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

Bidirectionnal filtered multigraph
by Robert weldon 03 Aug '04

03 Aug '04

I've created a bidirectional filtered multigraph from an adjacency_list with vectorS and listS as containers for the vertices and egdes respectively. It seems the function edge(u,v,g) does not work properly for this kind of graph. I can detect the existence of an edge (u,v) if I iterate explicitly through the out_edges of the filtered graph but not if I use edge() directly on the filtered graph. Also, I get an exception when I remove an edge that was invisible to the edge(u,v,g) function while the bidirectionnal version of remove_edge for adjacency_list is erasing the edge ID form the in_edge list of the graph. Any idea why edge() does not work in this case? Patrick --------------------------------- Do you Yahoo!? New and Improved Yahoo! Mail - Send 10MB messages!

1 0

Print all routes in a graph
by Daniele Carlucci 03 Aug '04

03 Aug '04

Hi all, I have seen the mail with dijikstra algorithm, there is a way to print all the routes in a graph from a node A and a node B? Thanks Daniele Carlucci

2 4

Function Adaptor that takes an Address
by Ewan Mellor 03 Aug '04

03 Aug '04

I have a function T & foo() and I wish to use a function adaptor to turn this into T * foo2() In other words, I want a function adaptor that takes the address of its given function's result. Does such a thing exist in boost? TIA, Ewan Mellor.

1 0

[BGL] Importing adjacency list from a txt file
by Rui Carvalho 03 Aug '04

03 Aug '04

Hi, I've got a file with the adjacency list of a graph, where each line contains the node index followed by the index of nodes that are adjacent to it (comma-separated). One of the lines of this file could read like: 1,3,4 This would mean that node '1' is adjacent to nodes '3' and '4' (undirected & unweighted graph). I'm declaring it as: typedef adjacency_list < vecS, vecS, undirectedS, no_property, no_property > Graph; Graph g; My question is: is there a simple way of reading the adjacency list into the graph from my txt file? I found Kevin_Bacon, but was looking for something more powerful. Then I found adjacency_list_io.cpp (is it documented?), but it wouldn't compile on MSVC. Am I missing something obvious? Thanks, Rui

2 3

bind and weak pointers
by Jeff Williams 02 Aug '04

02 Aug '04

What is the prefered method of creating a boost::function<void()>, via boost bind, that is calling a member function of a class, and that class instance is held inside the bind object as a weak ptr. Thus, when the function is called, it will try to lock the shared_ptr, if successful it calls the bound function, otherwise it does nothing. Is there an standard way of doing this? Or do I have to write my own custom intermediate function? (which is how I do it now). Jeff

1 0

execution order of slots (signals)
by oliver.kowalke＠t-online.de 02 Aug '04

02 Aug '04

Hello, if I create a signal sig with n slots (slots are ordered by group). What happens if : - I call sig(); and the first called slot removes the slot which is its successor - I call sig(); and the first slot connects a new slot to signal which has a higher priority (group -> higher values are executed at first) with best regards, Oliver -- "Der Spezialist ist ein Barbar, dessen Unwissenheit nicht allumfassend ist." Master's Voice, S.LEM

2 3

RE: [Boost-users] Window API
by Ben Hutchings 02 Aug '04

02 Aug '04

Dr Jekyll <drjekyll(a)empirics.net> wrote: > Hi, > I use a library, which itself use Boost. This library define > > #define Handle boost::shared_ptr Ugh. > But because I intende to use WINAPI , this definition results > in a conflict > > c:\Program Files\Microsoft Visual Studio .NET > 2003\Vc7\PlatformSDK\Include\WinUser.h(3282): error C2751: > 'boost::shared_ptr' : the name of a function parameter cannot > be qualified <snip> > What should I do, if I have to keep the #define line in my library... Don't use that library. Its code quality is so low that you will probably waste more time working around its bugs then you can save by using it. If you disagree with this assessment, perhaps you could write and use a wrapper header that does something like: #ifndef LIBRARY_WRAPPER_H #define LIBRARY_WRAPPER_H #include "library.h" #undef Handle // undefine any other unwanted macros #endif // !defined(LIBRARY_WRAPPER_H)

