February 2014 - Boost-users - lists.preview.boost.org

[interprocess] Determine size of managed_shared_memory
by Kai Benndorf 12 Oct '19

12 Oct '19

Hi all, I want to create a managed_shared_memory in exactly the size I needed. Therefore I do something like this: size = sizeof( common_managed_shared_memory ); size += sizeof( MyClassInSharedMem ); managed_shared_memory segment(create_only, "name", size ); MyClassInSharedMem allocates itself some memory by segment->allocate(). I added this also to the size, but get a boost::interprocess::bad_alloc exception on allocating this additional memory. Are there some magic bytes I forgot to add? Many thanks in advance Kai

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[Range, Phoenix] What am I missing...
by Robert Jones 25 Apr '17

25 Apr '17

Hi Folks Can anyone explain the output of this program... #include <iostream> #include <boost/range/algorithm/copy.hpp> #include <boost/range/counting_range.hpp> #include <boost/range/adaptor/reversed.hpp> #include <boost/range/adaptor/transformed.hpp> #include <boost/phoenix/bind/bind_function.hpp> #include <boost/phoenix/core/argument.hpp> int f( int i ) { return i * 2; } int main( ) { using boost::adaptors::reversed; using boost::adaptors::transformed; using boost::counting_range; using boost::copy; using boost::phoenix::arg_names::_1; copy( counting_range( 1, 5 ) | reversed | transformed( f ), std::ostream_iterator<int>( std::cout, " " ) ); std::cout << std::endl; copy( counting_range( 1, 5 ) | reversed | transformed( bind( f, _1 ) ), std::ostream_iterator<int>( std::cout, " " ) ); std::cout << std::endl; } Which is... 8 6 4 2 1768406272 1768406272 1768406272 1768406272 I'm using Gcc 4.6.2 & Boost 1.53 Thx All.

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[statechart] Passing parameters from event to State Local Storage
by Christophe Bourez 16 Nov '16

16 Nov '16

I need to maintain a parameter into the state local storage. This parameter is initially contained in the event that causes the transition to the target state. I give hereafter a small illustrative example. typename sc = boost::statechart; class EvTest : public sc::event<EvTest> { public: EvTest(std::size_t val) : value(val) {} std::size_t getValue() const { return this->value; } private: std::size_t value; }; class MyStateMachine; class StSource; class StTarget; class StSource : public sc::simple_state<StSource, MyStateMachine> { public: typedef sc::custom_reaction<EvTest> reactions; sc::result react(const EvTest &event) { // How to pass event.getValue() to the target state ? transit<StTarget>(); } }; class StTarget : public sc::simple_state<StTarget, MyStateMachine> { public: StTarget(std::size_t val) : val(value) {} private: std::size_t value; }; Thanks, Christophe

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Statechart serialization
by mbrodeur65 04 Mar '15

04 Mar '15

Hi, I'm looking for a solution to serialize boost::statechart objects. I'm aware that this feature is on the statechart library todo list but was wondering if there are any workaround to achieve this with the latest boost release (1.34) ? thanks for your help ! mbrodeur65 -- View this message in context: http://www.nabble.com/Statechart-serialization-tf4131326.html#a11749139 Sent from the Boost - Users mailing list archive at Nabble.com.

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NT² 3.0 and Boost.SIMD - Stable release
by Joel Falcou 21 Nov '14

21 Nov '14

The first stable release of the 3.x series of MetaScale’s open-source software is available: NT² 3.0. It also includes its spin-off project, Boost.SIMD (not yet a Boost library). Many Issues have been closed since last beta. The main focus of this release cycle was to fix performances issues and to stabilize some parts of the API. Next step will be to separate NT2 and Boost.SIMD into separate repositories, thus making one more step toward Boost.SIMD submission into review. [ http://www.metascale.org/nt%C2%B2-3-0-and-boost-simd ] *Changes & Bug Fixes:* - Major performance improvements in both libraries - Added experimental support for the HPX runtime for parallelization on shared memory systems - Optimizations of many elemental functions, in particuler log/ex, frexp/ldexp and cbrt - More advanced shuffle pattern recognition for SIMD - Fixed issues with Visual Studio 2013 - More functions are force-inlined to ensure good performance - New functions for conversion between types and mixing of vectors of different sizes - Demo applications usable as benchmarks - Better handling of errors when an unsupported function is called - New API for custom memory allocators Full changelog is available at https://github.com/MetaScale/nt2/releases/tag/3.0.0. *How to get it ?* - Source and binary packages can be downloaded here: http://nt2.metascale.org/downloads - The release is also available on Github : https://github.com/MetaScale/nt2/releases - The main master branch is still under development : https://github.com/MetaScale/nt2

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[Thread] Read-write locks
by lfrfly＠icqmail.com 18 Sep '14

18 Sep '14

I'm trying to create a standard read/write lock using Boost Threads, and I'm having a bit of difficulty mapping the Boost concepts onto the usual ones. A read/write lock should have several states: Locked for reading (multiple threads may lock at once), locked for writing (only one thread may lock, and no threads may be locked for reading at the same time), and unlocked. Ideally it would be nice if an RWL which is locked for reading may temporarily upgrade to locked for writing, then return to the locked for reading state. Boost supports several relevant notions of locking: shared locking, upgrade locking, and exclusive locking. This to me is a confusing distinction. In particular, a shared_mutex seems appropriate as the basis for a RWL, but is lock_upgrade() the equivalent of a write lock and lock_shared the equivalent of a read lock? This is unclear. If "upgrade locking" is not the same as "exclusive locking", then is an upgrade lock actually exclusive? Could someone please clarify this.

