March 2013 - Boost-users - lists.preview.boost.org

[boost::Statechart] posting a "serial timeout" event
by Andre de Jong 25 Mar '13

25 Mar '13

I've been using boost's asynchronous statechart to write a program. In this program I communicate with another device using an asynchronous serial port. I have a state that waits for a confirmation from the device over the serial port and then posts a "confirmation received" event. This works well but, I would also like to implement a "timeout" event. In previous programs I had been using switch case statements for my state machines where I had code that could be run each time the loop was run. This meant I could run code and check if I should change state due to something timing out. Like this: while(1){ switch (state){ case 0:{ sendMessage(); state = 1; sendTime = boost::chrono::steady_clock::now(); } break; case 1:{ if (isConfirmationReceived()){ // do something state = 2; } else if (boost::chrono::steady_clock::now() > start + boost::chrono::duration<double>(WAIT_LENGTH)){ //do something state = 3; } } break; // etc etc } } How would I implement something like this using boost::StateChart? Or, should i be thinking about this a completely different way?

1 0

Re: [Boost-users] Broken Links?
by Boost_mailinglist＠gmx.de 25 Mar '13

25 Mar '13

Hello, you can see the directory listing of the pictures under http://www.boost.org/doc/libs/1_53_0/libs/pool/doc/images/ -----Ursprüngliche Nachricht----- Gesendet: Montag, 25 März 2013 um 06:32:27 Uhr Von: "Hei Chan" <structurechart(a)yahoo.com> An: "boost-users(a)lists.boost.org" <boost-users(a)lists.boost.org> Betreff: [Boost-users] Broken Links? Hi, On�http://www.boost.org/doc/libs/1_53_0/libs/pool/doc/html/boost_pool/pool/…, all the graphs there seem broken. Anyone fixing it? Thanks in advance. Cheers, Hei _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

1 0

bad reloc address when compiling with mingw
by Leonardo Sá 24 Mar '13

24 Mar '13

Hi all, I have been trying to create an .exe that links to several boost libraries (date-time, python, etc.) using MinGW, cross compiling for windows on linux. I compiled boost using mingw without problems. When linking the exe, I am receiving the following error: CMakeFiles/fp_core_test.dir/objects.a(MockEnvironment.cpp.obj):MockEnvironment.cpp:(.text+0x381): undefined reference to `fp_core::Window::init(int, int, boost::shared_ptr<fp_core::Renderer>)' /usr/bin/i686-w64-mingw32-ld: CMakeFiles/fp_core_test.dir/objects.a(MockEnvironment.cpp.obj): bad reloc address 0x8 in section `.text$_ZN5boost6detail15sp_counted_baseC2Ev[boost::detail::sp_counted_base::sp_counted_base()] I have no idea what "bad reloc address" means. Googling wasn't much help. Anyone can give me a pointer in the right direction? Thanks!

1 0

newbie problem with Program Option string value
by Neil Sutton 24 Mar '13

24 Mar '13

I am having problems getting a program option to work. The option should enable a user to enter a location when they select the '--location' option. so, if you type --location canada, the code should store the supplied string - canada and pass it on to the program. This is a typical program option with nothing special. But I cannot seem to get it to work! Please look at this: ---------------------------------------------------- std::string place_option; // a global variable po::options_description general("General options"); general.add_options() ("location", po::value<std::string>(), "location of your home"); // there are other non string options po::variables_map vm; po::store(po::parse_command_line(ac,av, general),vm); po::notify(vm); if(vm.count("help")) { std::cout << general << "\n"; return 0; } if(vm.count("version, v")) { std::cout << "version aplha\n"; } if(vm.count("location")) { place_option = vm["location"].as<std::string>(); // should pass the string value entered at command line to std::string place. } If i run my program with eg 'myprogram --location disney' I get: terminate called after throwing an instance of 'std::logic_error' what(): basic_string::_S_construct NULL not valid Aborted ------------------------------ Now I have tried a few variations of the code. The examples show where an int value is supplied and retrieved. I cannot work out how to do - what should be very trivial. I simply want to recover the value associated with 'location' i.e a std::string entered at the command line. I then want to pass that value on to my program to do something with it. I do not understand the error. Can someone kindly show me the correct syntax to accomplish this please? Kind regards.

