- Boost-users - lists.boost.org

[ptr_container] view_clone_allocator with associative containers
by Matthias Vallentin 01 Mar '10

01 Mar '10

I cannot get the view_clone_allocator to work with associative containers, as in the example below: boost::ptr_vector<int> vec; boost::ptr__map<std::string, int, boost::view_clone_allocator> map; int* i = new int(42); vec.push_back(i); std::string k("foo"); map.insert(k, i); >From the error message, it seems that the CloneAllocator is still of type boost::heap_clone_allocator. Why is this failing? It seems intuitive to specify the allocator as third parameter, similar to the example with ptr_vector where the allocator is the second argument. Matthias -- Matthias Vallentin vallentin(a)icsi.berkeley.edu http://www.icir.org/matthias

2 2

array definition
by Damien MATTEI 01 Mar '10

01 Mar '10

hello, i have this definition that works: array_2D_double psf_cartesian_centered(boost::extents[range_ext(indiceBegin,indiceEnd+1)][range_ext(indiceBegin,indiceEnd+1)]); but i want to use this writing to improve reading of my code in a more natural way: array_2D_double psf_cartesian_centered2[ boost::indices[indiceBegin <= array_2D_double::index_range() < indiceEnd][indiceBegin <= array_2D_double::index_range() < indiceEnd] ]; unfornunately this does not work , i read one hundred times the boost tutorial and documention qhere it is written something like this should ... what is my error? regards, damien

1 0

Have Boost random Library contained the function for generating Gaussian noise ? Can any one with kindness help me?
by fmingu 01 Mar '10

01 Mar '10

I am a new comer and using Boost library for math works. I want to know whether Boost Random Library contained the function for generating Gaussian noise. Or Gaussian noise can be easily generated by the functions in Boost Random Library? Or any other library compatible with the Boost Random Library? Can any one with kindness help me?

2 1

best boost cc-mode style
by Russell L. Carter 01 Mar '10

01 Mar '10

Hi folks, I'm starting to get heavy into templates and it seems my ancient cc-mode customizations are a disaster when trying to format complicated template code. I'm now using emacs23 with cc-mode version 5.31.7. What's the best out-of-the-box cc-mode style for boost style template formatting? (Some googling revealed that Dave A. a long time ago made some mods to cc-mode, what style did they end up in?) tnks, Russell

1 0

[Exceptions] Custom type in error_info value?
by Andrew Chinkoff 01 Mar '10

01 Mar '10

This is the test program I would like to be explained to me: #include <iostream> #include <string> #include <boost/exception.hpp> struct MyException: virtual boost::exception{ }; class MyClass { char* s; public: MyClass(const char* msg) : s(strdup(msg)){ } MyClass(const MyClass& c){ s = strdup(c.s); } ~MyClass(){ free(s); } }; void main() { MyException ex; ex << boost::error_info<struct my_tag1, MyClass>("qweqwe"); ex << boost::error_info<struct my_tag2, std::string>("asdasd"); std::cout << boost::diagnostic_information(ex); } This is the program output: > Throw in function (unknown) > Dynamic exception type: struct MyException > [PAUmy_tag1@?1?main@] = [ type: ?AV?$error_info@Umy_tag1@?1?main@VMyClass @@@boo > t@@, size: 8, dump: 50 69 10 01 b8 18 7f 00 ] > [PAUmy_tag2@?1?main@] = asdasd So, my question: what should I do with 'MyClass' to see the output like this: > Throw in function (unknown) > Dynamic exception type: struct MyException > [PAUmy_tag2@?1?main@] = qweqwe (Wow !!! Terrible dump is replaced with readable string here !!!???) > [PAUmy_tag2@?1?main@] = asdasd Thanks, Andrew.