1 0

lambda and shared_ptr
by Vladimir Krasovsky 02 Aug '04

02 Aug '04

Hello boost-users(a)lists.boost.org, It seems to me that currently lambda's bind does not support shared_ptr as a second argument to bind, when first argument is a pointer-to-member. But boost::bind handles it perfectly. It would be nice for me to be able to write something like this: using namespace boost::lambda; struct SomeClass { int member1; }; boost::shared_ptr<SomeClass> ptr(new SomeClass); (bind(&SomeClass::member1, ptr) = _1)(5); Is it possible with current implementation of lambda? Or I have missed something important? -- Best regards, Vladimir mailto:vkrasovsky@yandex.ru

1 0

[Help on implementation of boost regex]
by hackervalley 02 Aug '04

02 Aug '04

Hello, I try to use boost regex . I don't have a lot of experience of using boost regex . Boost regex examples aren't so explicit for me. So I need some help to parse this example file. Point(1) = {0,0,0,0.1}; Point(2) = {1,0,0,0.1}; Point(3) = {0,1,0,0.1}; Point(4) = {1,1,0,0.1}; Line(1) = {1,2}; Line(2) = {2,4}; Line(3) = {4,3}; Line(4) = {3,1}; Line Loop(5) = {2,3,4,1}; Plane Surface(6) = {5}; I can't read each informations to use it after. I can't match for use IdentificationNumber of Point(IdentificationNumber). Actually my code look so : /* g++ -Wall -O2 -o ifstream ifstream.cc */ #include <iostream> #include <fstream> #include <string> /* boost regex header */ #include <boost/regex.hpp> using namespace std; using namespace boost; int main (int argc, char argv[]) { char buffer[256]; string filename; string inputstring; cout << "Input filename "; cin >> filename; ifstream readfile (filename.c_str (), ios::in); if (!readfile.is_open ()) { cout << "Error opening file" << endl; return 0; } regex exPoint ("Point"); regex exLine ("Line"); regex IdentificationNumber ("[:digit:]"); while (!readfile.eof ()) { readfile.getline (buffer, 200); inputstring = buffer; if (regex_search (inputstring, exPoint)) { cout << "Point" << endl; smatch result; if (regex_search (inputstring, result, IdentificationNumber)) { cout << "Identification Number " << result << endl; } else cout << "Error regex_match" << endl; } if (regex_search (inputstring, exLine)) { cout << "Line" << endl; } cout << buffer << endl; } readfile.close (); return (0); } Thank you for help. Best regards hackervalley http://hackervalley.free.fr

2 1

Accessing Internal Properties
by Jeffrey Holle 02 Aug '04

02 Aug '04

I'm using BGL checked out of CVS on Tue Jun 29 05:25:17 EDT 2004. Also using gcc 3.4.1 on a linux machine. I've a question of how to access internal properties. It appears that there are basically two templated function families for this: get - returns a value get_property_iter_range - returns iterator range get_property - returns a reference Are there more? I'm interested in the later. I've seen in the examples get_property being used to access properties global to a graph, but not edge or vertex properties. What I'd like to see is a varient of get_property (or equivalent) that takes an edge descriptor, so it provides access to a particular edge's named property. Does what I'm looking for exist?

