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RBGL use with BGL minCut() function
by Gianni Loiacono 29 Jan '09

29 Jan '09

Hi all, sorry for my poor english. I want to use RBGL http://bioconductor.org/packages/2.3/bioc/html/RBGL.html into my project (I use BGL) for to use the function minCut() for to obtain the minimum cut and **the list of two subsets (S and V-S) cutted from the algorithm** (for me this is an import "thing"). I have readed all pdfs all docs, but I don't understand how I can use this library/dll in my project. Also, I have tried to add the sources files to my project (mincut.cpp, mincut.hpp, RBGL.hpp) and rebuild all, but the compiler don't find the Rdefines.h include file :°(. Please, somebody can help me with some example? I use C++ Mingw compiler and Code::block editor. Thanks a lot :-)

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Simple serialization of int*
by Sahrah 29 Jan '09

29 Jan '09

Hi all, I am looking for a solution to do this: int p1 = 5; int* test; test = &p1; std::ofstream out("test.bin"); boost::archive::binary_oarchive ar(out); ar << test; it does not compile. I get: Error 9 error C2228: left of '.serialize' must have class/struct/union c:\...\boost_1_37_0\boost\serialization\access.hpp I am using MSVC9. Boost 1.37.0 thanks, Sahrah -- View this message in context: http://www.nabble.com/Simple-serialization-of-int*-tp21713482p21713482.html Sent from the Boost - Users mailing list archive at Nabble.com.

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Boost.Asio 1.37 - can't compile with VC++ 2003 (version 1.35 is fine)
by lipik 29 Jan '09

29 Jan '09

Hi, I just upgraded my Boost distribution, and have immediately run into a compilation problem: both Intel and VC++ compilers complain that: - 'QueueUserAPC' : is not a member of 'operator``global namespace''' - 'QueueUserAPC': identifier not found, even with argument-dependent lookup 1.35 compiles fine. I checked and this API is available in Winbase.h. Can't figure out why it is not being found - there don't seem to be be any C++ version directives hiding it inside winbase. I am on XP, and _WIN32_WINNT is set to 0x0501, so this is not the culprit either. Pre-compiled headers are turned off, and I have defined WIN32_LEAN_AND_MEAN (to avoid winsock conflict). Any help greatly appreciated. Thanks Amit

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Function for Replace NaN with Zero and Vector2Vector Concordance
by Gundala Viswanath 29 Jan '09

29 Jan '09

Dear all, I have two questions: 1. What's the way in Ublas to replace Nan with Zero, be it in Vector or Matrix? 2. What's the way to check vector 2 vector concordance. E.g. vector <int> V1 += 1,2,3; vector <int> V2 + =1,2,3; if we do that_func(V1,V2), it will returns true. - Gundala Viswanath Jakarta - Indonesia

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Re: [Boost-users] Extending boost::function for mathematics?
by Jesse Perla 29 Jan '09

