- Boost - lists.preview.boost.org

[voronoi]medial axis
by Louis Lavery 29 Aug '13

29 Aug '13

Hello, I'm hoping to use boost voronoi to construct the (internal) medial axis for closed shapes (with holes). I need to work out which vertices of the voronoi are inside, outside and on a boundary. So my first goal is to determine which vertices correspond to the ends of the input segments (boundary vertices). The way I do this at the moment, is to look at each edge and test if its source vertex, vertex0(), is equal to either end point of the segment contained by the edge's cell. (1) If it is then it's a boundary vertex otherwise it's not. Is that correct? (2) When comparing a vertex with an input point can I do an exact compare (==) or should I use a tolerance (epsilon)? Thanks, fuzzy.

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[RPC] Boost.Asio to write *concurrency ready* code
by Niall Douglas 28 Aug '13

28 Aug '13

On 27 Aug 2013 at 12:00, boost-request(a)lists.boost.org wrote: > I am *not sure* if anyone else has made such discovery, anyway, > comment is welcomed. What you have discovered is well known I am afraid. Indeed, proposed Boost.AFIO from this year's GSoC implements an asynchronous chainable closure execution engine on ASIO, and you can read documentation on how AFIO is equivalent to Google's and Microsoft's WG21 closure execution engine proposals here: https://ci.nedprod.com/job/Boost.AFIO%20Build%20Documentation/Boost.AF IO_Documentation/doc/html/afio/quickstart/closure_execution_engines/ho w_boost_afio_relates_to_exisit.html Paul did up a great matrix mapping APIs from those engines to AFIO equivalents at https://ci.nedprod.com/job/Boost.AFIO%20Build%20Documentation/Boost.AF IO_Documentation/doc/html/afio/quickstart/closure_execution_engines/ho w_boost_afio_relates_to_exisit/comparison_of_afio_with_other_cl.html and https://ci.nedprod.com/job/Boost.AFIO%20Build%20Documentation/Boost.AF IO_Documentation/doc/html/afio/quickstart/closure_execution_engines/ho w_boost_afio_relates_to_exisit/other_useful_comparisons.html. If we get time before GSoC closes, we may just go ahead and implement N3562 (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2013/n3562.pdf) using AFIO as it would be incredibly trivial to do so. However, the Boost community only voted closure execution support as third most important - they ranked directory change monitoring as highest, so that's what me and Paul are implementing now. (FYI to those interested, we're going to deliver some *seriously* performant directory monitoring. Testing of our direct kernel syscall based implementation suggests watching a 1 million file entry directory for changes will actually work on Windows, albeit pegging a 3.5Ghz 4 core machine at 75-85% of all CPUs. Linux sadly lacks the syscalls to match Windows, but a 100,000 entry directory may well work just fine) Niall -- Currently unemployed and looking for work. Work Portfolio: http://careers.stackoverflow.com/nialldouglas/

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Problem with boost::function on BlackBerry10
by Jens Weller 28 Aug '13