3 2

[iostreams] mapped_file path issue
by Alexandre 24 Mar '13

24 Mar '13

Hello, After reading through all the documentation and examples I could read, I still can't get the following piece of code to work . I assume that when you pass a new_file_size and a path to the mapped_file_params class , it will then open the file at the location desired when I call the constructor of mapped_file with the mapped_file_params object in parameter. But the only thing it does is to create a file with a weird name , like "%F8/134" in the project working directory, not where I told it to. Maybe I'm wrong and one should create file before specifying it to the mapped_file? After reading the doc, I was under the assumption that it created a new file when you fill in the new_file_size param. and specifies the filename. Anyone experienced this before? Any advice on how to resolve this? Here's the code: boost::iostreams::mapped_file_params param(filename); // filename is a std::string with the correct path param.flags = boost::iostreams::mapped_file::mapmode::readwrite; param.new_file_size = sizeNeeded; // sizeNeeded is the size of the data param.length = sizeNeeded; boost::iostreams::mapped_file fileMap(param); // at this point the file is created … Thanks for your time, Alexandre

1 0

[BGL] boost::disjoint_set getting new representative after link()
by Adi Shavit 23 Mar '13

23 Mar '13

Hi, I'm using boost::disjoint_sets_with_storage<>. After calling link(rep1, rep2), I want to know the new rep - the representative of the merged set. Obviously, I can call find_set(rep1) to find it. I assume that the extra call to find_set incurs an additional run-time cost per call to link. Is this true or is the call immediate (as in returning the immediate parent of rep1)? If it does incur a run-time cost, then we know that the new-rep is *either *rep1 or rep2. Is there some other way to know which one it is? On a related matter, I am also tracking the *size *of the sets for each link(). Does knowing the size of the rep set before the link help in determining which of rep1 or rep2 will be the new rep? Is there a simple way to extend boost::disjoint_sets_with_storage<> to do the size tracking internally (currenlty I keep an external size vector per rep to keep track of the link()s). Thanks, Adi

2 2

erase and put methods in property tree lib of boost
by Sashidhar Guntury 23 Mar '13

23 Mar '13

I have been trying to use the put and erase methods in boost's property tree library with very limited success. I have tried to go through the documentation but it seems really esoteric with no real example to demonstrate. This is what I would like to do - I have a json object. I look for a particular key (call it "title") and extract the corresponding value (call it "Eric Clapton"), do something with "Eric Clapton" (say change it to "ec") insert it in the place of the old value. Now, should I do an "erase" to remove the previous entry and then "put" the new pair? Will "put" replace the old value? void doSomething(const ptree& node) { ... BOOST_FOREACH(const ptree::value_type& child, node.get_child("artists")) { string text = child.second.get<string>("title"); // do something to the text to give text2 child.second.put("title", text2); } ... } The above code gives an error which is equally hard to understand. I was hoping someone would shed some light. thanks Sashidhar

2 2

[BGL] Error C2679 when inserting edge property to subgraph
by Nicholas Mario Wardhana 22 Mar '13

