June 2008 - Boost-users - lists.boost.org

Boost.Graph set of edges
by James Sutherland 17 Mar '09

17 Mar '09

Can you do something like typedef boost::graph_traits<Graph>::edge_descriptor Edge; Edge e; .... std::set<Edge> edges; edgeSet.insert( e ); I am getting compiler errors that imply that the edge_descriptor does not implement the < operator. Thanks, James

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serial programs
by Steven Woody 02 Mar '09

02 Mar '09

Hi, I want to write a portable program which need to read/write serial ports. How can boost help this? Thank you. ( I got know basic serial programming in Linux but I have no idea how that it done in Windows ) -- woody then sun rose thinly from the sea and the old man could see the other boats, low on the water and well in toward the shore, spread out across the current.

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[date_time] posix_time::time_duration::operator<< fails for hours>23
by Soren Dreijer 04 Feb '09

04 Feb '09

I'm creating a posix_time::time_duration object based on the minutes() helper function. If I specify a large value, such as 2000, I get a time_duration of 33:20:00. Take a look at the following piece of code, though: time_duration td = minutes(2000); cout << to_simple_string(td); // OK cout << td; // Fails with an assertion in VS2008 The latter call fails with the following assertion in strftime.c on line 658: _VALIDATE_RETURN( ( ( timeptr->tm_hour >=0 ) && ( timeptr->tm_hour <= 23 ) ), EINVAL, FALSE) Apparently, operator<< expands to _expandtime(), which doesn't allow values for the hour to be greater than 23. Is this intended behavior, or should I just always use to_simple_string() rather than the convenient operator<< ?

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[graph] property_map from bundled properties in a subgraph, how?
by Christian Rössel 28 Nov '08

28 Nov '08

Hi, thanks for the great graph library! My first attempts with boost.graph were quite successful, but now I'm stuck. My question is: How can I get a property_map from bundled properties in a subgraph? (boost 1.34.1, g++ and VC8) In the beginning I had a bidirectional graph with bundled properties and I used a property map from the edge's bundled properties: #include <boost/graph/adjacency_list.hpp> #include <boost/graph/subgraph.hpp> using namespace boost; struct VertexProperty { // ... }; struct EdgeProperty { double length_; // ... }; typedef adjacency_list<vecS, vecS, bidirectionalS, VertexProperty, EdgeProperty> Graph; int main () { Graph g; typedef property_map<Graph, double EdgeProperty::*>::type EdgeWeightMap; EdgeWeightMap ewm = get (&EdgeProperty::length_, g); // use ewm in an algorithm ... return 0; } Everthing worked fine. Then, I had to change the graph-type from adjacency_list to subgraph ... typedef subgraph< adjacency_list<vecS, vecS, bidirectionalS, property<vertex_index_t, int, VertexProperty>, property<edge_index_t, int, EdgeProperty> > > Subgraph; int main () { Subgraph g; typedef property_map<Subgraph, double EdgeProperty::*>::type EdgeWeightMap; EdgeWeightMap ewm = get (&EdgeProperty::length_, g); // use ewm in an algorithm ... return 0; } ... and got this compile error: In instantiation of `boost::property_map<Subgraph, double EdgeProperty::*>': subgraph_property_map.cpp:45: instantiated from here ../../vendor/boost_1_34_1-multithread/boost/graph/properties.hpp:355: error: no type named `vertex_bundled' in `class Subgraph' ../../vendor/boost_1_34_1-multithread/boost/graph/properties.hpp:356: error: no type named `edge_bundled' in `class Subgraph' ../../vendor/boost_1_34_1-multithread/boost/graph/properties.hpp:360: error: no type named `vertex_bundled' in `class Subgraph' ../../vendor/boost_1_34_1-multithread/boost/graph/properties.hpp:360: error: `value' is not a member of `<declaration error>' ../../vendor/boost_1_34_1-multithread/boost/graph/properties.hpp:364: error: no type named `vertex_bundled' in `class Subgraph' ../../vendor/boost_1_34_1-multithread/boost/graph/properties.hpp:364: error: `value' is not a member of `<declaration error>' ../../vendor/boost_1_34_1-multithread/boost/graph/properties.hpp:367: error: no type named `vertex_bundled' in `class Subgraph' ../../vendor/boost_1_34_1-multithread/boost/graph/properties.hpp:367: error: `value' is not a member of `<declaration error>' ../../vendor/boost_1_34_1-multithread/boost/graph/properties.hpp:369: error: no type named `vertex_bundled' in `class Subgraph' ../../vendor/boost_1_34_1-multithread/boost/graph/properties.hpp:369: error: `value' is not a member of `<declaration error>' Is there a way to use property maps from bundled properties in a subgraph? If not, can you give me a hint for a workaround, please. Thanks and best regards, Christian __