1 0

using boost::shared_ptr with boost::signal
by oliver.kowalke＠t-online.de 01 Aug '04

01 Aug '04

Hi, I want to use boost::shared_ptr with boost::signal. class A { private: int _i; public: A() : _i( 0) {} void operator()( int, std::string & s) { i+= 1; } void operator()( std::string & s, int) { i+= 2; } }; boost::shared_ptr< A > a( new A() ); boost::signal< void( int, std::string &) > rsig; boost::singal< void( std::string &, int) > lsig; rsig.connect( a); lsig.connect( a); rsig(0,"called from right side"); lsig("called from left side",0); Because a is a smart_ptr this code would not compile because operator() is not a member function. If I dereference the smart pointer when I connect to signal, changes of a are never know by the other signal instance. Maybe I can use a proxy class which aggregates the smart pointer but maybe there is a better solution?! with best regards, Oliver -- "Der Spezialist ist ein Barbar, dessen Unwissenheit nicht allumfassend ist." Master's Voice, S.LEM

3 5

boost.graph external properties question.
by Jeffrey Holle 01 Aug '04

01 Aug '04

HI, I'm starting a project that uses boost.graph and I'm trying to decide if I should use internal or external properties. My code that implements external properties is like, for example: typedef boost::graph_traits <GraphT>::vertex_descriptor Vertex; typedef std::map<Vertex,Vertex_Datum,ltDescriptor<Vertex> > VertexData; My question is: Given my use of Vertex as a key of a std::map, it needs to be unique. Is this uniqueness quality maintained across different graphs? That is, can I instanciate 2 GraphT objects and populate both, but maintain only one VertexData container? Assume that I am not defining any internal properties in GraphT.

2 1

Vertex properties in BGL
by Ralph Wessel 01 Aug '04

01 Aug '04

I would like to use the BGL for a project I'm working on, but I haven't been able to find a particular piece of information. The system I'm modeling can be easily represented by a directed graph, but it seems that an essential vertex property can only be calculated on the fly based on the current in-edge and out-edge as the graph is traversed. Can this be supported in the BGL in a way which can feed this vertex property to the supplied algorithms?

2 1

[HELP]How can I print a name of a node in a graph?
by Daniele Carlucci 01 Aug '04

01 Aug '04

Hi everybody, I wanna to print a graph but instead the id I want to print the name of the same. How can I make? I have token the list of the nodes from a list i. In i.name I have the name of the node. The code that I used to initialize the graph is: template <class Graph> void print(Graph& g) { typename Graph::vertex_iterator i, end; typename Graph::out_edge_iterator ei, edge_end; for(boost::tie(i,end) = vertices(g); i != end; ++i) { if (*i!=0){ cout<< *i << " --> "; for (boost::tie(ei,edge_end) = out_edges(*i, g); ei != edge_end; ++ei) cout << target(*ei, g) << " "; cout << endl;} } } void Main() { int nodo, cont, a; nodo=1; typedef graph_traits < file_dep_graph >::vertices_size_type size_type; size_type n_vertices; //Setta n_vertices con il numero di nodi n_vertices=id; // legge il numero di nodi file_dep_graph g(n_vertices); for (i=list.begin(); i != list.end(); ++i) { size_type k; for (cont=0; cont<(*i).v.size(); cont++) { a=(*i).v[cont]; //Connection between node "cont" and all the other nodes add_edge((*i).PID, a, g); } } print(g); Thanks Daniele

3 2

Re: Way to print a route between two nodes
by Gustavo Sÿffffe1nchez 01 Aug '04

01 Aug '04

I don't know exactly how you are traversing those nodes in the path, - ie how do find the path -, but as far as I know you have to use a visitor with an algorithm such as dijisktra shortest paths, so you define the event point, on_finish_vertex for example where you want the visitor to be called. This algorithm also stores in a vector the minimum weight pahts encountered from an specific origin vertex so you can go over those paths from the last vertex to this origin. Hope to be of help ------------------------------ Message: 10 Date: Thu, 29 Jul 2004 15:33:34 +0200 From: Daniele Carlucci Subject: [Boost-users] Way to print a route between two nodes To: boost-users(a)lists.boost.org Message-ID: <4108FCAE.8040301(a)email.it> Content-Type: text/plain; charset=us-ascii; format=flowed Hi all, there is a way to print a route between two nodes? If I have for ie: 8 nodes. A possible route is 1->3->2->6->8 How can I print it? I have only seen that it's used the way to print for every node, all the nodes near that one. Thanks Daniele ------------------------------ ---------------------------------

