January 2007 - Boost-users - lists.preview.boost.org

Re: [Boost-users] [date_time] timezone rules for different years
by Stephen Turner 19 Jan '07

19 Jan '07

On 2007-01-10 at 15:12:18 GMT, Jeff Garland wrote: > > Personally, I don't have a > use for this or time to implement it myself, but if you are motivated I'm > willing to help you through the process and add into the library when it is > complete. > Jeff, I'm sorry, but I don't think I'm going to have time to work on this. I was keen, but my boss has decided that our users don't care that much about being an hour out six months ago. He's probably right too... -- Stephen Turner, Cambridge, UK http://homepage.ntlworld.com/adelie/stephen/ "The internet is a reflection of our society. If we do not like what we see, the problem is not to fix the mirror, we have to fix society." (Vint Cerf)

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[Graph] Multithreading slowdown on dual core Pentium D
by Brian Townley 19 Jan '07

19 Jan '07

I am experiencing a problem with multithreading using the boost graph library on a dual core Pentium D platform. If I attempt to calculate average path length of a graph, I get at least a 2x slowdown using multiple threads when using johnson_all_pairs_shortest_path. Calculating betweenness is even worse (~7x) when I use brandes_betweenness_centrality and relative_betweenness_centrality. In my test setup, I have no locks anywhere and no shared memory (the graphs are loaded from a file for each iteration in the test). The graph has been defined similar to the following (I can't get actual code on the list due to restrictions from employer): struct VertexProperties { string name; string group; vector<string> properties; }; struct EdgeProperties { string name; double weight; }; typedef boost::property<...> GraphProperty //a group of enums mapped to doubles and ints typedef boost::adjacency_list<listS, vecS, undirectedS, VertexProperties, EdgeProperties, GraphProperty> BoostGraph; All I have to do in my code to see the slowdown is to use a populated graph with johnson_all_pairs_shortest_path in some iterative loop in both one and multiple threads. A real kicker is that currently I can get around this problem by spawning multiple processes to deal with the data load (so I have an interim solution at least) and that gives me a performance improvement by 2x which I expect with dual core... However, I really want to know why this isn't working in a multi-threaded environment. What could I be doing wrong? Is there some proprocessor #define that makes the boost graph library more thread independent? Is there something wrong with the way that I am declaring the graph? Any help is appreciated! Thanks, Thranil

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[filesystem] code pages support
by Игорь Микушкин 19 Jan '07

19 Jan '07

Hi ! namespace fs = boost :: filesystem; boost :: intmax_t filesize = fs :: file_size (argv [1]); This causes an exception if the name consists of cyrillic symbols. (Windows XP, MinGW). Does boost :: filesystem support these names. --------------------------------- Вы уже с Yahoo!? Испытайте обновленную и улучшенную Yahoo! Почту!

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cancel a pending cregex_iterator matching
by Winson Yung 19 Jan '07

19 Jan '07

Hello, I am using the following pesudo code to do a regex match on big buffer (25K of text), sometimes it takes a little longer to come back with a result. I know this partly because the way my regular expression pattern is structured, but I am just wondering whether boost::regex has a mechanism to cancel the pending matching like this one. regex expr(const char* key, regex_constants::perl | regex_constants::icase); cregex_iterator m1(pBuf, pBuf + scope, expr), m2; if (m1 != m2) { // A match found } else { // No match found }

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Serialization and shared_ptr<const X>
by Anders Wang Kristensen 19 Jan '07