28 Aug '13

Hi boost Community, I've got a little problem with getting boost::function to run on BlackBerry10. So far, I was able to compile, link and run successfully when I do comment out some stuff in boost. Surely not the right way to do it, but proves to me that those lines are the problem, I'm looking for a fix, maybe a define I need to add to let this compile without changing boost headers. In total its only 3 errors, where 2 boil down to the same macro: /home/jweller/cpp/libraries/boost_1_54_0/boost/type_traits/detail/cv_traits_impl.hpp:25: Parenthesis/brace mismatch between #if and #else branches; using #if branch /home/jweller/cpp/libraries/boost_1_54_0/boost/type_traits/detail/cv_traits_impl.hpp:93: Excess closing brace in C++ code (or abuse of the C++ preprocessor) /home/jweller/cpp/libraries/boost_1_54_0/boost/type_traits/msvc/typeof.hpp:43: Ignoring definition of undeclared qualified class These two are in cv_traits_impl.hpp in boost/type_traits/detail/, caused by this line: #if !(BOOST_WORKAROUND(__GNUC__,== 3) && BOOST_WORKAROUND(__GNUC_MINOR__, <= 2)) This line is twice in this fiel, hence the 2 errors. qcc version is gcc 4.6.3. It looks to me like BOOST_WORKAROUND isn't doing the right thing here to me. The 2nd error is more strange. /home/jweller/cpp/libraries/boost_1_54_0/boost/type_traits/msvc/typeof.hpp:43: Ignoring definition of undeclared qualified class Somehow typeof.hpp of msvc is getting pulled in. I've tried also the from BlackBerry provided boost version from https://github.com/blackberry/Boost, which shows exact the same errors. And is the one I (cruely) patched currently. Commenting out the #if !(is < 3.2) resolves the problem, but msvc is still pulled in. Also commenting in this header the cause out lets it compile, but thats nothing then a bad workaround. Currently I have only build for the simulator, but the problem is most likely also existing for the device build chain. At least the first two errors might be caused by BOOST_WORKAROUND, maybe there is a value that isn't configured correctly on this platform. Also how do I get closer to the source of the msvc code being dragged in? So, question is, is there maybe a define to help boost getting digested by the qcc toolchain? kind regards, Jens Weller

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Migrating lists.boost.org
by DongInn Kim 28 Aug '13

28 Aug '13

Dear Boost community, I think it is time to move mailing lists and mail archives of lists.boost.org to the new server (wowbagger.crest.iu.edu) If it is not a bad time, can we migrate the services at 9am (E.T.) on Aug 28th? Date: Wednesday, Aug 28th, 2013 Time: 6:00am-8:00am Pacific US time 7:00am-9:00am Mountain US time 8:00am-10:00am Central US time 9:00am-11:00am Eastern US time 1:00pm-3:00pm GMT The following services may not be available during the migration. - Web services (e.g., http://lists.boost.org/) - Mailing lists: boost boost-announce boost-bugs boost-build boost-cmake boost-commit boost-docs boost-interest boost-mpi boost-test boost-testing boost-users geometry glas proto threads-devel ublas Please let me know if you have any questions or concerns about this migration. Regards, -- - DongInn

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Re: [boost] [cpo-proposal] presentation of the idea
by Santiago Tapia 28 Aug '13

28 Aug '13

>Date: Tue, 13 Aug 2013 07:42:03 -0500 >From: Larry Evans <cppljevans(a)suddenlink.net> >To: boost(a)lists.boost.org >Subject: Re: [boost] [cpo-proposal] presentation of the idea > > What if the class hierarchy is used to model a graph that > contains cycles. For example, something like a spirit grammar > where a non-terminal on the rhs of a non-terminals definition? I don't see any problem, as long as they fulfill the requirements of the classifier container, i.e. the objects to be inserted should be copyable and derived from the base class in the template argument of the classifier. > Wouldn't this require some sort of smart pointer or other > garbage collection method with the ability to collect cycles? > I don't think so, the classifier container should be able to replace any occurence of something like: vector< shared_ptr <base> > in almost in any circunstance. Beside, you could avoid virtual destructors because the classifier will destroy the object directly not from a base* pointer.

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Seeking "lazy piranha fedora 19 64 intel C++11" tester's contact info
by Jim Bell 27 Aug '13

27 Aug '13

Over on the boost-testing list, we're seeking the regression tester for "lazy piranha fedora 19 64 intel C++11". Please reply directly to me (off-list) if you have contact information for this person. Thanks, -Jim

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Modular boost directory structure
by Edward Diener 27 Aug '13

27 Aug '13

I am seeing at https://svn.boost.org/trac/boost/wiki/StartModDev that the modular Boost directory structure is: simple include boost simple twice.hpp test twice_test.cpp Jamfile.v2 doc // from the notes on the page index.html Is this the latest correct information ? I am asking because the original recommended structure was, as I understood it: simple boost simple twice.hpp libs simple test twice_test.cpp Jamfile.v2 doc html index.html I want to make sure I have this right before I modularize my sandbox libraries for git using the correct directory structure. BTW I have not been able to figure out how to add and move directories using git in a local copy. Instead I have just done so using the OS and git seems to figure it out but I have a feeling I have lost git history in doing so.