2 1

serialization for indexed_set?
by Jedediah Smith 01 Aug '04

01 Aug '04

I'm trying to write generic boost::serialization functions for boost:indexed_set and I'm in a bit over my head. The serialization docs say to use something like the following for generic types: template<class Archive, class T> inline void save( Archive & ar, const std::auto_ptr<T> &t, const unsigned int file_version ){ ar << t.get(); } This is a non-intrusive save function for std::auto_ptr. The tricky thing is that the template parameters for indexed_set are much more complicated and the default index may either be regular (set-like) or sequenced (list-like). How would this be handled?

2 1

boost for visual c++
by Jean-Michel besnard 01 Aug '04

01 Aug '04

Hi, How can I install the lib boost::random to use it within Visual C++ (6) ? Is there a built library to be downloaded somewhere or do I have to build it myself ? JM

2 1

std::map(pair) and boost::bind
by Vytautas Leonavicius 30 Jul '04

30 Jul '04

I am often facing the same thing again and again. Say I have a map: map< int, Foo* > m; and I would like to invoke method of Foo on all instances std::for_each(m.begin(), m.end(), boost::bind(&Foo::method, _1 ); The problem is that map contains pair of key and value, not Foo*. Usually I create some function taking pair and invoking method needed on .second. But maybe there is another way to do that? Thanks! Vytautas

2 1

RE: [Boost-users] Re: Bjam- racking my brain
by Brian Braatz 29 Jul '04

29 Jul '04

> Brian Braatz wrote: > > >> Rene Rivera Wrote: > >>build/v2 is not used for building Boost. It's the experimental, and > > > > I am sorry - I am confused and am trying to find my way out: > > > > *- What is listed for download on sourceforge does not reference a > > version of build v1 or bjam v1 or what have you. ( I am confused as to > > how to get the older version) > > OK, some explanation... In SF there are 2 downloads: boost-build-2.0-* > and boost-jam-3.1.*. That boost-build-2.0 is the version 2 I mentioned > which is the experimental version. boost-jam-3.1.* is the scripting > engine BJam (based on Perforce Jam & FreeType Jam) that both V1 and V2 > run on top of. > (snip) Just wanted to thank you Rene for helping me get my head straight on this. I am compiling now with Boost.Build. I have run into another issue that I will be posting on the bjam list (thank you for pointing me to that), but life is definitely nicer. Boost is awesome all by itself, but without the support of the community for those of us getting our heads around these things, boost would not be able to grab more users.

2 1

boost lambda
by Mattias Brändström 29 Jul '04

29 Jul '04

Hello! I am new to the boost lambda library so this might be a naive question. Here goes. This is what I want to do: class Foo { public: int bar() { return 42; } }; int main() { std::vector<Foo> v; v.push_back(Foo()); count_if(v.begin(), v.end(), boost::bind(&Foo::bar, _1) == 42); return 0; } However, I get a comilation error when trying to compile this with g++ version 3.3.2: test.cpp: In function `int main()': test.cpp:17: error: no match for 'operator==' in '`empty_class_expr' not test.cpp:17: sorry, unimplemented: supported by dump_expr test.cpp:17: sorry, unimplemented: boost::bind(R (T::*)(), A1) [with R = int, T = Foo, A1 = boost::arg<1>]((<unnamed>::_1, <expression error>)) == 42' To me it seems that this is something that I should be able to do with the BLL. If someone could point me in the right direction here I would be really greatful! Thanks in advance! Regards, Mattias

