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GSoc 2k14
by Aman Jain 07 Jan '14

07 Jan '14

Hey, I wanna to do Gsoc this year by contributing to some C++ libraries and I am beginner. Actually, I want to contribute by modifying libraries I have once made some part of String library by myself using OOPS I have talked at IRC channel and according to my interest someone suggested me to contribute to https://github.com/boostorg/algorithm Can some one help me out how should I continue ? How to use git-hub here for contribution and bug fixing ? Regards, Aman

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[ANN] Registration for C++Now 2014 is Open
by Boris Kolpackov 07 Jan '14

07 Jan '14

Hi, Registration is now open for the eighth annual C++Now conference (formerly BoostCon) which will be held in Aspen, Colorado, USA, May 12th to 17th, 2014. C++Now is a general C++ conference for C++ experts and enthusiasts. It is not specific to any library/framework or compiler vendor and has three tracks with presentations ranging from hands-on, practical tutorials to advanced C++ design and development techniques. In particular, one of the tracks is dedicated exclusively to tutorials. Last year the conference sold out pretty quickly and we expect it to happen again this year. As a result, we encourage anyone interested in attending to register early. Additionally, early bird hotel reservations end January 10th. For more information on registering, visit: http://cppnow.org/2014/01/2014-registration-is-open/ For early bird hotel reservations, visit: http://cppnow.org/location/lodging/ For general information about the conference, visit: http://cppnow.org/about/ Boris

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[Boost Graph Library] read_graphviz example
by Robert Johannes Langenberg 07 Jan '14

07 Jan '14

Hello, I've recently started using the boost graph library to read a graph in dot format generated with pygraphviz and run some analysis on it. I get the basic example http://www.boost.org/doc/libs/1_55_0/libs/graph/doc/read_graphviz.html#exam… to compile, but it then segfaults when reading the file because it can't find the property "colors" (stack trace below). Now I understand that I didn't define this property but I also have no idea how to do it. Debugging it, i find the name="colors", key=0 and value="red" for the function call below: #11 0x000000010001b40c in boost::put<unsigned long, std::string> (name=@0x100205880, dp=@0x7fff5fbff5f8, key=@0x100204d78, value=@0x100205888) at dynamic_property_map.hpp:292 292 boost::shared_ptr<dynamic_property_map> new_map = dp.generate(name, key, value); For a general understanding of what's happening: What is "key" good for? In the example, where is the variable vertex_color declared? What is this "mass" property and why does it contain vertex_color? What is the type vertex_color_t? The documentation didn't help me, maybe there are easier starting points or i've just looked in the wrong parts of http://www.boost.org/doc/libs/1_55_0/libs/graph/doc/table_of_contents.html If someone could point me to a proper example/tutorial/documentation it'd be greatly appreciated. Best regards, Robert Langenberg Stacktrace: Program received signal SIGABRT, Aborted. 0x00007fff971e8d46 in __kill () (gdb) where #0 0x00007fff971e8d46 in __kill () #1 0x00007fff8fa28f83 in abort () #2 0x00007fff8f35c9eb in abort_message () #3 0x00007fff8f35a39a in default_terminate () #4 0x00007fff8df32887 in _objc_terminate () #5 0x00007fff8f35a3c9 in safe_handler_caller () #6 0x00007fff8f35a424 in std::terminate () #7 0x00007fff8f35b58b in __cxa_throw () #8 0x0000000100016eae in boost::throw_exception<boost::exception_detail::error_info_injector<boost::property_not_found> > (e=@0x7fff5fbfedb8) at throw_exception.hpp:70 #9 0x0000000100016ff0 in boost::exception_detail::throw_exception_<boost::property_not_found> (x=@0x7fff5fbfee90, current_function=0x100061188 "boost::shared_ptr<boost::dynamic_property_map> boost::dynamic_properties::generate(const std::string&, const Key&, const Value&) [with Key = long unsigned int, Value = std::basic_string<char, std::cha"..., file=0x100061008 "/Users/rlangenb/workspace/boost_1_55_0/boost/property_map/dynamic_property_map.hpp", line=268) at throw_exception.hpp:87 #10 0x000000010001ae6e in boost::dynamic_properties::generate<unsigned long, std::string> (this=0x7fff5fbff5f8, name=@0x100205880, key=@0x100204d78, value=@0x100205888) at dynamic_property_map.hpp:268 #11 0x000000010001b40c in boost::put<unsigned long, std::string> (name=@0x100205880, dp=@0x7fff5fbff5f8, key=@0x100204d78, value=@0x100205888) at dynamic_property_map.hpp:292 #12 0x000000010000bf4a in boost::detail::graph::mutate_graph_impl<boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_name_t, std::string, boost::property<boost::vertex_color_t, float, boost::no_property> >, boost::property<boost::edge_weight_t, double, boost::no_property>, boost::property<boost::graph_name_t, std::string, boost::no_property>, boost::listS> >::set_node_property (this=0x7fff5fbff340, key=@0x100205880, node=@0x1002063d0, value=@0x100205888) at graphviz.hpp:775 #13 0x000000010001f006 in boost::read_graphviz_detail::translate_results_to_graph (r=@0x7fff5fbff140, mg=0x7fff5fbff340) at read_graphviz_new.cpp:770

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Re: [Boost-users] [graph][BGL][PBGL] Use of dynamic_properties in parallel
by bminano 07 Jan '14

07 Jan '14

I have found the problem. It seems a cast problem in the dynamic_properties class. I have proposed a patch in the Ticket #9549. I am sorry, I am new to proposing patches so maybe that was not the correct way. -- View this message in context: http://boost.2283326.n4.nabble.com/graph-BGL-PBGL-Use-of-dynamic-properties… Sent from the Boost - Users mailing list archive at Nabble.com.