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[Boost.Log] SimpleEventLog configuration
by Pieter 27 Aug '13

27 Aug '13

LS, I am currently configuring my logging configuration using a property tree. When I include a simple_event_log_backend sink, it does not seem possible (yet) to configure an event type mapping to that sink from the property tree. The source code does contain the following comment: "For now we use only the default level mapping. Will add support for configuration later." so I guess my first question would be whether such support is indeed in the works? My second question would be whether it is possible to add such a mapping after the sink was created and added to the core. In the documentation an example is given where the mapping is done before the sink is added to the core: typedef sinks::synchronous_sink< sinks::simple_event_log_backend > sink_t; boost::shared_ptr< sink_t > sink(new sink_t()); sinks::event_log::custom_event_type_mapping< severity_level > mapping("Severity"); // . define mapping here . sink->locked_backend()->set_event_type_mapper(mapping); // Add the sink to the core logging::core::get()->add_sink(sink); but in the case at hand adding the sink happens behind the scenes when using the configuration utilities. It seems to me that there is no easy way to manipulate the sink in any way once it is added to the core (unless as in the example the shared_ptr to the sink is kept to access the sink maybe). Is this correct? Many thanks, Pieter P.s. BTW, in the section "Simplified library initialization tools" of the documentation Table 1.15 seems to miss a 'Format' parameter that I assume is still needed?

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doubts about python3 support
by Neal Becker 26 Aug '13

26 Aug '13

I'm building using: bjam -d+2 -j8 cxxflags='-march=native -Wno-unused-local-typedefs' -sHAVE_ICU=1 - sEXPAT_INCLUDE=/usr -sEXPAT_LIBPATH=/usr/lib64 --layout=tagged threading=single,multi link=shared stage In user-config.jam I added: using python : 3.3 : /usr/bin/python3 : /usr/include/python3.3m ; I wind up with stage/lib/libboost_python.so stage/lib/libboost_python3.so But AFAICT, they were build the same way. It's be nice if one was built against python2 and the other python3, but that doesn't appear to be true. AFAICT, both were built from the same sources (using /usr/include/python3.3m). What I'd like is to build both python2 and python3 from the same source tree, installing the final shared libs into the same destination dir. Right now I have 2 different source trees, and build switching the one line in user- config.jam.

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MSVC doesn't support "not"?!
by Daryle Walker 26 Aug '13

26 Aug '13

Just checked the regression testing pages. Most of the testing stations that reported fails for Boost.Rational have switched to pass since I've uploaded updates. Besides the stations that haven't run new tests, and the "teeks" team that run Clang tests although it seemingly isn't actually installed, the newly-run MSVC stations report fails. The old errors are gone, but the new error is: ..\libs\rational\test\rational_test.cpp(1012) : error C2065: 'not' : undeclared identifier ..\libs\rational\test\rational_test.cpp(1012) : error C2146: syntax error : missing ')' before identifier 'dummy' ..\libs\rational\test\rational_test.cpp(1012) : error C2059: syntax error : ')' This happens with MSVC 10.0 and 11.0. Hasn't "not" been an alternate symbol for "!" since C++98? I'll change it to "!", but that doesn't excuse not fixing it for 15 years! What happened? (I think some of the MSVC authors lurk here.) Daryle W.