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[Statechart] How to decide between post_event and process_event atrun time ?
by Philippe DAVID 22 Jul '14

22 Jul '14

Hi, I have a method in which I want to post/process an event. The thing is, this method can be called from outside the state machine (so I need to call process_event), or indirectly by a reaction of the state machine (in this case I must call post_event since process_event is not reentrant). I don't want to write 2 distinct methods to do this (one that calls post, and the other process), I would much rather prefer adding a 'if' in my method that tells me if I have to call process_event or post_event (if I'm being called indirectly by the state machine or not). Is there a way to do this with statechart ? regards, Philippe

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Boost test and openmpi
by Martin Vymazal 21 May '14

21 May '14

Hello, I have the following code: #define BOOST_TEST_DYN_LINK #define BOOST_TEST_MODULE mpi_functionality #include <boost/test/unit_test.hpp> #include "mpi.h" struct MPI_Functionality_Fixture { MPI_Functionality_Fixture() { m_argc = boost::unit_test::framework::master_test_suite().argc; m_argv = boost::unit_test::framework::master_test_suite().argv; } int m_argc; char** m_argv; }; BOOST_FIXTURE_TEST_SUITE( MPI_Functionality_TestSuite, MPI_Functionality_Fixture ) BOOST_AUTO_TEST_CASE( mpi_functionality_parenv_init ) { MPI_Init(&m_argc,&m_argv); } BOOST_AUTO_TEST_CASE( mpi_functionality_parenv_finalize ) { MPI_Finalize(); } BOOST_AUTO_TEST_SUITE_END() The code compiles fine, but I have the following problem when I try to run it. When I run as 'mpirun ./my_executable' or 'mpirun -np 3 ./my_executable' everything goes fine. On the other hand, when I run as ./my_executable I get the following error: unknown location(0): fatal error in "mpi_functionality_parenv_finalize": unrecognized signal Outside of Boost, it is perfectly possible to write a program which calls MPI_Init and MPI_Finalize and it does not have to be used with mpirun. I wonder if this (different) behavior of Boost test is normal. I did not find any remarks regarding Boost test and mpi in the tutorial. Best regards, Martin Vymazal

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conflicting intmax_t definitions - Boost 1.53 and gcc 4.8 incompatibility?
by Nate Finch 09 Apr '14

09 Apr '14

I recently upgraded to Ubuntu Trusty Tehr, and now the C++ project I'm working on won't build. It looks like the stdlib and Boost aren't working nicely together for some reason. A bunch of typedefs are conflicting between the two, below is one of the errors, where intmax_t is getting defined in two places. I'm not sure what changed, but I now have gcc (Ubuntu/Linaro 4.8.2-14ubuntu2) 4.8.2 and boost Version: 1.53.0.0ubuntu2 Here's an example error message: /usr/include/inttypes.h:290:8: error: reference to ‘intmax_t’ is ambiguous extern intmax_t imaxabs (intmax_t __n) __THROW __attribute__ ((__const__)); ^ In file included from /usr/lib/gcc/x86_64-linux-gnu/4.8/include/stdint.h:9:0, from /usr/include/inttypes.h:27, from src/uint256.h:11, from src/key.h:12, from src/crypter.h:8, from src/keystore.h:8, from src/script.h:14, from src/script.cpp:11: /usr/include/stdint.h:134:19: note: candidates are: typedef long int intmax_t typedef long int intmax_t; ^ In file included from /usr/include/boost/math_fwd.hpp:12:0, from /usr/include/boost/math/common_factor_ct.hpp:13, from /usr/include/boost/variant/variant.hpp:44, from /usr/include/boost/variant.hpp:17, from src/script.h:12, from src/script.cpp:11: /usr/include/boost/cstdint.hpp:306:50: note: typedef boost::long_long_type boost::intmax_t typedef ::boost::long_long_type intmax_t; Any help would be much appreciated. I'm fine with downgrading something, I'm just not sure what to downgrade.... or if there's an actual fix, that's cool too. -- View this message in context: http://boost.2283326.n4.nabble.com/conflicting-intmax-t-definitions-Boost-1… Sent from the Boost - Users mailing list archive at Nabble.com.

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Problems calling make_reversed_graph in a call to dijkstra from version 1.48
by Berit Dangaard Brouer 08 Apr '14