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How to create distributed_property_map
by Николай Кинаш 05 Jan '14

05 Jan '14

Hello. I try to calculate brandes_betweenness_centrality. #include <boost/graph/use_mpi.hpp> #include <boost/mpi/environment.hpp> #include <boost/mpi/communicator.hpp> #include <boost/graph/distributed/mpi_process_group.hpp> #include <boost/graph/parallel/process_group.hpp> #include <boost/graph/adjacency_list.hpp> #include <boost/graph/distributed/adjacency_list.hpp> #include <boost/graph/small_world_generator.hpp> #include <boost/random/linear_congruential.hpp> #include <boost/graph/distributed/betweenness_centrality.hpp> #include <boost/graph/distributed/graphviz.hpp> #include <boost/graph/rmat_graph_generator.hpp> #include <boost/random/linear_congruential.hpp> #include <iostream> #include <algorithm> #include <math.h> using namespace boost; using namespace graph; using namespace distributed; namespace mpi = boost::mpi; typedef boost::adjacency_list<listS, distributedS<mpi_process_group,vecS>, undirectedS> Graph; typedef boost::unique_rmat_iterator<boost::minstd_rand, Graph> RMATGen; struct no_self_loops { no_self_loops() {} bool operator()(const std::pair<int,int>& e) { return e.first != e.second; } }; int main(int argc, char* argv[]) { boost::mpi::environment env(argc, argv); boost::minstd_rand gen; unsigned int SCALE = atoi(argv[1]); unsigned int EDGE_FACTOR = atoi(argv[2]); unsigned int N = pow(2, SCALE); unsigned int E = EDGE_FACTOR * N; Graph g( boost::make_filter_iterator<no_self_loops> ( RMATGen(gen, N, E, 0.45, 0.15, 0.15, 0.25), RMATGen()), boost::make_filter_iterator<no_self_loops>(RMATGen(), RMATGen()), N); typedef boost::property_map<Graph, vertex_index_t>::type LocalMap; boost::parallel::distributed_property_map<mpi_process_group, LocalMap, ||||||> centrality_map; //brandes_betweenness_centrality(g, centrality_map); } What should be here "|||||" ? I see http://www.boost.org/doc/libs/1_55_0/libs/graph_parallel/doc/html/distribut… template<typename ProcessGroup, typename LocalPropertyMap, typename Key, typename GhostCellS = gc_mapS> Key: The key_type of the distributed property map, which must model the Global Descriptor concept But don`t understand, is not work - typedef property_traits<LocalMap>::key_type key_type; Can you provide example?

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Is there a 1 line wonder for counting iterator and back_inserter - say a counting iterator where the start and step can be specified?
by Brian Davis 05 Jan '14

05 Jan '14

Is there a 1 line wonder for counting iterator and back_inserter - say a counting iterator where the start and step can be specified? The following code creates an vector of angles from zero to N-1 * angle step; std::vector angles; float angle_step = 0.275; int number_angles = 293; std::copy( boost::counting_iterator<float>(0), boost::counting_iterator<float>(number_angles), std::back_inserter(angles) ); std::copy( boost::make_transform_iterator(angles.begin(), boost::bind1st(std::multiplies<float>(), angle_step )), boost::make_transform_iterator(angles.end(), boost::bind1st(std::multiplies<float>(), angle_step )), angles.begin() ); Is there or could there be a counting iterator or other mechanism to do this in 1 line? Say where the start and step could be specified? Thanks

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Re: [Boost-users] Boost-users Digest, Vol 3673, Issue 1
by Markus Lenger 04 Jan '14