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Random: Using random generators with runtime parameters
by Hans Mull 23 Nov '08

23 Nov '08

Hi! How can I use random generators with multiple parameters such as linear_congruential with parameters that are only known at runtime? Thanks in advance, Hans

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Visual C++ 2003 and Boost 1.35
by Tomek Jerzykowski 13 Oct '08

13 Oct '08

Hello! I'm having a problem with using Boost 1.35 on Visual C++ 2003 SP1. Take a look at the following very simple program: ------------------------------------ #include "stdafx.h" #include <boost/interprocess/sync/interprocess_upgradable_mutex.hpp> int _tmain(int argc, _TCHAR* argv[]) { int i = 0; unsigned int j = 2; j < i; return 0; } ------------------------------------ It does nothing, just emits a compiler warning. Unfortunately, this warning is followed by lots of meaningless messages related to the included Boost header: ------------------------------------ BoostTest2.cpp c:\BoostTest2\BoostTest2.cpp(11) : warning C4018: '<' : signed/unsigned mismatch c:\Program Files\boost\boost_1_35_0\boost\interprocess\sync\interprocess_upgradable_mut ex.hpp(621) : see reference to class template instantiation 'boost::interprocess::upgradable_lock<M>' being compiled with [ M=boost::interprocess::interprocess_mutex ] c:\Program Files\boost\boost_1_35_0\boost\interprocess\sync\interprocess_upgradable_mut ex.hpp(621) : see reference to class template instantiation 'boost::interprocess::upgradable_lock<M>' being compiled with [ M=boost::interprocess::interprocess_mutex ] ------------------------------------ If I remove #include <boost..., the extra messages go away. It looks to me like compiler bug. The exe produced is probably ok, but the amount of spam in output window makes using Boost very cumbersome. Is there any way to make these messages go away?

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boost::program_options
by Duy Nguyen 09 Oct '08

09 Oct '08

When I try to use the boost::program_options library to read a property file, I got the error when I run "make" on Cygwin (I installed Cygwin on WIndows XP). > make g++.exe -I /cygdrive/c/MyTest/Test1/include/boost-1_34_1/ -c TestInit.cpp Test.cpp TestDriver.cpp g++.exe -I /cygdrive/c/MyTest/Test1/include/boost-1_34_1/ -c TestInit.cpp Test.cpp TestDriver.cpp g++.exe -I /cygdrive/c/MyTest/Test1/include/boost-1_34_1/ -c TestInit.cpp Test.cpp TestDriver.cpp g++.exe TestInit.o Test.o TestDriver.o -o "TestDriver" -L/cygdrive/c/MyTest/Test1/lib -lboost_program_options-gcc34-mt-d-1_34_1 -lg2c Info: resolving vtable for boost::program_options::variables_mapby linking to __imp___ZTVN5boost15program_options13variables_mapE (auto-import) Then when I run my program, it does not work. If I comment out the "try ... catch" block which uses the boost::propram_options library then it compiles and works fine. Please show me how to fix it. Thank you.

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boost::filesystem exception not caught on MacOS X
by Lothar May 21 Sep '08

21 Sep '08

Hi, I have a strange problem that an exception thrown by a boost::filesystem directory_iterator is not caugth on MacOS X. Please consider the following code: ("const string &dir" is a parameter) bool retVal = true; try { directory_iterator i(dir); directory_iterator end; while (i != end) { // do something ++i; } } catch (...) { retVal = false; } While this works perfectly on Windows and Linux (the exception is caught fine), on MacOS I get the following: terminate called after throwing an instance of 'boost::filesystem::basic_filesystem_error<boost::filesystem::basic_path<std::string, boost::filesystem::path_traits> >' what(): boost::filesystem::basic_directory_iterator constructor Abort trap The program runs fine (withouth the trap) if I comment out the upper lines. I use the boost 1.34.0 lib built as universal binary on MacOS 10.5, according to the instructions at http://svn.boost.org/trac/boost/wiki/CMakeConfigAndBuild I link to the static non-debug mt version of boost_filesystem. Exceptions within my program are caught fine, just this boost exception is not caught. The program is also compiled as non-debug. Any help would be very much appreciated. Regards, Lothar

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Boost Graph Library and Boehm Garbage Collector
by FBSL 08 Sep '08