19 Jan '07

Hi, I sometimes use shared_ptr<const X> to share read-only resources between different classes. However serializing shared_ptr<const X> causes problems as shown in the attached code. Saving is no problem, but loading fails to compile with an error about converting from const to non-const. I managed to make it compile and run by splitting serialize into load/save. Save is as before, but in load I deserialize into a shared_ptr<X> (no const) and just assign that to the const version. Is this the preferred way? It seems like a hack since I'm saving as one type and loading as another, albeit closely related, type. Thanks. -- Anders #include <boost/serialization/shared_ptr.hpp> #include <boost/serialization/split_member.hpp> #include <boost/archive/xml_iarchive.hpp> #include <boost/archive/xml_oarchive.hpp> #include <fstream> class B { public: int x; friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_NVP(x); } }; class A { public: boost::shared_ptr<const B> bar; friend class boost::serialization::access; //This doesn't work.. template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_NVP(bar); } /* //This works.. template<class Archive> void load(Archive & ar, const unsigned int version) { boost::shared_ptr<B> tmp; ar & BOOST_SERIALIZATION_NVP(tmp); bar = tmp; } template<class Archive> void save(Archive & ar, const unsigned int version) const { ar & BOOST_SERIALIZATION_NVP(bar); } BOOST_SERIALIZATION_SPLIT_MEMBER() */ }; int main(int argc, const char* argv[]) { { boost::shared_ptr<B> b(new B); b->x = 17; A a = { b }; std::ofstream ofs("test.xml"); boost::archive::xml_oarchive oa(ofs); oa << BOOST_SERIALIZATION_NVP(a); } { A a; std::ifstream ifs("test.xml"); boost::archive::xml_iarchive ia(ifs); ia >> BOOST_SERIALIZATION_NVP(a); } }

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Re: [Boost-users] [bjam] Building boost libraries for Win32withalldebugging info
by Nat Goodspeed 18 Jan '07

18 Jan '07

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org [mailto:boost-users- > bounces(a)lists.boost.org] On Behalf Of Lawrence Spector > Sent: Thursday, January 18, 2007 11:54 AM > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] [bjam] Building boost libraries for > Win32withalldebugging info > > We do use the serialization library. What are the caveats to having > 'wchar_t as built-in' off? [Nat] I remembered seeing something about it not working with MSVC 7.1. For some reason I can't find it in the Web archives, but my own Inbox has that message from last November. Turns out it was from YOU, but I didn't realize that when I saw your message earlier today. This is what I was remembering: -----Original Message----- From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Lawrence Spector Sent: Thursday, November 30, 2006 3:50 PM To: Lawrence Spector; boost-users(a)lists.boost.org Subject: Re: [Boost-users] [Serialization] Linker Errors Using Unicode (Was: error C2027: use of undefined type 'boost::serialization::extended_type_info_null<T>'?) Ok, I was playing with the compiler settings and figured it out. Apparently, in order to use this, you *must* have wchar_t treated as a built-in type setting on in VC7.1. Ah ha. Maybe there's a good spot to document that. Thanks for the assistance, Lawrence

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Re: [Boost-users] Deriving Serialization classes
by Pfligersdorffer, Christian 18 Jan '07