04 Jan '14

Hi Larry! The error must be somewhere else in your code. The following program behaves exactly as expected: #include <boost/regex.hpp> #include <string> #include <iostream> int main() { boost::match_results<std::string::const_iterator> match; boost::match_flag_type flags = boost::match_default; boost::regex re(std::string("^XXX_(\\d{3})_\\d{3}$"), boost::regex::perl | boost::regex::icase); std::string the_text = "XXX_123_456"; bool rc = boost::regex_search(the_text,match,re,flags); if (rc) { std::cout << "Number is " << match[1] << std::endl; return 0; } std::cout << "No match found" << std::endl; return 1; } --------- max@switters:~/tmp$ g++ test_regex.cpp -l boost_regex max@switters:~/tmp$ ./a.out Number is 123 Am 2014-01-03 18:00, schrieb boost-users-request(a)lists.boost.org: > Message: 1 > Date: Thu, 2 Jan 2014 16:40:55 -0500 > From: "Larry" <lknain(a)nc.rr.com> > To: <boost-users(a)lists.boost.org> > Subject: [Boost-users] [Regex] Subexpression matching during search > Message-ID: <D06A753E760144CDA0A00B03E0D0DFEE@XV2W> > Content-Type: text/plain; charset="utf-8" > > I have probably missed something in the doc that answers my query but I just can?t see it. > > This is using Perl syntax. > > I had a regex: > > ^(XXX_\d{3,3})_\d{3,3}$ > > It compiles OK but does not match anything in a regex_search. If I remove the parenthesis > > ^XXX_\d{3,3}_\d{3,3}$ > > I get matches. Any clues as to what I am missing? > > > Extract of regex related code lines: > > reg.regex = new boost::regex(reg.reg,boost::regex::perl | boost::regex::icase); > > boost::match_results<string::const_iterator> match; > boost::match_flag_type flags = boost::match_default; > std::string::const_iterator xstart, xend; > > xrc = boost::regex_search(xstart,xend,match,*((*rgi).regex),flags); > > Larry

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[Regex] Subexpression matching during search
by Larry 03 Jan '14

03 Jan '14

I have probably missed something in the doc that answers my query but I just can’t see it. This is using Perl syntax. I had a regex: ^(XXX_\d{3,3})_\d{3,3}$ It compiles OK but does not match anything in a regex_search. If I remove the parenthesis ^XXX_\d{3,3}_\d{3,3}$ I get matches. Any clues as to what I am missing? Extract of regex related code lines: reg.regex = new boost::regex(reg.reg,boost::regex::perl | boost::regex::icase); boost::match_results<string::const_iterator> match; boost::match_flag_type flags = boost::match_default; std::string::const_iterator xstart, xend; xrc = boost::regex_search(xstart,xend,match,*((*rgi).regex),flags); Larry

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[ASIO] Async TCP/UDP server design help
by Terry Lazoki 02 Jan '14

02 Jan '14

I'm having hard time understanding the boost asio design and how i can use it to tackle my problem. My problem: Designing a tcp/udp server that is time efficient. 1. User sends packet through tcp 2. Server receives packet and processes it to build a large tree (n > 20000) 3. Server then parses the new tree and sends a summary packet through udp to another client Conditions/Limitations: - Has to be time efficient, receiving, processing and sending has to be done as fast as possible. - Processing the packet is heavy and can cause delays if its done in the same thread - Parsing the tree is also a little heavy when sending it through udp, can cause delays too Design 1 (2 threads): Thread 1: ASIO TCP and UDP. TCP receives packets and adds it to a circular buffer. While at the same time, processes the shared tree and sends packet through udp. Thread 2: Server grabs packet from circular buffer and processes it Some problems here: - I dont understand the async part here. What happens when tcp receives a packet, if the current thread is continuously parsing the tree and sending packets through udp. Do i need to separate the udp part to another thread? - I have 3 parts of the program that i need to run concurrently, well its really 2 parts and receiving packets through tcp. Any help is appreciated. Thanks,

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Problems installing old BOOST version
by squid squid 02 Jan '14

02 Jan '14

Greetings Everyone I'm a phd student in chemometrics and drug design. I am fairly new to ubuntu C programing although I'm rather experienced in C programing in windows. I have recently come accross a number of codes written in 2005 which I'm interested in learning how they work. Those codes needs BOOST library to complie, however they won't compile on the newest BOOST version installed on my ubuntu 12.04. I set the gcc compiler on lenient so that it ignores all those error messages. The code did compile and ran afterwards. However, when I used GDB debugger to watch how the program flows I noticed that there are likely errors in the way the program runs probably due to using a different BOOST version rather than it's original. Hence I like to install the BOOST version corresponding to the code I downloaded. To do that, I installed Ubuntu 6.02 and downloaded BOOST 1.33.1 both of which were created in late 2005. I downloaded BOOST from: http://www.boost.org/users/history/ but I didnt found any detailed instruction on how to install it. Only vague description on using BOOST jam, I played around with BOOST jam for quite awhile and got roughly the installation outline as follows: -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-* Unpack the trazball in /usr/share/ goto the directory /usr/share/boost_1_33_1/tools/build/jam_src run the script ./build.sh the script creats an executable called bjam, copy that file into /usr/share/boost_1_33_1/ run bjam with: ./bjam "-sTOOLS=gcc" install -*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-* My problems starts when running the ./build.sh script, resulting in tons of error messages and no bjam file created. The errors look like: -*-*-*-*-*-*-*-*-*-*-*-*-*-* ... ... search.c:187: error too many arguments to function 'timestamp' In file included from subst.c:2: jam.h:398:24: error: sys/types.h: No such file or directory jam.h:399:23: error: sys/stat.h: No such file or directory ... ...lots more errors.... -*-*-*-*-*-*-*-*-*-*-*-*-* I would greatly appreciate any info on how to deal with this issue. Sincerely

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