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Problems with msvc 8.0 and build example - please help
by mo mony 10 Jan '08

10 Jan '08

While running cl for msvc 8.0, following the tutorial directions for the example.cpp I get an error " can't find file utility - which is the include file in example. I notice that the path returned in the error has the slashes reversed after the BOOST_ROOT dir. The file definitely exits so I thought it must be a pathing type error. Anyone see this before ? Sorry, I am new to this program/list. I am trying to right some wrappers for C++ to be used by Python. Thanks, Ed ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ

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Non-blocking i/o using ASIO socket
by Chauhan, Vikas 10 Jan '08

10 Jan '08

Hello all, Can you please advise where we need to use "non_blocking_io" flag in ASIO sockets. IIUC, we can do the same using all of the async_xxxx functions provided in the various socket classes. Does it mean that if we do not wish to use ioservice::post() mechanism, we have the option to use "non_blocking_io" flag and implement async functionality? Thanks, Vikas

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Problem compiling some simple code ..
by Eric Fowler 10 Jan '08

10 Jan '08

I have been fiddling with this library off and on for some time ... now am getting this error: /home/eric/boostplay/g0/src/g0.cpp:55: error: no matching function for call to 'add_vertex(Graph (&)())' /home/eric/boostplay/g0/src/g0.cpp:56: error: no matching function for call to 'add_edge(Vertex&, Vertex&, Graph (&)())' on this code: <boost-users(a)lists.boost.org> #ifdef HAVE_CONFIG_H #include <config.h> #endif #include <iostream> #include <cstdlib> #include <boost/config.hpp> #include <boost/graph/adjacency_list.hpp> #include <boost/tuple/tuple.hpp> using namespace std; using namespace boost; typedef adjacency_list<vecS, vecS, undirectedS> Graph; typedef graph_traits<Graph>::vertex_descriptor Vertex; typedef graph_traits<Graph>::edge_descriptor Edge; int main(int argc, char *argv[]) { Graph g(); Vertex v = 0; for(int iv = 0; iv < 10; ++iv) for(int iu = 0; iu < 5; ++iu) { Vertex u; Edge e; bool inserted; u = v; tie(v, inserted) = add_vertex(g); tie(e, inserted) = add_edge(u, v, g); if(inserted) cout << "Inserted edge " << e << " from vertex " << u << " to vertex " << v << endl; else cout << "Failed to insert edge " << e << " from vertex " << u << " to vertex " << v << endl; } return EXIT_SUCCESS; } There was a thread on this a while back which suggested casting the call: tie(e, inserted) = add_edge(u, v, g); to tie(e, inserted) = add_edge(std::size_t(u), std::size_t(v), g); but that did not work. Notice my graph has no properties .. usually I don't make 'em that way, but that should be fine, right? Thanks very much, Eric

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A* implemenation using BGL
by Christopher Gay 09 Jan '08

09 Jan '08

I'm having a problem implementing A*. I used Mr Beevers cities example as a spring board for my own version. I am using bundled properties and I am getting an error that I am unsure of how to correct. The error revolves around the CostMap template parameter for the astar_search. It typedefs the value_type to 'C' and the error tells me that I cannot convert int to 'C' in the std::numeric_limits<C>::max call in astar_dispatch2. I am not passing an object/container for the CostMap parameter. Attached are the files I am working with. Thanks for your help! Chris Gay

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can a edge have more than 2 nodes?
by Meththa 09 Jan '08

09 Jan '08

Hi everyone, I am trying to draw a graph which contains nets with more than 2 nodes. At the moment in the program I am using add_edge() to add the edges to the graph. I give the 2 nodes and also a custom parameter of the net name that this edge belongs to. This solution seems to be a long way of doing things specially when I need to access all the nodes of a particular net. For this I end up running two FOR loops checking each edge to see the net name it belongs to and then accessing the nodes belonging to that edge. Does anyone know of how I can have more than 2 nodes attached to an edge (or net)? Thanks in advance Meth ____________________________________________________________________________________ Never miss a thing. Make Yahoo your home page. http://www.yahoo.com/r/hs

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Bind with Tuple gcc error
by Moyukh 09 Jan '08