08 Apr '14

Hi, First of all thank you for providign the boost BGL library. I use it extensively. I am having some problems with some code, that works just fine using boost version 1.46, but cannot compile using version 1.48 and higher. I have a Bidirectional Graph using bundled properties defined as: struct Port { Port(int index=-1, int type=-1, int port_code=0, string UN="NN", string name="NN", int service_id=-1 ): m_index(index), m_type(type), m_port_code( port_code), UNLOCODE(UN), m_name(name), m_service_id(service_id) {} int m_index; int m_type;//0 port, 1 port call int m_port_code; string UNLOCODE; string m_name; int m_service_id; }; struct Edge { Edge( int id=-1, int type=-1, double weight=0.0, double cost=0.0, double dual_cost=0.0, double util=0.0, double cap=0.0, double r_cap=0.0 ) : m_idx(id), m_type(type), m_weight(weight) , m_cost(cost), m_dual_cost(dual_cost), m_utilization(util), m_capacity(cap), m_res_cap(r_cap) {} unsigned int m_idx; int m_type;//0 is load edge, 1 is voyage edge, 2 forfeited edge (commodity link) double m_weight; //distance double m_cost; //cost - only on load/unload/transhipment edges double m_dual_cost; double m_utilization; double m_capacity; double m_res_cap; //residual capacity }; //Graph typedef adjacency_list< vecS , vecS , bidirectionalS, Port, Edge> mcf_graph; I am trying to make a call to dijkstra on a reversed graph as follows: (the reversed graph is also a filtered graph, but I do not think this is an issue: dijkstra_shortest_paths (make_reverse_graph(fg), before_p, predecessor_map ( &p[0] ).distance_map ( &d[0] ).weight_map ( get ( &Edge::m_weight, fg) ).vertex_index_map ( get ( vertex_index,fg ) ) ); which works fine in 1.46, but it seems in 1.48 I can no longer use make_reverse_graph(<mcf_graph&>) (returning a reverse graph) with the bundled properties from fg. and I get the error (compressed summary - full details attached) usr/include/boost/property_map/property_map.hpp:354:56: error: no match for 'operator[]' in '((const boost::bundle_property_map<boost::adjacency_list<boost::vecS, boost::vecS, boost::bidirectionalS, Port, Edge>, boost::detail::edge_desc_impl<boost::bidirectional_tag, long unsigned int>, Edge, double>&)pa)[k]' /usr/include/boost/property_map/property_map.hpp:354:56: note: candidate is: In file included from /usr/include/boost/graph/adjacency_list.hpp:44:0, from /home/chrkr/git/lsndp/include/ipheuristic.h:36, from /home/chrkr/git/lsndp/src/ipheuristic.cpp:29: /usr/include/boost/graph/properties.hpp:399:15: note: T& boost::bundle_property_map<Graph, Descriptor, Bundle, T>::operator[](boost::bundle_property_map<Graph, Descriptor, Bundle, T>::key_type) const [with Graph = boost::adjacency_list<boost::vecS, boost::vecS, boost::bidirectionalS, Port, Edge>; Descriptor = boost::detail::edge_desc_impl<boost::bidirectional_tag, long unsigned int>; Bundle = Edge; T = double; boost::bundle_property_map<Graph, Descriptor, Bundle, T>::reference = double&; boost::bundle_property_map<Graph, Descriptor, Bundle, T>::key_type = boost::detail::edge_desc_impl<boost::bidirectional_tag, long unsigned int>] /usr/include/boost/graph/properties.hpp:399:15: note: no known conversion for argument 1 from 'const boost::detail::reverse_graph_edge_descriptor<boost::detail::edge_desc_impl<boost::bidirectional_tag, long unsigned int> >' to 'boost::bundle_property_map<boost::adjacency_list<boost::vecS, boost::vecS, boost::bidirectionalS, Port, Edge>, boost::detail::edge_desc_impl<boost::bidirectional_tag, long unsigned int>, Edge, double>::key_type {aka boost::detail::edge_desc_impl<boost::bidirectional_tag, long unsigned int>}' From various sources I understand that as of 1.48 reverse graph is no longer an image of the graph, but another object, where I need the actual property maps and the property maps of the reversed graph, but I did not get much wiser on how to call dijkstra with the reversed graph given these new description. I tried defining the reverse graph as a separate object reverse_graph<mcf_graph> r_fg=reverse_graph(fg); dijkstra_shortest_paths (r_fg), before_p, predecessor_map ( &p[0] ).distance_map ( &d[0] ).weight_map ( get ( &Edge::m_weight, r_fg) ).vertex_index_map ( get ( vertex_index, r_fg ) ) ); indicating that I am not getting the right properties for the reverse graph: equired from here /usr/include/boost/graph/properties.hpp:420:44: error: no type named 'vertex_bundled' in 'class boost::reverse_graph<boost::adjacency_list<boost::vecS, boost::vecS, boost::bidirectionalS, Port, Edge> >' /usr/include/boost/graph/properties.hpp:421:42: error: no type named 'edge_bundled' in 'class boost::reverse_graph<boost::adjacency_list<boost::vecS, boost::vecS, boost::bidirectionalS, Port, Edge> >' /usr/include/boost/graph/properties.hpp:425:7: error: no type named 'vertex_bundled' in 'class boost::reverse_graph<boost::adjacency_list<boost::vecS, boost::vecS, boost::bidirectionalS, Port, Edge> >' /usr/include/boost/graph/properties.hpp:429:7: error: no type named 'vertex_bundled' in 'class boost::reverse_graph<boost::adjacency_list<boost::vecS, boost::vecS, boost::bidirectionalS, Port, Edge> >' /usr/include/boost/graph/properties.hpp:432:70: error: no type named 'vertex_bundled' in 'class boost::reverse_graph<boost::adjacency_list<boost::vecS, boost::vecS, boost::bidirectionalS, Port, Edge> >' /usr/include/boost/graph/properties.hpp:434:7: error: no type named 'vertex_bundled' in 'class boost::reverse_graph<boost::adjacency_list<boost::vecS, boost::vecS, boost::bidirectionalS, Port, Edge> >' /home/chrkr/git/lsndp/src/ipheuristic.cpp:939:132: error: no matching function for call to 'get(double Edge::*, boost::reverse_graph<boost::adjacency_list<boost::vecS, boost::vecS, boost::bidirectionalS, Port, Edge> >&)' /home/chrkr/git/lsndp/src/ipheuristic.cpp:939:132: note: candidates are: In file included from /usr/include/boost/graph/adjacency_list.hpp:36:0, from /home/chrkr/git/lsndp/include/ipheuristic.h:36, from /home/chrkr/git/lsndp/src/ipheuristic.cpp:29: /usr/include/boost/property_map/property_map.hpp:179:19: note: template<class T> const T& get(const T*, std::ptrdiff_t) /usr/include/boost/property_map/property_map.hpp:179:19: note: template argument deduction/substitution failed: /home/chrkr/git/lsndp/src/ipheuristic.cpp:939:132: note: mismatched types 'const T*' and 'double Edge::*' In file included from /usr/include/boost/graph/graphviz.hpp:25:0, from /home/chrkr/git/lsndp/include/data.h:19, from /home/chrkr/git/lsndp/include/ipheuristic.h:46, from /home/chrkr/git/lsndp/src/ipheuristic.cpp:29: /usr/include/boost/property_map/dynamic_property_map.hpp:322:1: note: template<class Key> std::string boost::get(const string&, const boost::dynamic_properties&, const Key&) /usr/include/boost/property_map/dynamic_property_map.hpp:322:1: note: template argument deduction/substitution failed: Is the problem the bundled properties from the original graph or ? -- Best Regards, Ph.D. Berit Dangaard Brouer Post Doc. DTU Management Engineering, Management Science Technical University of Denmark Department of Management Engineering Produktionstorvet, Bygning 426 2800 Kgs. Lyngby blof(a)dtu.dk <mailto:blof@man.dtu.dk> www.ms.man.dtu.dk <http://www.ms.man.dtu.dk> http://www.maersk.com/innovation/leadingthroughinnovation/enerplan/ Please read about the ENERPLAN project here <http://www.maersk.com/innovation/leadingthroughinnovation/enerplan/>