22 Mar '13

Hi all, Could somebody tell me how to add a bundled edge property for subgraph, please? The code, based on [1], is as follows. // code starts #include <boost/config.hpp> #include <boost/graph/subgraph.hpp> #include <boost/graph/adjacency_list.hpp> #include <boost/graph/graph_utility.hpp> using namespace std; using namespace boost; struct VertexProperty { int intValue; }; struct EdgeProperty { std::size_t biconnected_component; int intValue; }; typedef adjacency_list<vecS, vecS, undirectedS, VertexProperty, property<edge_index_t, int, EdgeProperty> > PlainGraph; typedef subgraph<PlainGraph> Graph; int main(int argc, char* argv[]) { PlainGraph g1; Graph g(2); VertexProperty v0; v0.intValue = 1; VertexProperty v1; v0.intValue = 1; EdgeProperty e; e.biconnected_component = 0; e.intValue = 0; add_edge(0, 1, g); put(get(vertex_bundle,g), 0, v0); // OK put(get(vertex_bundle,g), 1, v1); // OK put(get(edge_bundle,g), 0, e); // error here return 0; } // code ends The error is as follows: // error starts 1>D:\API\boost_1_53_0\boost/property_map/property_map.hpp(361): error C2679: binary '[' : no operator found which takes a right-hand operand of type 'int' (or there is no acceptable conversion) 1> D:\API\boost_1_53_0\boost/graph/subgraph.hpp(797): could be 'EdgeProperty &boost::subgraph_global_property_map<GraphPtr,PropertyMap,Tag>::operator [](boost::detail::edge_desc_impl<Directed,Vertex>) const' 1> with 1> [ 1> GraphPtr=boost::subgraph<PlainGraph> , 1> PropertyMap=boost::adj_list_edge_property_map<boost::undirected_tag,EdgeProperty,EdgeProperty &,unsigned __int64,boost::property<boost::edge_index_t,int,EdgeProperty>,boost::edge_bundle_t>, 1> Tag=boost::edge_bundle_t, 1> Directed=boost::undirected_tag, 1> Vertex=unsigned __int64 1> ] 1> while trying to match the argument list '(const boost::subgraph_global_property_map<GraphPtr,PropertyMap,Tag>, int)' 1> with 1> [ 1> GraphPtr=boost::subgraph<PlainGraph> , 1> PropertyMap=boost::adj_list_edge_property_map<boost::undirected_tag,EdgeProperty,EdgeProperty &,unsigned __int64,boost::property<boost::edge_index_t,int,EdgeProperty>,boost::edge_bundle_t>, 1> Tag=boost::edge_bundle_t 1> ] 1> main.cpp(74) : see reference to function template instantiation 'void boost::put<boost::subgraph_global_property_map<GraphPtr,PropertyMap,Tag>,EdgeProperty&,int,EdgeProperty>(const boost::put_get_helper<Reference,LvaluePropertyMap> &,K,const V &)' being compiled 1> with 1> [ 1> GraphPtr=boost::subgraph<PlainGraph> , 1> PropertyMap=boost::adj_list_edge_property_map<boost::undirected_tag,EdgeProperty,EdgeProperty &,unsigned __int64,boost::property<boost::edge_index_t,int,EdgeProperty>,boost::edge_bundle_t>, 1> Tag=boost::edge_bundle_t, 1> Reference=EdgeProperty &, 1> LvaluePropertyMap=boost::subgraph_global_property_map<boost::subgraph<PlainGraph> ,boost::adj_list_edge_property_map<boost::undirected_tag,EdgeProperty,EdgeProperty &,unsigned __int64,boost::property<boost::edge_index_t,int,EdgeProperty>,boost::edge_bundle_t>,boost::edge_bundle_t>, 1> K=int, 1> V=EdgeProperty 1> ] 1> // error ends I found a few other threads [2, 3] about this, but their solutions don't solve the problem. BTW I use Visual Studio 2010 on Windows 7 64-bit. The Boost version is 1.53.0. Thank you! Best regards, Nicholas Mario Wardhana References: [1] http://boost.2283326.n4.nabble.com/BGL-Bundled-Properties-in-subgraphs-td25… [2] http://stackoverflow.com/questions/7608031/boost-subgraph-and-bundled-prope… [3] https://groups.google.com/forum/?fromgroups=#!topic/boost-list/5EIkKybaUTY

2 2

[boost][units]: Looking for more elegant ways to define RPM and velocity[km/h]
by Dennis Gertitschke 22 Mar '13

22 Mar '13

2 1

Martin Lester : 3/22/2013 4:03:04 AM
by Martin Lester 22 Mar '13

22 Mar '13

http://www.sanjose-personalinjuryattorney.com/btjh/bdmm.aabn Martin Lester 3/22/2013 4:03:04 AM

1 0