09 Jan '08

I was using boost::bind with boost::tuple as shown in the code snippet below. This piece of code compiles and executes fine in Visual Studio 2005 but while compiling with gcc-4.1 It throws error "unresolved overloaded function type" (This code actually does nothing except reproduce the error) I guess its because gcc was unable to figure out which get() to call as there are two version const and non const. Any suggestion how to make it work with gcc as well as VS2005. Code ---------------- #include <boost/tuple/tuple.hpp> #include <boost/bind.hpp> int main(int argc, char * argv[]) { typedef boost::tuple<int, bool, int > myTuple; myTuple mt; boost::bind(&myTuple::get<0>, _1)(mt); return 0; } gcc error.. -------------------- Test.cpp: In function 'int main(int, char**)': Test.cpp:13: error: call of overloaded 'bind(<unresolved overloaded function type>, boost::arg<1> (&)())' is ambiguous ../../../../../Boost/boost/bind/bind_mf_cc.hpp:20: note: candidates are: boost::_bi::bind_t<R, boost::_mfi::mf0<R, T>, typename boost::_bi::list_av_1<A1>::type> boost::bind(R (T::*)(), A1) [with R = int&, T = boost::tuples::cons<int, boost::tuples::cons<bool, boost::tuples::cons<int, boost::tuples::null_type> > >, A1 = boost::arg<1> (*)()] ../../../../../Boost/boost/bind/bind_mf_cc.hpp:30: note: boost::_bi::bind_t<R, boost::_mfi::cmf0<R, T>, typename boost::_bi::list_av_1<A1>::type> boost::bind(R (T::*)()const, A1) [with R = const int&, T = boost::tuples::cons<int, boost::tuples::cons<bool, boost::tuples::cons<int, boost::tuples::null_type> > >, A1 = boost::arg<1> (*)()] Thanks Moyukh

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[iostreams] how to say a filter is closable
by frederic.bron＠alcan.com 09 Jan '08

09 Jan '08

I want to write a filter but this filter needs to do some things when the stream is ending. Is it enough to do the following? I want the close function to be called at the end of the stream. Do I need to category_flag to inherit from (closable_tag)? class my_filter : public io::dual_use_filter { public: template<typename Source> int get(Source&) ; template<typename Sink> bool put(Sink&, int) ; template<typename Device> void close(Device&, std::ios_base::openmode) ; } ; Fred Avis : Ce message et toute pièce jointe sont la propriété d'Alcan et sont destinés seulement aux personnes ou à l'entité à qui le message est adressé. Si vous avez reçu ce message par erreur, veuillez le détruire et en aviser l'expéditeur par courriel. Si vous n'êtes pas le destinataire du message, vous n'êtes pas autorisé à utiliser, à copier ou à divulguer le contenu du message ou ses pièces jointes en tout ou en partie. Notice: This message and any attachments are the property of Alcan and are intended solely for the named recipients or entity to whom this message is addressed. If you have received this message in error please inform the sender via e-mail and destroy the message. If you are not the intended recipient you are not allowed to use, copy or disclose the contents or attachments in whole or in part.

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Switch library review extended to Sunday, Jan 13th
by Stjepan Rajko 09 Jan '08

09 Jan '08

The review for the Switch library has been extended to Sunday, January 13th. I hope that the extended period will provide an opportunity for more reviewers to submit their vote, and give enough time for the discussion on design to resolve. As this library is both small and seen as very useful, it seems preferable to take advantage of the momentum of the ongoing discussion between very knowledgeable reviewers and a very knowledgeable author, and get this ironed out now. Stjepan

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(no subject)
by Lars Schouw 09 Jan '08

09 Jan '08

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Re: [Boost-users] [multi_index] range selection over composit_key problem
by Joaquín Mª López Muñoz 09 Jan '08

09 Jan '08

Hi Oliver, "Kowalke Oliver (QD IT PA AS)" ha escrito: > Hello, > I want to do an range selection over an composit key but I get compiler errors like: [...] > std::pair< > idx_type::iterator, > idx_type::iterator > > p( > idx.range( > boost::make_tuple( mi::unbounded, true), > boost::make_tuple( > boost::lambda::_1 >= 0., > true) ) ); I think there's a misunderstanding here about the usage of composite keys with range(): note that the composite key-based index sorts the elements of p according to a lexicographical order on (descending function, descending active); for instance, the values you insert in your example get sorted as follows: (1.1,false),(1,true),(0,true),(-1,true),(-1,false),(-1.1,true). Now, a fundamental limitation (or chararacteristic, if you wish) of range() is that it can only retrieve *contiguous* ranges, no matter whether the key used is simple, composite, custom or whatever . Your (syntactically incorrect) invocation to idx.range() suggests that you're trying to get the values with function>=0 and active==true, but the set of matching values is not contiguous (it is so by chance with the particular set of values you're using in oyur example, but it wouldn't be if for instance you inserted an additional (1,false) ). In order to do that you'd need to retrieve some larger range and filter out the "undesirable" elements, for example like this: // get all elements with function>=0 and arbitrary active: these do always form // a range. std::pair< idx_type::iterator, idx_type::iterator > p( idx.begin(), idx.upper_bound( boost::make_tuple(0.0) ) ); // filter out the elements with !active for ( ; p.first != p.second; ++p.first) if(p.first->active) std::cout << p.first->function << " " << std::boolalpha << p.first->active << std::endl; Hope this helps, please come back if something's still not clear. Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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