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[Review Report] ODEInt accepted
by Steven Watanabe 04 Oct '12

04 Oct '12

AMDG The review of the ODEInt library submitted by Mario Mulansky and Karsten Ahnert ended last Friday. Many thanks to everyone who participated in this review. The library is ACCEPTED into Boost unconditionally. Summary: 7 ACCEPT 1 ABSTAIN Reviews: http://lists.boost.org/Archives/boost/2012/09/196733.php http://lists.boost.org/Archives/boost/2012/09/196882.php http://lists.boost.org/Archives/boost/2012/09/196883.php http://lists.boost.org/Archives/boost/2012/10/196966.php http://lists.boost.org/Archives/boost/2012/10/196965.php http://lists.boost.org/boost-users/2012/09/76089.php http://lists.boost.org/boost-users/2012/09/76058.php http://lists.boost.org/boost-users/2012/09/76069.php Other comments: http://lists.boost.org/Archives/boost/2012/09/196756.php The reviews were overwhelmingly positive. Most reviewers were satisfied with the library documentation and interfaces. Issues: These were points brought up by reviewers. The authors are free to accept or reject any of these at their discretion. - A number of minor documentation corrections. - Automatically deduce the correct algebra from the state type. - Use a default initial step size. - Allow breaking out of the algorithms In Christ, Steven Watanabe

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Re: [Boost-users] [odeint] Can odeint integrate a 2-dimensional function?
by Karsten Ahnert 04 Oct '12

04 Oct '12

On 10/04/2012 03:28 PM, Rob Conde wrote: > Say I have an equation that is a function of x and y...can I use odeint to > integrate this function over a 2-d region (i.e. a square or a circle, etc.)? > If so, are there any examples of this? I don't think this is possible. This sound like integration of a known function. Odeint is devoted to solve ordinary differential equations. Karsten

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[process] how to suggest bugs/fixes for boost.process?
by Brian Budge 04 Oct '12

04 Oct '12

Hi all - I've started using boost.process despite the fact that it is not an official boost library. I've founds some cases that don't compile or give warnings, and I'd like to log a bug with possible fixes somewhere. Given that the library is not officially in boost, how should I go about this? Thanks, Brian

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Moving an std::string into a boost::thread in C++03
by Adi Shavit 04 Oct '12

04 Oct '12

Hi, I'm using boost 1.51 on multiple platforms and compilers without C++11. In my main thread, I have a very long, expensive to copy, std::string veryLongString, that I need to pass to a new thread for processing. After the new thread is created I have no more use for veryLongString, hence I'd like to *move *it into the boost::thread ctor. Obviously, if veryLongString was created as a shared_ptr<std::string> then I could just *copy* the shared_ptr into the thread ctor, but it wasn't, so I'd need to copy it anyway. How can I [boost::]move() veryLongString into the boost::thread ctor (probably using via boost::bind)? Is this possible? Thanks, Adi

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Re: [Boost-users] [asio] Custom asynchronous service
by Marat Abrarov 04 Oct '12

04 Oct '12

Hi Acer, > I would like to adapt my class to asio for offering > async_do_something(param, callback) interfaces. http://sourceforge.net/projects/asio-samples/ especially (SVN): https://asio-samples.svn.sourceforge.net/svnroot/asio-samples/trunk/include… https://asio-samples.svn.sourceforge.net/svnroot/asio-samples/trunk/include… or https://asio-samples.svn.sourceforge.net/svnroot/asio-samples/trunk/include… https://asio-samples.svn.sourceforge.net/svnroot/asio-samples/trunk/include… > After reading examples presented in asio/examples/services/ and some asio > source code. > > I found the example does not do invoke callback stuff (e.g. > asio/examples/service/logger_service.cpp). > > In case of asio source code, there are classes such as > detail::wait_handler<> that wrap user callbacks for invoked later. It's not a wrapper for deferred invocation. Here's my implementation of handler parking (Asio custom memory allocation and custom invocation strategy are supported): https://asio-samples.svn.sourceforge.net/svnroot/asio-samples/trunk/include… Regards, Marat Abrarov.