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[asio] resolver::cancel() problem
by Matthew Edwards 14 Mar '14

14 Mar '14

In my application (and a separate test program) it seems as though the cancel() function on the resolver does not work as intended. For async resolves, the cancel functionality should abort them immediately and pass an 'operation aborted' error code to the callback handler. In my tests, I will resolve an invalid domain (this causes the resolve to take a few seconds, to demonstrate the problem), sleep for 100ms, then call cancel on the resolver object. No cancelling actually occurs, and the callback is simply triggered after a few seconds with a "No host found" error code, not the expected operation aborted. Has anyone experienced this before, or know how I might be using the resolver incorrectly?

3 2

Boost qi parser
by Uthpal Urubail 04 Mar '14

04 Mar '14

{ name = "new" sub_name = "SUBTITLE" values = { 1, 2, 3; } input_values = { 1, 2, 3; 5, 5, 6 10, 12, 3} type = input intval = 100 } Can some one help me to write the parser for the above format? I am trying something like below and this doesn’t seem to work for me. template <typename Iterator> struct keys_and_values : qi::grammar<Iterator, mapDef()> { keys_and_values() : keys_and_values::base_type(query) { using namespace qi; query = '{' >> *lit(' ') >> pair >> *(lit(' ') >> *lit(' ') >> pair) >> *lit(' ') >> '}'; pair = key >> -(*lit(' ') >> "=" >> *lit(' ') >> value); key = +char_("a-zA-Z0-9_") ; value = +char_("a-zA-Z0-9") | lexeme[('{' >> +char_("\"@+*.( , ) $ a-zA-Z0-9_ -") >> '}')] | lexeme[('"' >> +char_("\"@+*.( , ) $ a-zA-Z0-9_ -") >> '"')]; } qi::rule<Iterator, mapDef()> query; qi::rule<Iterator, std::pair<std::string, std::string>()> pair; qi::rule<Iterator, std::string()> key, value; }; Any help would be highly appriciated. Regards, UJ

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[BGL] Shared nodes on path
by Sensei 03 Mar '14

03 Mar '14

Dear all, I have a simple question about the most efficient way of finding shared nodes between a path and a graph. Let me be more explicit. I have an oriented graph G, and a very simple graph P, which is actually a simple oriented path (n0 -> n1 -> ... -> nK). I need to find *all* the possible shared paths between P and G with the same length as P. For instance, being P = n1 -> n2 -> n3 -> n4 -> n5 -> n6 we may find that the G and P share only two sub-paths n1 -> n2 -> n3 n5 -> n6 I'd like to find all sub-graphs that connect the two paths, for instance having n1 -> n2 -> n3 -> n10 -> n5 -> n6 n1 -> n2 -> n3 -> n42 -> n5 -> n6 with the constraint that the solution must be a path with the same length as P, therefore a solution as these n1 -> n2 -> n3 -> n9 -> n8 -> n5 -> n6 n1 -> n2 -> n3 -> n5 -> n6 would not be acceptable. I know I can do it manually, but I think a BGL-aware solution is quite better that a manual search :) Thanks & Cheers!

2 4

Error compiling Boost::graph crs_graph
by Andrea Cassioli 28 Feb '14

28 Feb '14

Dear all, I have been using the compressed_sparse_row_graph quite extensively in past. Now, I am working under Linux with Boost 1.55 and I am lost trying to compile the following toy piece of code: #include <vector> #include <boost/graph/compressed_sparse_row_graph.hpp> int main() { typedef boost::compressed_sparse_row_graph<boost::directedS, boost::no_property, int> gtype; std::vector<boost::graph_traits<gtype>::edge_descriptor> edges; std::vector< int > distances; gtype graph(boost::edges_are_unsorted_t(), edges.begin(), edges.end(), distances.begin(), edges.size()); return 0; } Just compile with g++ 4.8.2 and you get In file included from /usr/include/boost/graph/detail/compressed_sparse_row_struct.hpp:33:0, from /usr/include/boost/graph/compressed_sparse_row_graph.hpp:29, from prova_icl.cpp:2: /usr/include/boost/graph/detail/histogram_sort.hpp: In instantiation of ��void boost::graph::detail::split_into_separate_coords(InputIterator, InputIterator, std::vector<Property>&, std::vector<Property>&) [with InputIterator = __gnu_cxx::__normal_iterator<boost::detail::csr_edge_descriptor<long unsigned int, long unsigned int>*, std::vector<boost::detail::csr_edge_descriptor<long unsigned int, long unsigned int> > >; VerticesSize = long unsigned int]��: /usr/include/boost/graph/compressed_sparse_row_graph.hpp:466:46: required from ��boost::compressed_sparse_row_graph<boost::directedS, VertexProperty, EdgeProperty, GraphProperty, Vertex, EdgeIndex>::compressed_sparse_row_graph(boost::edges_are_unsorted_t, InputIterator, InputIterator, EdgePropertyIterator, boost::compressed_sparse_row_graph<boost::directedS, VertexProperty, EdgeProperty, GraphProperty, Vertex, EdgeIndex>::vertices_size_type, const GraphProperty&) [with InputIterator = __gnu_cxx::__normal_iterator<boost::detail::csr_edge_descriptor<long unsigned int, long unsigned int>*, std::vector<boost::detail::csr_edge_descriptor<long unsigned int, long unsigned int> > >; EdgePropertyIterator = __gnu_cxx::__normal_iterator<int*, std::vector<int, std::allocator<int> > >; VertexProperty = boost::no_property; EdgeProperty = int; GraphProperty = boost::no_property; Vertex = long unsigned int; EdgeIndex = long unsigned int; boost::compressed_sparse_row_graph<boost::directedS, VertexProperty, EdgeProperty, GraphProperty, Vertex, EdgeIndex>::vertices_size_type = long unsigned int]�� prova_icl.cpp:14:34: required from here /usr/include/boost/graph/detail/histogram_sort.hpp:226:51: error: conversion from ��boost::detail::csr_edge_descriptor<long unsigned int, long unsigned int>�� to non-scalar type ��std::pair<long unsigned int, long unsigned int>�� requested std::pair<VerticesSize, VerticesSize> edge = *begin; What the xxx is happening? In my understanding sounds like there conversion from an edge_descriptor to a pair....Any ideas?? Best, Andrea Cassioli