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[config] BOOST_NO_SFINAE_EXPR and GCC 4.6.4
by Agustín K-ballo Bergé 26 Aug '13

26 Aug '13

According to this table http://gcc.gnu.org/projects/cxx0x.html, GCC supports "Solving the SFINAE problem for expressions" since 4.4. According to Boost.Config, it is since 4.5. The following test case works fine with 4.8.1, but fails miserably with 4.6.4: http://ideone.com/RzgXKM Errors include invalid conversion from X const* to X*, and use of non-member-ptr in member-ptr expression. GCC 4.7.3 (tested by zao at #boost) shows similar results: https://www.acc.umu.se/~zao/kbsfinae11.txt Should BOOST_NO_SFINAE_EXPR be adjusted according to the results of this test case? Regards, -- Agustín K-ballo Bergé.- http://talesofcpp.fusionfenix.com

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[RPC] Boost.Asio to write *concurrency ready* code
by microcai 26 Aug '13

26 Aug '13

Hi, boost experts! This is my first mail. Although I am not boost newbee, I am indeed new to the boost community. == I was using Boost.Asio for a long time, for *Async Network I/O*, but up till recently, I made an amazing discover that Boost.Asio is NOT ONLY a Network library, but indeed a very *general* toolkit for building concurrent algorithm. I made the first discover when my friend show up an concurrent sum ``` #include <iostream> #include <vector> #include <algorithm> #include <numeric> #include <future> template <typename RAIter> int parallel_sum(RAIter beg, RAIter end) { typename RAIter::difference_type len = end-beg; if(len < 1000) return std::accumulate(beg, end, 0); RAIter mid = beg + len/2; auto handle = std::async(std::launch::async, parallel_sum<RAIter>, mid, end); int sum = parallel_sum(beg, mid); return sum + handle.get(); } int main() { std::vector<int> v(10000, 1); std::cout << "The sum is " << parallel_sum(v.begin(), v.end()) << '\n'; } ``` Here the actual calculations are done async and concurrently. But, the problem remains: ** The total threads that this algorithm spawn is not predictable and not configurable. ** And that's why we will not like such algorithm altogether. Days later, when I am review an old code that was doing an *async directory walk through* , I soon discover an general *concurrency ready* algorithm that the number of threads utilized can be fully controlled. The code utilized *any number of threads that is doing io_service::run()* Here is the good old demo that uses recursive algorithm : ``` // this is sequential recursing version void hanoi_sync(int n, char A, char B, char C) { if (n == 1) { printf("Move disk %d from %c to %c\n", n, A, C); } else { hanoi_sync (n-1, A, C, B); printf("Move disk %d from %c to %c\n", n, A, C); hanoi_sync (n-1, B, A, C); } } ``` But with Boost.Asio, we turn it into parallelism algorithm: ``` // concurrent hannoi tower solver void hanoi_async(boost::asio::io_ service& io, int n, char A, char B, char C) { if (n == 1) { printf("thread id %d, Move disk %d from %c to %c\n", boost::this_thread::get_id(), n, A, C); } else { io.post(boost::bind(&hannoi_async, boost::ref(io), n-1, A, C, B)); printf("thread id %d, Move disk %d from %c to %c\n", boost::this_thread::get_id(), n, A, C); io.post(boost::bind(&hannoi_async, boost::ref(io), n-1, B, A, C)); } } ``` Thanks to the amazing io_service.post, we can now turing any (if not mostly) *recursing code* into *parallelism code*. And the threads that used by such *parallelism code* is fully controlled. If one thread is calling io_service::run(), then it is simple an async version of the sequential recursing one, if more that one thread is doing io_service::run(), then you know that the job is now run in parallel. And yet there needs only one place to control how may threads is used. Want it to be faster? spawn more threads to call io_service::run()! The code will *automatically* use all threads that you have allocated to Boost.Asio. I am *not sure* if anyone else has made such discovery, anyway, comment is welcomed.

