June 2006 - Boost-users - lists.boost.org

Time-dependent graphs
by Thomas Hanne 27 Jun '06

27 Jun '06

Hi, I am currently using an adjacency_list for calculating shortest paths using BGL. Now I would like to make the edge weights time-dependent by calling some own function during the algorithm. Unfortunately, I did not really get things working as described in the book "The Boost Graph Library" with respect to self-defined property maps. (Or should I use a visitor for that purpose?) Maybe you could helb me with some code example on using own code for the edge weights to be used during the Dijkstra algorithm? Many thanks and best regards, Thomas Hanne My current code for calculating shortst paths is like ... typedef adjacency_list<listS, vecS, directedS, no_property, property<edge_weight_t, double> > tGraph; ... int anzKnoten = num_vertices(m_Wegezeiten); vector<vertex_descriptor> vorg(anzKnoten); vector<double> wege(anzKnoten); property_map<tGraph, edge_weight_t>::type gewichte = newget(edge_weight, m_Wegezeiten); property_map<tGraph, vertex_index_t>::type indizes = get(vertex_index, m_Wegezeiten); vertex_descriptor start = vertex(nrVon, m_Wegezeiten); dijkstra_shortest_paths(m_Wegezeiten, start, &vorg.at(0), &wege.at(0), gewichte, indizes, less<double>(), closed_plus<double>(), numeric_limits<int>::max(), 0, default_dijkstra_visitor() );

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[BGL] Automatic cleanning in the graph.
by Seweryn Habdank-Wojewódzki 27 Jun '06

27 Jun '06

Hi everyone Is there a possibility to build a graph which nodes are automatically deleted when in the users code there is no reference to them? Maybe something that combines smart pointers and a graphs? Regards. -- |\/\/| Seweryn Habdank-Wojewódzki `\/\/

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[PATCH] [Parameter] typo in index.rst
by Roman Neuhauser 27 Jun '06

27 Jun '06

Index: libs/parameter/doc/index.rst =================================================================== RCS file: /cvsroot/boost/boost/libs/parameter/doc/index.rst,v retrieving revision 1.30 diff -u -r1.30 index.rst --- libs/parameter/doc/index.rst 10 Apr 2006 20:41:06 -0000 1.30 +++ libs/parameter/doc/index.rst 27 Jun 2006 09:29:46 -0000 @@ -273,7 +273,7 @@ We're going to define our interface in namespace ``graphs``. Since users need access to the keyword objects, but not the tag types, we'll define the keyword objects so they're acceessible through -``graphs``, and we'll hide the tag types away in a tested +``graphs``, and we'll hide the tag types away in a nested namespace, ``graphs::tag``. The library provides a convenient macro for that purpose (MSVC6.x users see this note__):: -- How many Vietnam vets does it take to screw in a light bulb? You don't know, man. You don't KNOW. Cause you weren't THERE. http://bash.org/?255991

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Re: [Boost-users] Boost Variant OutputStreamable
by Ovanes Markarian 27 Jun '06