18 Jan '07

Hi Miguel, you can find what you seek in the documentation under Reference, Serializable Concept, Pointers, Pointers to Objects of Derived Classes. Two possibilities: * eiter call ar.register_class<A>() * or use the macro BOOST_CLASS_EXPORT(A) Have fun, Christian Pfligersdorffer Software Engineering EOS GmbH > -----Ursprüngliche Nachricht----- > Von: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org]Im Auftrag von Miguel > Silvestre > Gesendet: Montag, 15. Januar 2007 16:30 > An: boost-users(a)lists.boost.org > Betreff: Re: [Boost-users] Deriving Serialization classes > > > Anyone??? > > In the boost code I found this comment: > > // note:if this exception is thrown, be sure that derived pointer > // is either regsitered or exported. > > How can I register a class???????? > > On 1/15/07, Miguel Silvestre <msilvestre(a)gmail.com> wrote: > > Just make the test without a pointer ant it works just fine. > > > > I've looked at the documentation and it only refers to this > problem on > > derivated classes! But I'm not deriving any class. I'm just > including > > the ponter of a class :( > > > > On 1/15/07, Miguel Silvestre <msilvestre(a)gmail.com> wrote: > > > Ok!!! > > > > > > Now I'm getting unregistered_class exceptions when trying > to seryalize > > > a class that has another class. Like: > > > > > > class C : public Serializer > > > { > > > typedef Serializer Parent; > > > public: > > > std::string text; > > > A* m_owner; > > > int32 dasse; > > > C():m_owner(0) > > > { > > > text = "Ola sua puta rabeta!"; > > > dasse = 69; > > > } > > > > > > void Serialize(IArchive& ar, const unsigned int version) > > > { > > > ar.Serialize(dasse); > > > ar.Serialize(text); > > > //ar.Serialize(m_owner); > > > } > > > }; > > > > > > class A : public Serializer > > > { > > > typedef Serializer Parent; > > > public: > > > > > > void Serialize(IArchive& ar, const unsigned int version) > > > { > > > ar.Serialize(dumbi); > > > ar.Serialize(vectorTest); > > > ar.Serialize(matrix); > > > ar.Serialize(testing); > > > ar.Serialize((void*)test_void, sizeof(Vector3f)); > > > } > > > > > > int dumbi; > > > float dumbf; > > > Vector2f vectorTest; > > > Matrix33 matrix; > > > C* testing; > > > Vector3f* test_void; > > > > > > A():dumbi(12), dumbf(69.69f) > > > { > > > testing = new C(); > > > testing->m_owner = this; > > > matrix.SetIdentity(); > > > test_void = new Vector3f(1,2,3); > > > } > > > > > > A(int dumb1, float dumb2) : dumbi(dumb1), dumbf(dumb2) > > > { > > > testing = new C(); > > > testing->m_owner = this; > > > matrix.SetIdentity(); > > > test_void = new Vector3f(1,2,3); > > > } > > > }; > > > > > > If I comment the line that serializes C object from A > > > (ar.Serialize(testing);) everything works fine. > > > I can serialize Object A. And I can serialiaze the Object > C to. But > > > when I have apoibter to C on object A It throws the > unregistered_class > > > exception? > > > > > > Why? > > > > > > How can I avoid this??? > > > On 1/12/07, Robert Ramey <ramey(a)rrsd.com> wrote: > > > > Use binary_object. > > > > > > > > Robert Ramey > > > > > > > > > > > > > > > > _______________________________________________ > > > > Boost-users mailing list > > > > Boost-users(a)lists.boost.org > > > > http://lists.boost.org/mailman/listinfo.cgi/boost-users > > > > > > > > > > > > > -- > > > Miguel Silvestre > > > > > > > > > -- > > Miguel Silvestre > > > > > -- > Miguel Silvestre > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users >

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[Boost.Serialization] Memory management for references
by sadrok 18 Jan '07

18 Jan '07

Hi, I'm loading a class that requires a reference passed to the constructor. The implementation requires loading data into a pointer as explained in the docs. How is the memory for the loaded object handled? Does it automatically get freed when the object goes out of scope? Thanks -- sadrok(a)gmail.com Yahoo! IM: sadrok_za Jabber ID: sadrok(a)jabber.obsidian.co.za

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Re: [Boost-users] [bjam] Building boost libraries for Win32 with alldebugging info
by Nat Goodspeed 18 Jan '07

18 Jan '07

________________________________________ From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Lawrence Spector Sent: Thursday, January 18, 2007 11:44 AM To: boost-users(a)lists.boost.org Subject: [Boost-users] [bjam] Building boost libraries for Win32 with alldebugging info I had built the boost libraries a while ago, using bjam. It looks like all the boost debug libraries were built with Debug Information Format of "C7 Compatible (/Z7)" instead of "Program Database for Edit and Continue (/ZI)" and I'd like to rebuild the libraries with this option turned on. In addition, we're going to need "Treat wchar_t as a built-in type" turned off. It defaults to on. [Nat] We don't use bjam, so I'll let others address your real question. But do you intend to use the Serialization library? If so, beware of turning off 'wchar_t as built-in'.

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[bjam] Building boost libraries for Win32 with all debugging info
by Lawrence Spector 18 Jan '07

18 Jan '07

I had built the boost libraries a while ago, using bjam. It looks like all the boost debug libraries were built with Debug Information Format of "C7 Compatible (/Z7)" instead of "Program Database for Edit and Continue (/ZI)" and I'd like to rebuild the libraries with this option turned on. In addition, we're going to need "Treat wchar_t as a built-in type" turned off. It defaults to on. Any help that can be given in setting the bjam to build correctly for our situation would be much appreciated. Thanks in advance, Lawrence

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