1 0

boost::optional with BOOST_FUSION_ADAPT_ADT broken?
by Andrew 28 Feb '14

28 Feb '14

There's an issue using get expressions returning optionals with BOOST_FUSION_ADAPT_ADT, demonstrated in the simplest case below. Optional<T> is trying initialize its internal T object using the attribute proxy object returned by fusion, but this can only degrade to optional<T> and not T, so the assignment fails. C++ wizard, K-Ballo, took a quick look at this in #boost and seemed to suggest it's the way op= is SFINAEd up for optional. Does anyone have a work around for this? #include <boost/optional.hpp> #include <boost/fusion/adapted/struct/adapt_struct.hpp> #include <boost/fusion/adapted/adt/adapt_adt.hpp> #include <boost/fusion/algorithm/auxiliary/copy.hpp> struct A { boost::optional<int> x; }; struct B { boost::optional<int> y; }; BOOST_FUSION_ADAPT_STRUCT(B, (boost::optional<int>, y)) BOOST_FUSION_ADAPT_ADT(A, (boost::optional<int>, boost::optional<int>, obj.x, obj.x = val)) int main() { A a; B b; // doesn't work: boost::fusion::copy (a, b); // this works: // boost::fusion::copy (b, a); }

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boost graph, Using Bundled Properties and Internal Properties at the same time
by Paolo Bolzoni 27 Feb '14

27 Feb '14

Dear list, Related to the other email of me I woud like to use the subgraphs class, but the base graph needs two internal properties: vertex_index and edge_index. However in my program I use bundled properties as suggested in this list some time ago. Now I have this problem, is possible to use internal and bundled properties in the same graph? Or can I use subgraph in another way? Your faithfully, Paolo

1 0

Strange problem with boost/graph/subgraph.hpp
by Paolo Bolzoni 27 Feb '14

27 Feb '14

Dear list, I cannot compile a simple example using the subgraph implementation. I enclosed the code in the bottom of this email. It is quite short, but it is the whole code. It does not compile with errors from inside boost/graph/detail/adjacency_list.hpp about the impossiblity of making a reference to void. I read the subgraph documentation but I cannot understand why it does not work. Can anyone enlighten me? Your faithfully, Paolo The code: ------------------ >8 #include <boost/graph/adjacency_list.hpp> #include <boost/graph/subgraph.hpp> typedef boost::adjacency_list < boost::listS, boost::listS, boost::undirectedS > main_graph; typedef boost::subgraph <main_graph> sub_graph; typedef boost::graph_traits<sub_graph>::vertex_descriptor Bvertex; 8< ------------------

1 1

[ASIO] Streambuf not containing full line
by Gonzalo Garramuno 27 Feb '14

27 Feb '14

I am using asio asynchronically. I have: void tcp_session::start_read() { // Set a deadline for the read operation. // input_deadline_.expires_from_now(boost::posix_time::seconds(30)); // input_deadline_.expires_at(boost::posix_time::pos_infin); // Start an asynchronous operation to read a newline-delimited message. boost::asio::async_read_until(socket(), input_buffer_, '\n', boost::bind(&tcp_session::handle_read, shared_from_this(), boost::asio::placeholders::error)); } void tcp_session::handle_read(const boost::system::error_code& ec) { if (stopped()) return; if (!ec) { // Extract the newline-delimited message from the buffer. std::string msg; std::istream is(&input_buffer_); is.exceptions( std::ifstream::failbit | std::ifstream::badbit | std::ifstream::eofbit ); try { while ( std::getline(is, msg) ) { // parse msg here (gets truncated to last 256 chars or so) std::cerr << msg << std::endl; } } catch ( const std::ios_base::failure& e ) { std::cerr << "getline failure " << e.what() << std::endl; } } My problem is that I am seeing messages that are not a full line, but a truncation of the line, as if a buffer gets full with 256 characters. I am unsure what I am doing wrong. I get a getline failure saying basic_ios::clear.