08 Sep '08

Hello I am having trouble to garbage-collect adjacency_list<>. I have instanciated it with correctly garbage-collected vectors and lists (I have copied vecS and listS definitions, and added Boehm GC's default allocator so that they are garbage-collected). In my application I need to dynamically allocate many graphs, but it does not work, there is a (big) memory leak. Unfortunately, there is no template argument in adjacency_list<> to specify Boehm GC's allocator. Does anyone have a hint ? Snippet code "main.cpp" follows, compiled with Boost Graph Library 1.32, Boehm GC 6.4 and G++ 3.3.5, with command line : $ g++ -o main main.cpp -lgc -lgccpp -- #include <boost/graph/adjacency_list.hpp> #include <gc/gc_allocator.h> #include <gc/gc_cpp.h> #include <iostream> #include <vector> #include <list> using namespace std; using namespace boost; namespace boost { struct collected_vecS {}; struct collected_listS {}; template <class ValueType> struct container_gen<collected_vecS, ValueType> { typedef vector<ValueType,gc_allocator<ValueType> > type; }; template <class ValueType> struct container_gen<collected_listS, ValueType> { typedef list<ValueType,gc_allocator<ValueType> > type; }; template <> struct parallel_edge_traits<collected_vecS> { typedef allow_parallel_edge_tag type; }; template <> struct parallel_edge_traits<collected_listS> { typedef allow_parallel_edge_tag type; }; namespace detail { template <> struct is_random_access<collected_vecS> { enum { value = true }; typedef true_type type; }; } } typedef adjacency_list<collected_vecS, collected_vecS, directedS, no_property, no_property, no_property, collected_listS> graph; int main() { // leaks... while(true){ graph * g=new (UseGC) graph; for(unsigned int i=0; i<100; ++i){ add_vertex(*g); } for(unsigned int i=0; i<100; ++i){ for(unsigned int j=0; j<100; ++j){ add_edge(i,j,*g); } } } }

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Simply including boost/bind.hpp causes compilation error
by Ken Smith 28 Aug '08

28 Aug '08

Here is my environment. % g++ -v Using built-in specs. Target: i686-apple-darwin9 Configured with: /var/tmp/gcc/gcc-5483~1/src/configure --disable-checking -enable-werror --prefix=/usr --mandir=/share/man --enable-languages=c,objc,c++,obj-c++ --program-transform-name=/^[cg][^.-]*$/s/$/-4.0/ --with-gxx-include-dir=/include/c++/4.0.0 --with-slibdir=/usr/lib --build=i686-apple-darwin9 --with-arch=apple --with-tune=generic --host=i686-apple-darwin9 --target=i686-apple-darwin9 Thread model: posix gcc version 4.0.1 (Apple Inc. build 5483) Boost 1.35.0 (also produced same issue with Boost 1.34.1) Here is the code. 1 #include <boost/lambda/lambda.hpp> 2 #include <boost/lambda/construct.hpp> 3 #if defined(INCLUDE_BOOST_BIND) 4 # include <boost/bind.hpp> 5 #endif 6 #include <iostream> 7 #include <iterator> 8 #include <algorithm> 30 31 int main() 32 { 33 using namespace std; 34 using namespace boost::lambda; 35 36 typedef std::istream_iterator<int> in; 37 std::for_each(in(std::cin), in(), std::cout << (_1 * 3) << " " ); 76 } (The astute reader will note discontinuity in the line numbering. This is a playground for my exploration with boost. All elided lines are #if 0'ed. Here is the compile command line and the compilation error, both edited for clarity. g++ -c -g -Wall -fexceptions -DINCLUDE_BOOST_BIND -I/path/to/boost-1.35.0/include main.cpp -o main.o main.cpp: In function 'int main()': main.cpp:37: error: '_1' was not declared in this scope I have seen these related articles from the archives of this list but none of the suggestions eliminated the error. I added the inclusion of boost/lambda/construct.hpp per one of the suggestions there. Its inclusion or exclusion doesn't change the behavior. http://thread.gmane.org/gmane.comp.lib.boost.user/35128 http://thread.gmane.org/gmane.comp.lib.boost.user/16630 http://thread.gmane.org/gmane.comp.lib.boost.user/16887 As you may imagine, the elided (and commented out) lines contain actual uses of boost/bind.hpp but it is a mystery to me that simple inclusion of a header file would cause otherwise working code to stop compiling. This compile command (same as above but with -D removed): g++ -c -g -Wall -fexceptions -I/path/to/boost-1.35.0/include main.cpp -o main.o runs to completion and the subsequent link is successful. Any ideas? Thanks in advance, Ken

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