3 2

Error Linking Boost Example
by Yuen, Samuel 29 Jul '04

29 Jul '04

Hello folks, I am trying to use boost here and I keep getting the following error when trying to compile dates_as_strings.cpp example: Prelinker invoked. Parsing line from ld: Prelink undefined symbol: get_month_map_ptr__Q25boost9gregorian10greg_monthXv Prelink undefined symbol: _ZTVSt9exception Prelink undefined symbol: _ZTVSt11logic_error Prelink undefined symbol: _ZNSt6localeD1Ev Prelink undefined symbol: _ZNSspLEc Prelink undefined symbol: _Znwm Prelink undefined symbol: _ZNSt11logic_errorD2Ev Prelink undefined symbol: __register_frame_info_table Prelink undefined symbol: __deregister_frame_info Prelink undefined symbol: _ZSt9use_facetISt5ctypeIcEERKT_RKSt6locale Prelink undefined symbol: _ZNKSs2atEm Prelink undefined symbol: _ZNKSs6lengthEv Prelink undefined symbol: _ZNSt6localeC1EPKc Prelink undefined symbol: _ZNSsC1Ev Prelink undefined symbol: _ZNSt12out_of_rangeC2ERKSs Prelink undefined symbol: _ZNSt8ios_base4InitD1Ev Prelink undefined symbol: _ZNSt8ios_base4InitC1Ev Prelink undefined symbol: _ZNSt24__default_alloc_templateILb1ELi0EE10deallocateEPvm Prelink undefined symbol: _ZNSt24__default_alloc_templateILb1ELi0EE8allocateEm Prelink undefined symbol: _ZNKSs7compareERKSs Prelink undefined symbol: _ZNKSt9type_infoeqERKS_ Prelink undefined symbol: __cxa_end_catch Prelink undefined symbol: __cxa_rethrow Prelink undefined symbol: __cxa_begin_catch Prelink undefined symbol: _ZNSsC1ERKSs Prelink undefined symbol: _ZNSsD1Ev Prelink undefined symbol: _ZNSsaSERKSs Prelink undefined symbol: _ZNSsaSEPKc Prelink undefined symbol: _ZNSaIcED1Ev Prelink undefined symbol: _ZNSsC1EPKcRKSaIcE Prelink undefined symbol: _ZNSaIcEC1Ev Prelink undefined symbol: _ZNSt9exceptionD2Ev Prelink undefined symbol: __cxa_throw Prelink undefined symbol: __cxa_allocate_exception Prelink undefined symbol: _Unwind_Resume Prelink undefined symbol: _ZdlPv Prelink undefined symbol: __gxx_personality_v0 Prelink undefined symbol: __cxa_pure_virtual Prelink undefined symbol: _ZTISt11logic_error Prelink undefined symbol: _ZNKSt11logic_error4whatEv Prelink undefined symbol: _ZTVN10__cxxabiv117__class_type_infoE Prelink undefined symbol: _ZTVN10__cxxabiv120__si_class_type_infoE Prelink undefined symbol: as_long_string__CQ25boost9gregorian12greg_weekdayXv Prelink undefined symbol: as_long_string__CQ25boost9gregorian10greg_monthXv Prelink undefined symbol: as_short_string__CQ25boost9gregorian10greg_monthXv ld: Unresolved: boost::gregorian::greg_month::get_month_map_ptr(void) boost::gregorian::greg_weekday::as_long_string(void) const boost::gregorian::greg_month::as_long_string(void) const boost::gregorian::greg_month::as_short_string(void) const The compiler command is: cxx -I/desenv/syuen/tmp/boost_1_31_0 -L/desenv/syuen/tmp/boost_1_31_0/stage/lib -lboost_date_time-gcc-mt-d-1_31 -pthread -o dates_as_strings -D__USE_STD_IOSTREAM -ptv -ptr ./cxx_repository dates_as_strings.cpp The compiler version is: >cxx -V Compaq C++ V6.5-014 for Compaq Tru64 UNIX V5.1A (Rev. 1885) Compiler Driver V6.5-014 (cxx) cxx Driver I have compiled the library using gcc compiler set: export GXX="g++ -pthread" bjam "-sTOOLS=gcc" stage I would appreciate any help. Regards, > Samuel Yuen > System Analyst - PDC > Atos Origin > Rua Itapaiuna 2434 São Paulo / SP > Brazil > Phone +55 (11) 2183-2035 > Mobile +55 (11) 8112-6361 > Fax + 55 (11) 2183-2113 > samuel.yuen(a)atosorigin.com > www.atosorigin.com > > This e-mail and the documents attached are confidential and intended > solely for the addressee; it may also be privileged. If you receive this > e-mail in error, please notify the sender immediately and destroy it. > > As its integrity cannot be secured on the Internet, the Atos Origin > groupliability cannot be triggered for the message content. Although the > sender endeavours to maintain a computer virus-free network, the sender > does not warrant that this transmission is virus-free and will not be > liable for any damages resulting from any virus transmitted. >