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[fusion] nth runtime element of a sequence
by MM 26 Feb '14

26 Feb '14

Hello, I just wanted to confirm there's no provided method to get the n'th element of say a fusion vector where n is known at runtime, except of handling it explicitkly with a switch case? Thanks MM

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Project link error with Wave on OSX
by Olivier Prat 26 Feb '14

26 Feb '14

I've just updated a project that was working under XCode 4 with boost 1.48 to XCode 5 and boost 1.55 (installed with MacPorts). Now I have a link error with Wave which wasn't the case before. This somehow baffles me as I thought everything was template based. I am also linking with libboost-wave.mt.a but that doesn't solve the problem. The linker errors are, among 6 others: Undefined symbols for architecture x86_64: "boost::wave::cpplexer::new_lexer_gen<__gnu_cxx::__normal_iterator<char*, std::string>, boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > >, boost::wave::cpplexer::lex_token<boost::wave::util::file_position< boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > > >::new_lexer(__gnu_cxx::__normal_iterator<char*, std::string> const&, __gnu_cxx::__normal_iterator<char*, std::string> const&, boost::wave::util::file_position<boost::wave::util::flex_string<char, std::char_traits<char>, std::allocator<char>, boost::wave::util::CowString<boost::wave::util::AllocatorStringStorage<char, std::allocator<char> >, char*> > > const&, boost::wave::language_support)", referenced from: I've tried forcing std::string as the BOOST_WAVE_STRINGTYPE, but that just changes the signatures of the undefined symbols. I fail to see what has changed and I am completely stuck. I would have understood if I had a compiler error but this is a link error. Is this something to do with the standard C++ library? For my project, C++ dialect is C++98 and the standard library is libstdc++. Thanks in advance, Olivier

2 4

Question on writing HTTP parser
by gomti 25 Feb '14

25 Feb '14

Hello. I'm newbie for boost library. I'm trying to write a HTTP Parser, which handles the HTTP message coming from the proxy server. I don't know much about the boost, so I'm really confused on what to use to write my functionality. When I search on the internet, some say that I need to used Boost.Asio and Some say Boost.Spirit. When I looked over the document for each, I found that Boost.Asio is like network library for C++ and Boost.Spirit is for writing compilers. As I mention above, I want to write a http parser. I think the relevant one is the following: https://github.com/joyent/http-parser Please give me some advice. Since this is my first posting, I don't know the culture in this mailing list so if I'm doing some mistake in here, please let me know. Thanks.

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Parallel Dijkstra with Predecessors
by Florian Meier 25 Feb '14