27 Jun '06

The operator << must be defined in the boost namespace. See the error message of VC:see reference to function template instantiation 'std::basic_ostream<_Elem,_Traits> &boost::operator <<<char,std::char_traits<char>,std::vector<_Ty>,int,std::string,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_>(std::basic_ostream<_Elem,_Traits> &,const boost::variant<T0_,T1,T2> &)' being compiled VC looks for boost::operator<< function and not ::operator<< function. But this should be documented in OutputStreamable. This would compile: #include<iostream> #include<vector> #include<string> #include<boost/variant.hpp> namespace boost { template <typename T> std::ostream& operator<<(std::ostream& os, const std::vector<T>& v) { for(typename std::vector<T>::size_type i = 0; i < v.size(); ++i) os << v[i] << std::endl; return os; } } struct TpTemplateVariant { typedef boost::variant<std::vector<unsigned long>,int, std::string> BoostVariant; }; typedef TpTemplateVariant::BoostVariant Tpvariant; int main () { Tpvariant p(5); std::cout << p; return 0; } Good Luck, Ovanes Markarian On Mon, June 26, 2006 12:45, CLAIRE, Narinder, Group Risk Mgmt wrote: > I apologise for emailing you directly .. but i canno access the mailing list > from work.. > However in response to your response. > > > The following doesn't compile either .. I get the error > > error C2679: binary '<<' : no operator found which takes a right-hand > operand of type 'const T0' (or there is no acceptable conversion) > > On VC8 > > #include<iostream> > #include<vector> > #include<string> > > #include<boost/variant.hpp> > > > > std::basic_ostream<char> &operator<<(std::basic_ostream<char> > &theostream,const std::vector<unsigned long> &theVector) { > for(unsigned long i(0);i<theVector.size();i++) > theostream << theVector[i] << "\n" ; > return theostream; > } > > > struct TpTemplateVariant { > typedef boost::variant< std::vector<unsigned > long>, > > int, > > std::string > >> BoostVariant; > }; > > typedef TpTemplateVariant::BoostVariant Tpvariant; > > int main () { > > Tpvariant p(5); > std::cout << p; > > return 0; > > > > > *********************************************************************************** > The Royal Bank of Scotland plc. Registered in Scotland No 90312. Registered Office: 36 St Andrew > Square, Edinburgh EH2 2YB. > Authorized and regulated by the Financial Services Authority > > This e-mail message is confidential and for use by the > addressee only. If the message is received by anyone other > than the addressee, please return the message to the sender > by replying to it and then delete the message from your > computer. Internet e-mails are not necessarily secure. The > Royal Bank of Scotland plc does not accept responsibility for > changes made to this message after it was sent. > > Whilst all reasonable care has been taken to avoid the > transmission of viruses, it is the responsibility of the recipient to > ensure that the onward transmission, opening or use of this > message and any attachments will not adversely affect its > systems or data. No responsibility is accepted by The Royal > Bank of Scotland plc in this regard and the recipient should carry > out such virus and other checks as it considers appropriate. > Visit our websites at: > http://www.rbos.com > http://www.rbsmarkets.com > *********************************************************************************** > Download this as a file

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[signals] unresolved overloaded function type with gcc 4.1
by Lars Monecke 26 Jun '06

26 Jun '06

Hi, i'm stucked and google does not lead me to the right pages :-( The follwing code example does not compile on gcc 4.1.1 an boost 1.33.1 . It works on msvc.net 7.1. ---code starts here #include <boost/bind.hpp> #include <boost/signal.hpp> #include <iostream> struct Printer { void operator()(int iValue) { std::cout << iValue << "\n"; } }; int main(int /* argc */, char* /* argv[] */) { typedef boost::signal<void (int)> tSignal; tSignal stSignal; Printer stPrinter; stSignal.connect(stPrinter); typedef std::vector<int> tConInts; tConInts cInts; cInts.push_back(1); cInts.push_back(2); cInts.push_back(3); for_each(cInts.begin(), cInts.end(), boost::bind(&tSignal::operator(), boost::ref(stSignal), _1)); return 0; } ---code ends here ---gcc output starts here main.cpp: In function 'int main(int, char*)': main.cpp:37: error: call of overloaded 'bind(<unresolved overloaded function type>, const boost::reference_wrapper<boost::signal<void ()(int), boost::last_value<void>, int, std::less<int>, boost::function<void ()(int), std::allocator<void> > > >, boost::arg<1>&)' is ambiguous /usr/local/gcc-4.1.1/boost-1.33.1/boost/bind/bind_mf_cc.hpp:43: note: candidates are: boost::_bi::bind_t<R, boost::_mfi::mf1<R, T, A1>, typename boost::_bi::list_av_2<A1, A2>::type> boost::bind(R (T::*)(B1), A1, A2) [with R = boost::last_value<void>::unusable, T = boost::signal1<void, int, boost::last_value<void>, int, std::less<int>, boost::function<void ()(int), std::allocator<void> > >, B1 = int, A1 = boost::reference_wrapper<boost::signal<void ()(int), boost::last_value<void>, int, std::less<int>, boost::function<void ()(int), std::allocator<void> > > >, A2 = boost::arg<1>] /usr/local/gcc-4.1.1/boost-1.33.1/boost/bind/bind_mf_cc.hpp:54: note: boost::_bi::bind_t<R, boost::_mfi::cmf1<R, T, A1>, typename boost::_bi::list_av_2<A1, A2>::type> boost::bind(R (T::*)(B1)const, A1, A2) [with R = boost::last_value<void>::unusable, T = boost::signal1<void, int, boost::last_value<void>, int, std::less<int>, boost::function<void ()(int), std::allocator<void> > >, B1 = int, A1 = boost::reference_wrapper<boost::signal<void ()(int), boost::last_value<void>, int, std::less<int>, boost::function<void ()(int), std::allocator<void> > > >, A2 = boost::arg<1>] make: *** [main.o] Error 1 ---gcc output ends here I think something with static_cast is the solultion, but i don't know how? Any hints? Thanks in advance, Lars