1 0

Re: [Boost-users] Running boost::thread compiled on w2k on XP
by Paul Grenyer 29 Jul '04

29 Jul '04

Hi > Is it impossible to compile the boost libraries on > windows 2000 and then expect the created dll:s to work on windows XP? No. It is not impossible. We have done exactly that without any problem at all. We didn't have to do anything special either. We used VC7.1 on Windows 2000, just as you are. I know that's not much practiacl help, but at least you now know it can be done. Regards Paul Paul Grenyer Email: paul(a)paulgrenyer.co.uk Web: http://www.paulgrenyer.co.uk Have you met Aeryn: http://www.paulgrenyer.co.uk/aeryn/? Version 0.3.0 beta now available for download.

3 4

Running boost::thread compiled on w2k on XP
by Ragnar Ouchterlony 29 Jul '04

29 Jul '04

I have tried compiled boost::thread for windows using visual c++ from the visual studio .net 2003 suite. It compiles fine and I can compile things with the created libraries. However, when I move my program and the boost::thread dll:s from windows 2000 to another machine running windows XP, the program just prints out a blank line and exits without any other message. Attached is a program I have used to test out that it is this that is wrong. What have I done wrong? Is it impossible to compile the boost libraries on windows 2000 and then expect the created dll:s to work on windows XP? If this is the case, where can I get hold of the boost::thread libraries for vc71 compiled specifically for windows XP? If not, what could be wrong? /Ragnar Ouchterlony

3 3

uBLAS syntax issues
by Nicholas Andrews 29 Jul '04

29 Jul '04

Here's the formula I want to reproduce in uBLAS: K=P*Mt*(M*P*Mt+R)^-1 Where K, P, M, and R are matrices, and Mt is the transpose of M. I have written the following function: void multi_state_kf::compute_gain(const matrix<double>& dev) { matrix<double> temp=prod(M,newP); matrix<double> transM=trans(M); matrix<double> A=(prod(temp,transM)+dev); permutation_matrix<size_t> pm(A.size2()); lu_factorize(A, pm); matrix<double> el = prod(newP,transM); lu_substitute(A, pm, el); K=el; } This function was completely hacked together as I'm new to uBLAS (and rusty with linear algebra), but it got rid of most of my compile errors. Now only a few remain but I'm not sure what I'm doing wrong. I'm hoping that it will be obvious to someone here. Thanks for your help, Nick

2 1

Assign and MultiArray conflict with precompiled headers
by Bruno Martínez Aguerre 28 Jul '04

28 Jul '04

Hi. I'm trying out the recently accepted Assign library, and also the MultiArray library, which is new to me. I'm in VC7.1, and using the post review version of Assign. Depending on the order I include the libraries in my precompiled header, the linker complains about double definition of MultiArray's extents object. Here are the files that reproduce the problem. //stdafx.h #pragma once #include "boost/multi_array.hpp" #include "boost/assign.hpp" //main.cpp #include "stdafx.h" int main() { boost::multi_array<int, 2> t(boost::extents[3][4]); } I couldn't find relation between the two libraries. Thanks in advance, Bruno Martínez

1 0