2 2

boost test: How to make boost test a friend ?
by Avi Bahra 01 Mar '10

01 Mar '10

I am looking into boost test. I dont not want to expose some member functions as public. However I need to access them for testing, is there any way making boost test a friend of this class ? Any help appreciated. Best regards, Ta, Avi

3 2

asio guidance
by Paul Dugas 28 Feb '10

28 Feb '10

I'm writing code to implement an existing communication protocol that uses a packet with a fixed header and variable payload (depending on a header field). I started using a previously recorded file and fstream::read() calls; i.e. read(buf,1) looking for the start-of-packet, read(buf, HEADER_LEN), extract the payload size and read the remainder. I am now looking to hook up the receiver logic to the actual gear and need to handle timeouts and such. I'm new to asio but it looks like what I may need given that I have to support device connections via serial ports and sockets but I also need to retain the ability to read from files. I'm wondering if anyone could suggest an approach to support all three comm schemes with the same packet reception logic. The idea would be for the receive routine to return message pointers or throw on timeouts or partial packets Paul

3 3

[lambda]
by Marcin Zalewski 28 Feb '10

28 Feb '10

I am trying to use lambda's constructor [1] with fusion's fused [2]. Fused requires that the function object passed to it has a following valid expression: boost::result_of< F(T1 ...TN) >::type Unfortunately, constructor does not support result_of. Its implementation contains the following piece of code: template <class U> struct sig { typedef T type; }; This happens to be exactly what's necessary for constructor to support result_of, but sig would have to be renamed to result. I guess I do not really have a question here but rather a request to make constructor compatible with result_of. There seems to be no reason not to do it, and I could not figure out a much nicer way to construct objects with fusion sequences than combining lambda's constructor and fusion's fused. It comes so close, but if only sig was result... Cheers, Marcin [1] http://www.boost.org/doc/libs/1_42_0/doc/html/lambda/le_in_details.html#lam… [2] http://www.boost.org/doc/libs/1_42_0/libs/fusion/doc/html/fusion/functional…

4 9

Problems with property_maps
by Trevin Murakami 28 Feb '10

28 Feb '10

Hello all. I'm having issues getting property maps to work properly with my custom adjacency_list. Here's a snippet of the code: // Definitions // define some of the properties the graphs will have // http://www.boost.org/doc/libs/1_42_0/libs/graph/doc/using_adjacency_list.ht… struct posx_t { typedef vertex_property_tag kind; }; struct posy_t { typedef vertex_property_tag kind; }; typedef property<posx_t, int> VertexPosX; // chain to add in posy typedef property<posy_t, int, VertexPosX> VertexPos; // chain to add in vertex_index typedef property<vertex_index_t, int, VertexPos> VertexProperty; // define our special graph typedef adjacency_list<listS, listS, undirectedS, VertexProperty, property<edge_weight_t, int> > AGraph; ... template<class T> void boostToVAGraph(const AGraph & g, const int num_nodes, const int num_edges, T ** idata, T ** odata, unsigned int ** segment_descriptor, unsigned int ** cross_pointers, unsigned int ** head_flags, T ** reference, const testrigOptions & testOptions) { typedef AGraph Graph; // define the manipulator for our special properties // http://www.boost.org/doc/libs/1_42_0/libs/graph/doc/using_adjacency_list.ht… // requires property_map.hpp // BROKEN!!!!! property_map<AGraph, posx_t>::type getposx = get(posx_t(), g); property_map<AGraph, posy_t>::type getposy = get(posy_t(), g); ... I used another function to generate the AGraph and apply values. And using property map there seems to work. However, I then pass it to this function using: boostToVAGraph(g, num_nodes, num_edges, idata, odata, segment_descriptor, cross_pointers, head_flags, reference, testOptions); On compile, I get this error: 1>agraph.cpp 1>c:/Documents and Settings/All Users/Application Data/NVIDIA Corporation/NVIDIA GPU Computing SDK/C/src/test/agraph.cpp(94) : error C2440: 'initializing' : cannot convert from 'boost::adj_list_vertex_property_map<Graph,ValueType,Reference,Tag>' to 'boost::adj_list_vertex_property_map<Graph,ValueType,Reference,Tag>' 1> with 1> [ 1> Graph=AGraph, 1> ValueType=int, 1> Reference=const int &, 1> Tag=posx_t 1> ] 1> and 1> [ 1> Graph=AGraph, 1> ValueType=int, 1> Reference=int &, 1> Tag=posx_t 1> ] 1> No constructor could take the source type, or constructor overload resolution was ambiguous Ideas? -Trevin "new to Boost" Murakami

2 2

[Review] ITL review extended until March 7th
by Hartmut Kaiser 28 Feb '10

28 Feb '10

Hey all, After getting the approval from our review wizards we decided to extend the review period of Joachim Faulhabers ITL library until March 7th, 2010. That should give everybody some more time to finish their reviews. Regards Hartmut --------------- Meet me at BoostCon www.boostcon.com

1 0