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[optional] Why is operator-> disabled
by Jiri Palecek 26 Jun '06

26 Jun '06

Hello, I have been using boost::optional with a reference parameter recently, and I was puzzled by the fact that it is not possible to use operator-> to get the content. I could understand that get_pointer is disabled, but there is always a pointer such as *p==optional.get() and you can't actually get the pointer from operator-> Regards Jiri Palecek

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Re: [Boost-users] Nindi ... Boost Variant
by Ovanes Markarian 26 Jun '06

26 Jun '06

The operator << must be defined in the boost namespace. See the error message of VC:see reference to function template instantiation 'std::basic_ostream<_Elem,_Traits> &boost::operator <<<char,std::char_traits<char>,std::vector<_Ty>,int,std::string,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_,boost::detail::variant::void_>(std::basic_ostream<_Elem,_Traits> &,const boost::variant<T0_,T1,T2> &)' being compiled VC looks for boost::operator<< function and not ::operator<< function. But this should be documented in OutputStreamable. This would compile: #include<iostream> #include<vector> #include<string> #include<boost/variant.hpp> namespace boost { template <typename T> std::ostream& operator<<(std::ostream& os, const std::vector<T>& v) { for(typename std::vector<T>::size_type i = 0; i < v.size(); ++i) os << v[i] << std::endl; return os; } } struct TpTemplateVariant { typedef boost::variant<std::vector<unsigned long>,int, std::string> BoostVariant; }; typedef TpTemplateVariant::BoostVariant Tpvariant; int main () { Tpvariant p(5); std::cout << p; return 0; } Good Luck, Ovanes Markarian On Mon, June 26, 2006 12:45, CLAIRE, Narinder, Group Risk Mgmt wrote: > I apologise for emailing you directly .. but i canno access the mailing list > from work.. > However in response to your response. > > > The following doesn't compile either .. I get the error > > error C2679: binary '<<' : no operator found which takes a right-hand > operand of type 'const T0' (or there is no acceptable conversion) > > On VC8 > > #include<iostream> > #include<vector> > #include<string> > > #include<boost/variant.hpp> > > > > std::basic_ostream<char> &operator<<(std::basic_ostream<char> > &theostream,const std::vector<unsigned long> &theVector) { > for(unsigned long i(0);i<theVector.size();i++) > theostream << theVector[i] << "\n" ; > return theostream; > } > > > struct TpTemplateVariant { > typedef boost::variant< std::vector<unsigned > long>, > > int, > > std::string > >> BoostVariant; > }; > > typedef TpTemplateVariant::BoostVariant Tpvariant; > > int main () { > > Tpvariant p(5); > std::cout << p; > > return 0; > > > > > *********************************************************************************** > The Royal Bank of Scotland plc. Registered in Scotland No 90312. Registered Office: 36 St Andrew > Square, Edinburgh EH2 2YB. > Authorized and regulated by the Financial Services Authority > > This e-mail message is confidential and for use by the > addressee only. If the message is received by anyone other > than the addressee, please return the message to the sender > by replying to it and then delete the message from your > computer. Internet e-mails are not necessarily secure. The > Royal Bank of Scotland plc does not accept responsibility for > changes made to this message after it was sent. > > Whilst all reasonable care has been taken to avoid the > transmission of viruses, it is the responsibility of the recipient to > ensure that the onward transmission, opening or use of this > message and any attachments will not adversely affect its > systems or data. No responsibility is accepted by The Royal > Bank of Scotland plc in this regard and the recipient should carry > out such virus and other checks as it considers appropriate. > Visit our websites at: > http://www.rbos.com > http://www.rbsmarkets.com > *********************************************************************************** >