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[type_triats] [move] is_copy_constructible<T> trait
by Antony Polukhin 26 Aug '13

26 Aug '13

Hi, I have an implementation of is_copy_constructible<T> trait. It works great with C++11, in C++03 it detects constructors assuming that if type is derived from boost::noncopyable or uses BOOST_MOVABLE_BUT_NOT_COPYABLE macro - it has no copy constructor. Questions are: * May I add that trait to trunk version of Boost.TypeTraits (with documentation and tests, as usual)? * May I or Boost.Move maintainer apply this patch to BOOST_MOVE_IMPL_NO_COPY_CTOR_OR_ASSIGN in boost/move/core.hpp : #ifdef BOOST_NO_CXX11_DELETED_FUNCTIONS #define BOOST_MOVE_IMPL_NO_COPY_CTOR_OR_ASSIGN(TYPE) \ private:\ TYPE(TYPE &);\ TYPE& operator=(TYPE &);\ + public: \ + typedef int boost_move_no_copy_constructor_or_assign; \ + private: \ // #else Why do I need this trait? Well, it allows to implement move_if_noexcept() that is required for circular_buffer and possibly for other containers. -- Best regards, Antony Polukhin

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[git] Some questions on Git transition
by Daryle Walker 26 Aug '13

26 Aug '13

* I see we have a GitHub account at https://github.com/boostorg, with repositories for each library. If we add a new library, and it has been Git-based, are we going to mirror it in the Boost account? That'll make sure if something happens to the original, we still have a last-known-good to work with. Would having all the libraries (or copies/mirrors) under the same account make scripts easier? What about non-Git libraries, will they be copied over? Would a bridge be used? (There's at least bridges for Git connecting to either Subversion or Mercurial.) * We currently ship all the libraries merged together as a single archive. Some package managers even provide the Boost libraries as a single item. When we go Git, is that still going to be in place (with the release managers doing some sort of merging script), or are we and every user going to move to doing several dozen downloads instead? (And everyone has to figure out how to use more than one Boost library at once.) * Are we eventually going to use something like http://nvie.com/posts/a-successful-git-branching-model/? If so, are we going to use that to script releases? (At release-time, grab the latest version of each library from their master branches, apply the merging script, run tests, then ship.) Daryle W.

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[release] How do you make a library update official?
by Daryle Walker 24 Aug '13

24 Aug '13

I just uploaded changes ([85417] and [85418]) to Boost.Rational that fix the two major problems showing up on the regression tests. How do I get them on the official distribution? I know we don't read off the SVN-trunk directly; there's some staging area first. (That's why the shippers occasionally declare a code freeze deadline.) I know we have a "release" branch, but I'm not sure that's still being used. I want to blaze ahead making tweaks to Boost.Rational, but not if you can't "make official" a non-HEAD change-set. Even if I miss the deadline for these other tweaks, I want the two I just already did to be in Boost 1.55. Daryle W.

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[admin] [svn] Boost.Commit list is not working
by Michel Morin 23 Aug '13

23 Aug '13

It seems that Boost.Commit mailing list has suspended for ten days. Regards, Michel

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How not to use auto-link?
by Daryle Walker 23 Aug '13

23 Aug '13

Recently, I've been using CodeLite for Windows to do my Boost work. I have it running a MinGW-builds version of GCC 4.8 by default. I've enabled CodeLite to use Visual C++, since I have a copy of the Express version and want to avoid missing MSVC-related errors in the future. After telling CodeLite where MSVC and its directories are, I ran "rational_test.cpp" by itself, which gave up a linking error for Boost.Test. The linker was looking for those fancy named libraries that I didn't automatically make since I usually include all the source files. (And I'm using Boost from a Subversion download instead of a fixed one.) I added the source files from Boost.Test and #defined BOOST_ALL_NO_LIB=1 from the project options. The project-make system was still looking for library files! (I don't recall if it was asking for the same library file.) As I already built those files while experimenting with the documentation system, I added that directory to the search list and everything worked. I thought defining BOOST_ALL_NO_LIB was sufficient to disable auto-linking. What did I mess up? Daryle W.