25 Feb '14

Hi, I am trying to use the parallel Dijkstra implementation with predecessors, but I am not able to compile it. Please have a look at the following diff against boost_1_53_0/libs/graph_parallel/example/dijkstra_shortest_paths.cpp (You can find the modified version attached.) ------------------------------------------- @@ -45,8 +45,10 @@ /* An undirected, weighted graph with distance values stored on the vertices. */ +typedef adjacency_list_traits<vecS, distributedS<mpi_process_group, vecS>, undirectedS>::vertex_descriptor vertex_descriptor; + typedef adjacency_list<vecS, distributedS<mpi_process_group, vecS>, undirectedS, - /*Vertex properties=*/property<vertex_distance_t, float>, + /*Vertex properties=*/property<vertex_distance_t, float, property<vertex_predecessor_t, vertex_descriptor> >, /*Edge properties=*/property<edge_weight_t, float> > Graph; @@ -71,7 +73,7 @@ // Compute shortest paths from vertex 0 dijkstra_shortest_paths(g, start, - distance_map(get(vertex_distance, g))); + distance_map(get(vertex_distance, g)).predecessor_map(get(vertex_predecessor, g))); // Output a Graphviz DOT file std::string outfile = filename; ------------------------------------------- This (actually get(vertex_predecessor, g)) gives me ------------------------------------------- In file included from /usr/include/boost/property_map/parallel/distributed_property_map.hpp:706:0, from /usr/include/boost/property_map/property_map.hpp:645, from /usr/include/boost/graph/properties.hpp:19, from /usr/include/boost/mpi/graph_communicator.hpp:30, from /usr/include/boost/mpi.hpp:27, from /usr/include/boost/graph/distributed/mpi_process_group.hpp:30, from dijkstra_shortest_paths.cpp:16: /usr/include/boost/property_map/parallel/impl/distributed_property_map.ipp: In instantiation of ‘void boost::parallel::distributed_property_map<ProcessGroup, GlobalMap, StorageMap>::handle_message<Reduce>::handle_multiput(int, int, const std::vector<boost::unsafe_pair<typename boost::property_traits<StorageMap>::key_type, typename boost::property_traits<StorageMap>::value_type> >&, boost::graph::parallel::trigger_receive_context) [with Reduce = boost::property_reduce<boost::vertex_predecessor_t>::apply<boost::detail::parallel::global_descriptor<long unsigned int> >; ProcessGroup = boost::graph::distributed::mpi_process_group; GlobalMap = boost::detail::parallel::global_descriptor_property_map<long unsigned int>; StorageMap = boost::vec_adj_list_vertex_property_map<boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_predecessor_t, boost::detail::parallel::global_descriptor<long unsigned int> > >, boost::property<boost::edge_locally_owned_t, bool, boost::property<boost::edge_target_processor_id_t, short int, boost::property<boost::edge_weight_t, float> > >, boost::no_property, boost::listS>, boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_predecessor_t, boost::detail::parallel::global_descriptor<long unsigned int> > >, boost::property<boost::edge_locally_owned_t, bool, boost::property<boost::edge_target_processor_id_t, short int, boost::property<boost::edge_weight_t, float> > >, boost::no_property, boost::listS>*, boost::detail::parallel::global_descriptor<long unsigned int>, boost::detail::parallel::global_descriptor<long unsigned int>&, boost::vertex_predecessor_t>; typename boost::property_traits<StorageMap>::value_type = boost::detail::parallel::global_descriptor<long unsigned int>; typename boost::property_traits<StorageMap>::key_type = long unsigned int]’: /usr/include/boost/property_map/parallel/impl/distributed_property_map.ipp:255:18: required from ‘void boost::parallel::distributed_property_map<ProcessGroup, GlobalMap, StorageMap>::handle_message<Reduce>::setup_triggers(boost::parallel::distributed_property_map<ProcessGroup, GlobalMap, StorageMap>::process_group_type&) [with Reduce = boost::property_reduce<boost::vertex_predecessor_t>::apply<boost::detail::parallel::global_descriptor<long unsigned int> >; ProcessGroup = boost::graph::distributed::mpi_process_group; GlobalMap = boost::detail::parallel::global_descriptor_property_map<long unsigned int>; StorageMap = boost::vec_adj_list_vertex_property_map<boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_predecessor_t, boost::detail::parallel::global_descriptor<long unsigned int> > >, boost::property<boost::edge_locally_owned_t, bool, boost::property<boost::edge_target_processor_id_t, shor t int, boost::property<boost::edge_weight_t, float> > >, boost::no_property, boost::listS>, boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_predecessor_t, boost::detail::parallel::global_descriptor<long unsigned int> > >, boost::property<boost::edge_locally_owned_t, bool, boost::property<boost::edge_target_processor_id_t, short int, boost::property<boost::edge_weight_t, float> > >, boost::no_property, boost::listS>*, boost::detail::parallel::global_descriptor<long unsigned int>, boost::detail::parallel::global_descriptor<long unsigned int>&, boost::vertex_predecessor_t>; boost::parallel::distributed_property_map<ProcessGroup, GlobalMap, StorageMap>::process_group_type = boost::graph::distributed::mpi_process_group]’ /usr/include/boost/property_map/parallel/impl/distributed_property_map.ipp:35:3: required from ‘boost::parallel::distributed_property_map<ProcessGroup, GlobalMap, StorageMap>::distributed_property_map(const ProcessGroup&, const GlobalMap&, const StorageMap&, const Reduce&) [with Reduce = boost::property_reduce<boost::vertex_predecessor_t>::apply<boost::detail::parallel::global_descriptor<long unsigned int> >; ProcessGroup = boost::graph::distributed::mpi_process_group; GlobalMap = boost::detail::parallel::global_descriptor_property_map<long unsigned int>; StorageMap = boost::vec_adj_list_vertex_property_map<boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_predecessor_t, boost::detail::parallel::global_descriptor<long unsigned int> > >, boost::property<boost::edge_locally_owned_t, bool, boost::property<boost::edge_target_processor_id_t, short int, boost::property<boost::edge_weight_t, floa t> > >, boost::no_property, boost::listS>, boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_predecessor_t, boost::detail::parallel::global_descriptor<long unsigned int> > >, boost::property<boost::edge_locally_owned_t, bool, boost::property<boost::edge_target_processor_id_t, short int, boost::property<boost::edge_weight_t, float> > >, boost::no_property, boost::listS>*, boost::detail::parallel::global_descriptor<long unsigned int>, boost::detail::parallel::global_descriptor<long unsigned int>&, boost::vertex_predecessor_t>]’ /usr/include/boost/graph/distributed/adjacency_list.hpp:3468:50: required from ‘typename boost::property_map<boost::adjacency_list<OutEdgeListS, boost::distributedS<ProcessGroup, InVertexListS, InDistribution>, DirectedS, VertexProperty, EdgeProperty, GraphProperty, EdgeListS>, Property>::type boost::get(Property, boost::adjacency_list<OutEdgeListS, boost::distributedS<ProcessGroup, InVertexListS, InDistribution>, DirectedS, VertexProperty, EdgeProperty, GraphProperty, EdgeListS>&) [with Property = boost::vertex_predecessor_t; OutEdgeListS = boost::vecS; ProcessGroup = boost::graph::distributed::mpi_process_group; InVertexListS = boost::vecS; InDistribution = boost::defaultS; DirectedS = boost::undirectedS; VertexProperty = boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_predecessor_t, boost::detail::parallel::global_descriptor<long unsigned int> > >; EdgeProperty = boost::property<boost::edge_weight_t, float>; GraphProperty = boost::no_property; EdgeL istS = boost::listS; typename boost::property_map<boost::adjacency_list<OutEdgeListS, boost::distributedS<ProcessGroup, InVertexListS, InDistribution>, DirectedS, VertexProperty, EdgeProperty, GraphProperty, EdgeListS>, Property>::type = boost::parallel::distributed_property_map<boost::graph::distributed::mpi_process_group, boost::detail::parallel::global_descriptor_property_map<long unsigned int>, boost::vec_adj_list_vertex_property_map<boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_predecessor_t, boost::detail::parallel::global_descriptor<long unsigned int> > >, boost::property<boost::edge_locally_owned_t, bool, boost::property<boost::edge_target_processor_id_t, short int, boost::property<boost::edge_weight_t, float> > >, boost::no_property, boost::listS>, boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_distance_t, float, boost::property<b oost::vertex_predecessor_t, boost::detail::parallel::global_descriptor<long unsigned int> > >, boost::property<boost::edge_locally_owned_t, bool, boost::property<boost::edge_target_processor_id_t, short int, boost::property<boost::edge_weight_t, float> > >, boost::no_property, boost::listS>*, boost::detail::parallel::global_descriptor<long unsigned int>, boost::detail::parallel::global_descriptor<long unsigned int>&, boost::vertex_predecessor_t> >]’ dijkstra_shortest_paths.cpp:77:106: required from here /usr/include/boost/property_map/parallel/impl/distributed_property_map.ipp:236:47: error: no match for call to ‘(boost::property_reduce<boost::vertex_predecessor_t>::apply<boost::detail::parallel::global_descriptor<long unsigned int> >) (const long unsigned int&, boost::parallel::distributed_property_map<boost::graph::distributed::mpi_process_group, boost::detail::parallel::global_descriptor_property_map<long unsigned int>, boost::vec_adj_list_vertex_property_map<boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_predecessor_t, boost::detail::parallel::global_descriptor<long unsigned int> > >, boost::property<boost::edge_locally_owned_t, bool, boost::property<boost::edge_target_processor_id_t, short int, boost::property<boost::edge_weight_t, float> > >, boost::no_property, boost::listS>, boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, boost::property<boost::vertex_distance_t , float, boost::property<boost::vertex_predecessor_t, boost::detail::parallel::global_descriptor<long unsigned int> > >, boost::property<boost::edge_locally_owned_t, bool, boost::property<boost::edge_target_processor_id_t, short int, boost::property<boost::edge_weight_t, float> > >, boost::no_property, boost::listS>*, boost::detail::parallel::global_descriptor<long unsigned int>, boost::detail::parallel::global_descriptor<long unsigned int>&, boost::vertex_predecessor_t> >::value_type&, const boost::detail::parallel::global_descriptor<long unsigned int>&)’ values[i].second)); ^ In file included from /usr/include/boost/graph/distributed/breadth_first_search.hpp:23:0, from /usr/include/boost/graph/breadth_first_search.hpp:404, from /usr/include/boost/graph/dijkstra_shortest_paths.hpp:21, from dijkstra_shortest_paths.cpp:19: /usr/include/boost/graph/parallel/properties.hpp:90:11: note: candidates are: class apply ^ /usr/include/boost/graph/parallel/properties.hpp:95:9: note: T boost::property_reduce<boost::vertex_predecessor_t>::apply<T>::operator()(T) const [with T = boost::detail::parallel::global_descriptor<long unsigned int>] T operator()(T key) const { return key; } ^ /usr/include/boost/graph/parallel/properties.hpp:95:9: note: candidate expects 1 argument, 3 provided /usr/include/boost/graph/parallel/properties.hpp:96:9: note: T boost::property_reduce<boost::vertex_predecessor_t>::apply<T>::operator()(T, T, T) const [with T = boost::detail::parallel::global_descriptor<long unsigned int>] T operator()(T key, T, T y) const { return y; } ^ /usr/include/boost/graph/parallel/properties.hpp:96:9: note: no known conversion for argument 1 from ‘const long unsigned int’ to ‘boost::detail::parallel::global_descriptor<long unsigned int>’ ------------------------------------------- What is wrong here? Greetings, Florian

