class Sequence> std::string stringize(const Sequence& seq) { std::string result; boost::fusion::for_each(seq, stringize_functor(result)); return result; } Which allows to convert many types to strings: boost::fusion::vector<cat, int, std::string> tup1(cat(), 0, "_0"); boost::tuple<cat, int, std::string> tup2(cat(), 0, "_0"); std::pair<cat, cat> cats; std::cout << stringize(tup1) << '\n' << stringize(tup2) << '\n' << stringize(cats) << '\n' But this example fails to convert the following : std::vector<cat> too_many_cats(20); All we need to do to allow conversions, is just add the following: #include <boost/range/algorithm/for_each.hpp> namespace boost { namespace fusion { template <typename Sequence, typename F> inline typename disable_if< traits::is_sequence<Sequence> , void >::type for_each(Sequence const& seq, F const& f) { ::boost::range::for_each(seq, f); } }} So now std::cout << stringize(too_many_cats) << '\n'; works and boost::fusion::for_each may work with any type, runtime length or compile time. We may also make a lot of other algorithms to make no difference between runtime and compile time classes: accumulate, find, find_if, count, all, none, begin, end, advance, distance, dereference, empty and others... The questions are: Is there interest in such features? Is there interest in adopting other algorithms and which ones? To what library shall those methods belong? -- Best regards, Antony Polukhin

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[signals2] Uncombined signal
by Ivan Le Lann 19 Apr '13

19 Apr '13

Hi, I have a project where I use boost::signals2 in the spirit of the "Signal Return Values (Advanced)" section of the tutorial. That is, I have signals roughly equivalent to : boost::signals2::signal<float (), maximum<float> > sig; // slots produce values accumulated by the combiner Problem comes when I want multiple combiners on the same slots. Especially combiners of different types : You need to duplicate signals, and you need your connection setup code to know about used combiners. IMHO, having a basic signal class with no combiner makes sense. Attached is a POC patch to version 1.50, to add to boost::signals2::signal the method : slot_call_range all (BOOST_SIGNALS2_SIGNATURE_FULL_ARGS(BOOST_SIGNALS2_NUM_ARGS)) const (in boost/signals2/detail/signal_template.hpp) >From there, I think one could use any algorithm/accumulator directly on the signal.all() result. Implementation left aside, any feedback on this ? Regards, Ivan

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GSoC project idea: Directory monitor for Boost.Asio (student wanted)
by Boris Schaeling 18 Apr '13

18 Apr '13

Here's another idea for a GSoC project: Turn the directory monitor from <http://www.highscore.de/boost/dir_monitor.zip> into a full-featured Boost.Asio extension. This includes understanding the source code of the existing directory monitor, getting familiar with Boost.Asio internals, enhancing the current interface, implementing the directory monitor on multiple operating systems, writing test cases and a documentation. This is a project which can be completed within a summer. It could be the right project for a student who is interested in Boost.Asio and wants to go through all steps from designing to documenting. Boris

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bug in boost::container ??
by Olaf Peter 18 Apr '13

18 Apr '13

Hi, the attached example confuses me, I've got: $ g++ -Wall boost_container_bug.cpp -o boost_container_bug && ./boost_container_bug (size=4 [1, 2, 3, 4, 0, 4]) $ LANG=en g++ --version g++ (GCC) 4.6.3 20120306 (Red Hat 4.6.3-2) Copyright (C) 2011 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Did I miss something or is it a bug? Thanks, Olaf

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[variant] Multivisitation patch
by Antony Polukhin 18 Apr '13

18 Apr '13

Hi, There is a ticket #8459 that adds boost::apply_visitor for arbitrary amount of arguments. If there will be no objections and comments, I'll commit it to trunk at the end of next week. -- Best regards, Antony Polukhin

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Using both boost 64 and 32 bit on Windows with CMake
by Klaim - Joël Lamotte 18 Apr '13

18 Apr '13

It appear that this mailing list don't accept cross messages so I'm posting a link to a discussion related to both boost and cmake. Basically I'm looking for guidance to help improving development of one application using boost in 64 and 32 bit modes by finding a way to make the FindBoost cmake module find the right binaries depending on either mode. Currently you have to specify an undocumented CMake variable manually to do this. See the full discussion: http://cmake.3232098.n2.nabble.com/boost-b2-Differenciate-32bit-and-64-bit-… Joel Lamotte

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Interested in working on a project for Boost
by Ganesh Prasad 18 Apr '13

18 Apr '13

I am a Student of 2nd Semester, B.Tech in Computer Science and Engineering from National Institute of Technology, Rourkela, India. I am interested in working on a project on “ Developing Data Structures and related algorithms for a generalized Matrix and Vector Class” for the Boost Libraries as a participant of GSoC. I have some experience in working on algorithm development in C++. And I am positive that I have pretty good knowledge in advanced C/C++.I have participated in various coding contests too. Though I am just a student of Second Semester, I can assure you that I'll be working up to the requirements and expectations. But I am new to this GSoC program. I need advice and help to go on with this project. So, requesting advice and help before I start discussing about my project ideas. :) -Ganesh Prasad

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[range] location of numeric algorithms
by Nathan Ridge 18 Apr '13

18 Apr '13

Hi, Is there any reason the numeric algorithms in Boost.Range (accumulate(), inner_product(), etc.) are located in boost/range/numeric.hpp rather than in files named boost/range/algorithm/<algorithm-name>.hpp like every other algorithm? I think it's confusing for users who expect the uniform file naming convention that Boost.Range applies to other algorithms, to apply to these ones too. Thanks, Nate

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[iostreams] Doc errors
by Richard Hadsell 18 Apr '13

18 Apr '13

I'm just starting to read the Boost.Iostreams documentation and found a couple of minor errors. Perhaps someone would like to make these trivial corrections to help other novices in the future. (1) 2.1.4. In the implementation of container_device::write, the block that writes remaining characters at the end of the container ("if (result < n) { ... }") should insert characters from 's + result', not from 's': "container_.insert(container_.end(), s + result, s + n);". (2) 2.1.4. In the implementation of container_device::seek, there are 3 uses of "ios_bas" instead of "ios_base". -- Dick Hadsell 203-992-6320 Fax: 203-992-6001 Reply-to: hadsell(a)blueskystudios.com Blue Sky Studioshttp://www.blueskystudios.com 1 American Lane, Greenwich, CT 06831-2560 Follow Blue Sky Studios on Facebook <http://www.facebook.com/BlueSkyStudios> and Twitter <http://twitter.com/#%21/blueskystudios>

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GOOGLE sUMMER OF CODE
by kashish jajodia 17 Apr '13

17 Apr '13

Dear sir/ma'am, I am really interested in your project(making libraries for C++) mentioned in google summer of code . I am good in algorithm and acquainted well with c++. What else do you require me to know for being a favourable candidate for this project??? & Do you Have any website/blog where I can get to know about the Boost libraries were included in C++11 standard library Thank you Yours kashish Jajodia B.tech computer science and engineering(second year) National Institute of technology , Trichy India

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About
by Hasit Bhatt 17 Apr '13

17 Apr '13

I am 3rd year student of Computer Science and Engineering from Institute Of Technology, Nirma University, Ahmedabad, one of the best Engineering colleges in Gujarat. I was going through GSoC ideas page and, as I like algorithms, I wish to work on algorithms. So, I just wanted to ask, how can I start working on it. ~ Hasit Bhatt

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