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[rational] Which way should std::numeric_limits::min go?
by Daryle Walker 23 Aug '13

23 Aug '13

The default implementation of a std::numeric_limits<T> instantiation is to have all static data member be set to static_cast<X>(0) and all the static member functions return T{}. When an instantiation is manually written, you're supposed to leave members for the types of numbers (integer vs. floating vs...) that you're NOT as in the unimplemented case. The static member function "min" has a defect. The function "denorm_min" returns the smallest positive value that can be represented (denormalized or not), and is implemented only for floating types. The function "lowest," new to C++11, returns the regular (i.e. not Infinity or NaN, etc.) value closest to negative-infinity. Lowest was introduced because for C++98/03, "min" returned "denorm_min" for the built-in floating types and "lowest" for built-in integer types! You can't get generic code out of that (without checking some more flags from numeric_limits). Which version of "min" should boost::rational take? I was think of "denorm_min," since I'll be implementing that. The built-in integer types use "lowest" for "min," but don't define the other one at all. Daryle W.

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concurrent_unordered_map request
by Eugene Gordienko 23 Aug '13

23 Aug '13

TBB and Microsoft have it. Why not to have it in boos?

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Reboot the boost web server machine
by DongInn Kim 22 Aug '13

22 Aug '13

Dear Boost community, There is a system upgrade on the boost web server machine and we need to reboot the machine to activate this change. Can we setup a schedule to reboot the server machine (wowbagger.crest.iu.edu) sometime this week? It would not take long to reboot the system (e.g., less than 10mins). If it does not cause too much disturbance, can we reboot the system at 9am tomorrow (Aug 22, 2013)? Regards, -- - DongInn

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[rational] Updated for fix; run tests
by Daryle Walker 22 Aug '13

22 Aug '13

Earlier today, I uploaded a fix a narrowing-conversion bug to boost::rational. (Ticket #5855, change-set [85418]) But I did another check-in first (change-set [85417]). The lower-numbered change represented a problem while fixing the ticket. C++11 adds two static members to std::numeric_limits. One of them, max_digits10, represents how many digits are needed to be printed to (near) guarantee text/binary conversion. Boost.Test uses it in its C++11 code, so it expects any version of numeric_limits to have it, which caused errors with Boost.Rational since that part of the test code hasn't been touched since it was written nearly 7 years ago! (There was a minor tweak over 5 years ago.) One advantage with Git is that I could have checked both changes separately. Here, for Subversion, I had to back out the second change, commit the first, then redo the second to get them recorded independently. I just did a quick look at our regression tests, and most of them involve one or both of the issues I just fixed. So can everyone do a test cycle sooner rather than later? (The "teeks99-08(e|f|g|h)-Ubnutu12.04-64" teams need to make sure Clang is installed and in the PATH.) Daryle W.

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[countertree] Concurrent set and map with random access iterators
by Francisco José Tapia 21 Aug '13

21 Aug '13

Hi this message is to announce the version 2.0 of the [countertree + suballocator] library. *This library provide a **concurrent** and **thread safe** implementation of the tree based data structures (**set, multiset, map** and **multimap**, plus a new data structure named **vector_tree**) with **random access iterators** and **access by position** like a vector. * *This permit to distribute the elements stored in the trees, between an arbitrary number of threads, identically as do with the vectors, making easy the design of **parallel algorithms** applied to the tree based data structures (as you can see in 2.3.- Examples<https://dl.dropboxusercontent.com/u/8437476/works/countertree_2.0/doc/P2.3_…>and 3.6.- Examples<https://dl.dropboxusercontent.com/u/8437476/works/countertree_2.0/doc/P3.6_…>) , and their use by the **multicore development tools** as **OpenMP, Threading Building Blocks ...* *You can find the documentation and the code in the GitHub* *https://github.com/fjtapia/countertree_2.0*<https://github.com/fjtapia/countertree_2.0> or you can see online in my dropbox page : https://dl.dropboxusercontent.com/u/8437476/works/countertree_2.0/index.html<https://dl.dropboxusercontent.com/u/8437476/works/countertree_2.0/doc/index…> If you prefer download a file with all the code and the documentation : https://github.com/fjtapia/countertree_2.0/blob/master/doc/countertree_2.0.… Perhaps the most interested parts of the documentation are : 1.4.- Concurrent version where explain the problems and new functions implemented 1.5.- Next improvements. Where explain the future development of the library and the concurrent algorithms 1 year ago I presented the request for the evaluation of the [countertree+ suballocator] version 1.0. The approval process is stopped due to the absence of review managers, and in the meanwhile I continued with the develop of this version 2.0. This version is big ( 50.000 lines ) and involve many programming areas ( algorithms, memory management, threads, locks ...) In the design process I must took many decision according my knowledge. I am sure there are many things to correct and improve. In the Boost community there are many people with knowledge and experience, and I trust they can help me in order to provide to the C++ users a good library. If you find an error, or you miss something in the library or have any idea or comment about it, please mail me and I will correct as soon as possible. Sincerely yours Francisco Tapia fjtapia(a)gmail.com *The Boost Formal Review Schedule is in http://www.boost.org/community/review_schedule.html where you can see the projects and their situation.