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Issue with program_options with STLPort using long descriptions
by Tim 26 Jun '06

26 Jun '06

Dear All, I have an issue when using program_options with long description strings when using STLport in debug mode. This occurs within format_paragraph in options_description.cpp and is being found by the _Incrementable check within the STLPort iterator checking. This is using vc71 STLPort 5.0 and Boost 1.33.1 Any help on this issue would be gratefully received. Apologies for asking a question that has been asked previously but there was no resolution posted to the group.

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Strange compiler behaviour with mpl::vector
by Ovanes Markarian 26 Jun '06

26 Jun '06

Hello all! I posted the following message http://lists.boost.org/boost-users/2006/06/20271.php a few days ago, but did not get any replies. I know there is an error in the const_ref class. But nevertheless the problem which occures is that my class accepts a vector of supported types as template parameter. It has two constructors (no default ctor): template<class Seq_> class my_class { public: typedef my_class<Seq_> this_type; explicit inline my_class(const this_type& copy_from) :... {...} template<class TypeFromVector> explicit inline my_class(typename const_ref<TypeFromVector>::type inst) :... {...} }; Now if I try to initialize my_class with type declared in vector I get an error: error C2664: 'discriminated_union<Seq_>::discriminated_union(const discriminated_union<Seq_> &)' : cannot convert parameter 1 from 't1' to 'const discriminated_union<Seq_> &' with [ Seq_=types_vector ] Reason: cannot convert from 't1' to 'const discriminated_union<Seq_>' with [ Seq_=types_vector ] No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called Ok, if I define the ctor param without typename const_ref<...>::type everything goes fine, if I use const_ref it fails. const_ref is defined as follows: template<class Ty> struct const_ref : boost::add_reference < typename boost::add_const < typename boost::remove_reference<Ty>::type >::type > {}; I can understand that the compiler is unable to make a decision which ctor to use, but I do not get an ambiguaty error. It seems like the compiler simply quits expanding templates and uses the last most successful ctor matched before the error. This happens only when I use mpl::vector templated type in conjunction with templated ctor. Other types like below work fine: template<int D_, class Ty_> struct my_pair : mpl::pair<mpl::int_<D_>, Ty_> { typedef my_pair<D_, Ty_> my_type; inline my_pair() {} explicit inline my_pair( typename const_ref<Ty_>::type ty) : second_(ty) {} explicit inline my_pair(const my_type& other) : second_(other.second_) {} inline my_type& operator =(const my_type& other) { second_=other.second_; return *this; } second second_; }; May be some of you have any suggestions. Thanks a lot, Ovanes Markarian

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Serialization of an object with multiple formats
by Vidal Roca 26 Jun '06

26 Jun '06

It is possible to define more than one serialization format for a data structure with the serialization library? If not, has someone some good purposes to make it to? Thanks, Vidal

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