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[BGL] vecS for vertex container and vertex index adjustments
by Sergey Mitsyn 03 Oct '12

03 Oct '12

Hi all, I know that while using vecS for vertices one has no vertex iterator stability upon removing vertices. But I have a question if there exists something like vertex _index_ stability. The documentation says that indices for vertices are automatically adjusted so that they are still in contiguous range, but it is not specified how it is done. Is it okay to assume that if a vertex with an index I is removed, then vertices with indices < I have their indices unchanged, while vertices with indices > I have their indices decreased by one? The actual problem is removing all vertices meeting some condition. Is the following code ok? // traverse all vertices and remove those for which predicate // condition_to_remove_vertex returns true. // graph is adjacency_list<.., vecS, ...> vertex_iterator vi = vertices(graph).first, vi_end = vertices(graph).second; while (vi != vi_end) { if (condition_to_remove_vertex(vi, graph)) { vertices_size_type end_index = vertex_index[*vi_end] , vi_index = vertex_index[*vi]; remove_vertex_f(*vi, graph); // vi and vi_end are invalid --end_index; vi = vertices(graph).first + vi_index; vi_end = vertices(graph).first + end_index; // now vi and vi_end are valid again } else ++vi; } This way seems to be more effective than to start iteration again every time a vertex is removed. ------------ Sergey Mitsyn.

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C++ (boost) library for serial port communication
by Alexander Dietz 03 Oct '12

03 Oct '12

Hi all, I wonder if there is a boost-library that enables easy and robust communication to a serial port, just as e.g. the python library pyserial does. Maybe there is a boost-library which can be used for those purpose instead of implementing my own C-style classes and functions? Thanks a lot, Alex

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A couple of odeint questions
by Tiago Gehring 02 Oct '12

02 Oct '12

Hello, I've been using the odeint library for some time now - and I really like it, thanks for the great work! I know that the odeint library is currently being reviewed but I'm actually writing here to ask a couple of questions about my usage scenario, hope that I'm in the right place. My usage scenario involves neural networks where I have a set of n equations for the N neurons themselves and another m equations for all the M synapses (connections) where usually M >> N and the two sets of equations depends on each other. What I'm trying to do is to put all these N + M equations into one large system and to integrate them at once while also keeping the state vectors separated. This is because of the different dimensionality of the two sets of equations and because my intention is to later use OpenCL to do the calculations (which as I understand works better if you use something like a vexcl::multivector<double, M> + another vexcl::multivector<double N> and I don't see how to pack all of this in one large state vector); So my first question is: can I somehow "combine" two sets of state vectors into one thing or integrate two systems in parallel (synchronously)? I tried the former (one combined state object) and even defined my own combined algebra (a std::pair of std::vectors - later vexcl::multivectors) but then stumbled into problems with my value type (which I defined as a std::array<double, 2>). It seems that I have to define all possible mathematical and comparison operations for my pairs (arrays). And my second question: my problem involves integrating the system until one of the neurons fires - at which point it's state variable (membrane potential) jumps to a fixed value, i.e., I have a sharp discontinuity in the state variable. My way of dealing with this right now was to implement a custom integration function (based on the adaptive integration one) which has a built in function that checks if the threshold was reached at every integration step. When this happens I break the integration, reset the state of the neuron in question to the fixed value and start integrating again. I wonder if it's possible to solve this in an easier way... Is it possible for example to change the state on the fly and can the system handle discontinuities? (i.e. can I integrate without stopping each time a neuron fires). Thanks a lot, Tiago

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lisp like operetor collection on well kown C++ data structure
by Niitsuma Hirotaka 02 Oct '12

02 Oct '12

I wrote scm2cpp.hpp https://github.com/niitsuma/scm2cpp.hpp/blob/master/scm2cpp.hpp scm2cpp.hpp is lisp like operetor collection on well kown C++ data structure lisp function car cdr cons list-ref set-car! .. etc can use for std::vector std::list boost::ptr_list boost::fusion::list and std::pair is regard as cons example usage https://github.com/niitsuma/scm2cpp.hpp/blob/master/usage.cpp https://github.com/niitsuma/scm2cpp.hpp/blob/master/list-test.cpp Also eq? eqv? equal? quote symbol functions are implemented. plz see usege https://github.com/niitsuma/scm2cpp.hpp/blob/master/equal-test.cpp eq? function implimeted as direct addrest comparison template<typename T> bool is_eq(T & x, T & y) {return (&x)==(&y);} thus cons(T, std::list<T>) becomes boost::ptr_list<T> All lisp like operator keep same address for same object.

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[Build] configure files copied into stage directory
by Alexander Khomyak 01 Oct '12

01 Oct '12

Hi. I build library binaries from source using build system. And now the system copies dll and lib-files into stage directory. But I also need to copy pdb-files. How to configure the build system to do so? Regards, Alexander Khomyak

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