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Re: [boost] Request to allow contribution to Boost.Multiprecision cpp_bin_float
by Jyotesh Choudhari 20 Aug '13

20 Aug '13

Thanks for your replies. >>> I would like to contribute to the development of Boost.Multiprecision >>> cpp_bin_float library. Can I work on it? If yes, then how can I start? >> Hi Jyotesh, >> Paul Bristow, Chris Kormanyos and I have been discussing this off-list. >> There is a prototype implementation in the sandbox under the >> multiprecision.cpp_bin_float directory.? The current code is pretty much >> complete, but under-tested.? The binary-decimal and decimal-binary >> conversion routines used are also brain-dead and do not round correctly (I >> have a mostly working version that does this correctly on my hard drive, but >> it's not quite ready for commit yet). > Yes. But remember, Jyotesh, John has taken a different direction > than my original code in the sandbox. His implementation is in > a different directory, and it's likely that we will stick with John's > and leave my prototyping to rest. May I know which directory is this? >> So one of the things we need is for >> folks to try this out and see what breaks (or rather to see what they can >> break!). > Such as try some simple math functions or to use it in > conjunction with boost::math::constants for, say, computing > a few hundred digits of pi or log(2). OK. I will try these. >> Some of the std lib function test cases in the sandbox also fail >> currently as their error rates are too high.? Many are also much slower than >> say MPFR.? Chris, would have a better idea which most need working on. > Always important are square root, sine, cosine, and log. >> And finally, the implementation uses all integral arithmetic internally (via >> cpp_int), so one big improvement we need is for someone to write Karatsuba >> and FFT based multiplication routines for cpp_int (Karatsuba is probably the >> higher priority).? Oh and we have no docs yet. > Yes, very important, as this is a huge limitation of cpp_dec_float --- > at least for the digit hunters among us. :-) I will implement Karatsuba algorithm and let you know when I am finished. Thanks and Regards, Jyotesh Choudhari >> Anything there look like something you'd like to work on? >> Thanks for the interest, John. > Thanks for the interest. > Sincerely, Chris.

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Is there BOOST_ENABLE_IF macro now?
by TONGARI J 20 Aug '13

20 Aug '13

Hi folks, It's over 2 years since this post: http://boost.2283326.n4.nabble.com/New-powerful-way-to-use-enable-if-in-C-0… The macro looks sweet and I wonder if we have this macro in Boost in case that I missed it. Thanks.

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Re: [boost] [boost::spirit::basic_hold_any] needs non template operator=
by Hartmut Kaiser 20 Aug '13

20 Aug '13

> I found that hold_any template operator= is not used during assignment to > another hold_any (as intended by its developer). Instead compiler uses > self generated version of operator= which doesn't forward to assign(const > basic_hold_any&). This leads to memory corruption. > The fix is simple - you need to add explicit operator=(const > basic_hold_any&). > My compiler is gcc 4.4.7 and I use option -std=c++0x Version of boost is > 1.53 but I don't see that something changed in 1.54 so it should have the > same issue. Please provide a patch which I will gladly apply. Regards Hartmut --------------- http://boost-spirit.com http://stellar.cct.lsu.edu

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