2 1

boost/graph/metric_tsp_approx.hpp patch, is there interest?
by Paolo Bolzoni 25 Feb '14

25 Feb '14

Dear list, In the boost/graph/metric_tsp_approx.hpp:224 is a note // TODO: This is will be O(n^2) if vertex storage of g != vecS. Since I am exactly in this situation I made a patch for my use, I added a bundled property to MSTImpl's vertices to contain a descriptor to keep track of the original graph vertices. It is a small modification, but since there is a TODO perhaps there is interest? If so how should I share it? Of course any comment is welcome. Your sincerely, Paolo

1 0

[icl] Icl broken for c++11's hint semantics. Fix provided.
by Joachim Faulhaber 25 Feb '14

25 Feb '14

Dear Icl users, due to a subtle effect of the changed hint semantics for associative containers, the icl library is broken in versions <= 1.55.0 when used with new STL-libraries that implement the new c++11 standard. This bug is fixed in the upcoming Boost 1.56.0. (see regression tests at http://www.boost.org/development/tests/master/developer/icl.html) Since the release of boost 1.56.0 seems to take longer than planned due to restructuring efforts for modular-boost, users of Boost.Icl affected by the problem may choose to pull the fixed Boost.Icl directly from the git repository and replace your_boost_1_55_0/boost/icl with the new code. The libs/icl part does not need an update. Another possibility is to apply the patch-file diff_icl_1_55_0_and_master.patch that is attached to this post to your local boost library 1.55.0: 1. cd to your_boost_1_55_0 root directory. your_boost_1_55_0> 2. From the command line type your_boost_1_55_0> patch -p2 < diff_icl_1_55_0_and_master.patch You may check the patched library by moving to your_boost_1_55_0/libs/icl/test and run your_boost_1_55_0/libs/icl/test> bjam Sorry for the inconvenience. Best regards, Joachim P.S.: For those interested in details of the issue here is a report: The semantics of insertion with hint in associative containers changed in c++11 form insert-after-hint (c++98/03) to insert-before-hint (c++11) see e.g. proposal N1780: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1780.html so for an associative container c of type C, a value x and an iterator hint c.insert(hint, x); //tries to insert x right after hint in c++98 c.insert(hint, x); //tries to insert x before hint in c++11 In accordance with this behavior, if using the insert function std::pair<bool, iterator> C::insert(value_type const& x); (success, hint) = c.insert(x); the iterator hint of unsuccessful insertion is the matching hint, pointing to [c++98] the last element y in c that is not greater x, so x can be inserted *after* that hint. [c++11] the first element z in c that is greater than x, so x can be inserted *before* that hint. In Boost.Icl I used the returned hint-iterator of the insert function, that always returned the last overlapping interval y for an inserted interval x given the interval's exclusive-less ordering under c++98. With the changed hint semantics, this returned hint-iterator did not point to the last interval y overlapping x anymore but to the first interval z not overlapping x. Therefore the code was broken and returned false results. -- Interval Container Library [Boost.Icl] http://www.joachim-faulhaber.de

1 0

Intrusive unordered set and thread safety
by Dave Davoren 25 Feb '14

25 Feb '14

Hi, I have been playing around with the boost intrusive unordered set. If my application is multi-threaded I do not see any way to make the set thread safe at a bucket level. I have seen a previous post from November 2012 "[Intrusive] unordered_set and thread safety" which asked the same question. At that point it was not implemented but I have not seen any updates in that area since. My question is, has it been implemented or is there a plan to implement such a feature in the near future? Thank you, Dave.

2 2