29 Jan '09

Thanks as always Stephen (who I still refuse to accept is either a single individual or human): Sorry to all if this is getting so long and specific, this project is justified later. Your comments generated a lot of thought about what my main problems are. I think I distracted myself by the generation of derivatives here before I had worked out some other issues. But your implementation looks very elegant. For now lets assume that people supply the gradient/jacobian directly or from their own finite_difference/autodifferentiation. So here are some, more basic, questions. Question 1: Based on your template, how do I forward a function to the boost::function's operator() in this wrapper? Why might we want to do this? Because we are trying to implement a concept with operator() and .gradient(..) with a function wrapper here. Library writers may want to write generic code that operates on any of these, not just ones wrapped in math_function... Then we may end up with true inlining of operator() and .gradient(...) when a full differentiable function object is implemented, instead of always going through an indirection pointer in boost::function. template<class Signature> class math_function { public: typedef boost::function<Signature>::result_type result_type; template<class F> math_function(const F& f, const G& f) : f_(f) : g_(g) {} result_type operator()(How to extract from the signature the input parameters? myvalues...) { return f_(myvalues....); } result_type gradient()(How to extract from the signature the input parameters???????) { return g_(myvalues...); } private: boost::function<Signature> f_; boost::function<Signature> g_; }; void test_mathfunctions() { using lambda::_1; using lambda::_2; math_function<double (double)> myfunc(_1*_1, 2* _1); //simple quadratic cout << myfunc(.1); cout << myfunc.gradient(.1); } Question 2: How can this wrapping interact with binding? void test_mathfunctions_binding() { using lambda::_1; using lambda::_2; //But you might also want a constant thrown in there... Why a separate parameter? Because you don't take the derivative over the other stuff. And you want to keep your functions pure so you can bind, not force them to be stateful, etc. math_function<double (double, double)> myfunc(_1*_1 + _2, 2* _1); //simple quadratic translated by a constant //But how would you work with bind? Would these following work immediately? boost::function<double (double)> myfunc_bound = bind(myfunc, _1, 2.0); boost::function<double (double)> myfuncderiv_bound = bind(myfunc::gradient, _1, 2.0); //or something like this... I always forget member function notation. //Any way to bind that entire structure back to a math_function? Very useful since we would bind parameters before calling optimizers, etc. With dynamic programming we usually have a grid of values and call the optimizer binding over the entire grid. math_function<double (double)> myfunc_bound = math_bind(myfunc, _1, 2.0); cout << my_func_bound.gradient(1.0); //Note that the binding can now use the gradient. } Question 3: How would we adapt a structure implementing the operator() and gradient() to be stored here? Just like boost::function accepting any function object? struct square { double operator()(double x) {return x * x;} double gradient(double x){return 2 * x;} }; math_function<double (double)> myfunc(square); Given the previous code, would we write a constructor like?: template<class F> math_function(const F& f) : f_(f), g_(bind(F::gradient, f, _1...?) //Here I don't see how to bind to the arbitrary signature, extracting the inputs from the Signature which (may) be more than 1 Question 3: What are the thoughts on whether/how this is extensible to higher dimensions? Lets start on the gradient with mapping functions: f : R^N -> R It is perfectly reasonable for these types of problems for the first parameter in the function to be the only one that the derivative is taken over. The dimensionality of the derivative/gradient/jacobian would come out of a combination of the result_type from the signature and the dimensionality of the domain. For example, something like: template<int DomainDim, class Signature> class math_function { public: typedef boost::function<Signature>::result_type result_type; typedef boost::array<DomainDim, result_type> gradient_result_type; //Note that this adds the dimensionality, the data structure could be a template parameter. template<class F> math_function(const F& f, const G& f) : f_(f) : g_(g) {} result_type operator()(How to extract form the signature the input parameters???????) { return f_(Signature); } gradient_result_type gradient()(How to extract form the signature the input parameters???????) { return g_(Signature); } private: boost::function<Signature> f_; boost::function<gradient result_type with OLD INPUT Signature> g_; }; void test_mathfunctions_multidim() { using lambda::_1; using lambda::_2; boost::array<double, 2> mygrad(boost::array<double, 2> x, double a) {boost::array<double, 2> ret; ret[0] = 2*x[0]; ret[1] = 2*x[1]; }; //I put this separately since I don't know how to construct arrays in lambda math_function<2, double (boost::array<double, 2> , double)> myfunc(pow(_1[0]*, 2) + pow(_1[1], 2) + _2, mygrad); cout << myfunc.gradient({{0.0, 0.0}}); //etc. } Question 4: Now lets say that what we really want is to manage f: R^N -> R^M functions. Here, we could potentially use ublas::matrix as a default data structure. template<class Signature, class SecondDimStructure = ublas::matrix, template <class T, int N> class NDimStructure = boost::multi_array > //We really don't need the dim's here since we are using heap based data structures. class math_function { public: typedef boost::function<Signature>::result_type result_type; typedef SecondDimStructure gradient_result_type; //This really is a jacobian, size N * M typedef NDimStructure<result_type::value_type, 4> hessian_result_type; //This really is size (N*M) ^2 if I remember my calculus.... template<class F> math_function(const F& f, const G& f) : f_(f) : g_(g) {} result_type operator()(How to extract form the signature the input parameters???????) { return f_(Signature); } gradient_result_type gradient()(How to extract form the signature the input parameters???????) { return g_(Signature); } private: boost::function<Signature> f_; boost::function<gradient result_type with OLD INPUT Signature> g_; //should add in the higher dimensional hessian of the function if I remember }; Question 5: I want to also associate information about the nature of the function. Whether it is convex/concave, increasing, strictly increasing, etc. These tend to have an inheritance structure, but it isn't absolutely necessary. I was thinking about using trait classes. But I assume that we would lose all those traits when we use type erasure? Are we better off storing a bunch of enums in this data structure? Increasing the size of the class shouldn't be an issue. Question 6: Let me justify why this is all very useful and a general problem: Right now, everyone writing non-linear algorithms in C++ has their own structures for managing mathematical functions that contain derivatives, jacobians, hessians. I am running into this right now because I am trying to wrap a bunch of other people's algorithms for my own work. A few comments: 1) Everyone is using dynamic polymorphism for these overloading a virtual operator() and some type of gradient/jacobian... I assume this is because there is no agreed upon concept for functions objects with gradients... In reality, none of these seem to require dynamic polymorphism. Why shouldn't a newton's method optimizer have inlining of the operator() and derivative through static polymorphism where possible? 2) Most of these guys have conflated functionality/settings specific to their optimizers/solves with the evaluation of the function/gradient. This makes generic code difficult without wrappers/adapters. 3) Many use their own data structures for arrays, matrices, multidim results. This may be inevitable, but means that you need to have these types parameterized in any mathematical callback routine. 4) While a lot could be gained from having people agree on a static concept for mathematical applications akin to standardizing on operator() for functors, it is also very useful to have a generic callback wrapper akin to boost;:function. The main reason for this is that you will tend to write parameterized, pure functions where you want to bind parameters. Worst case, people could write their own functions with this mathematical callback structure and adapters could be written for the different libraries. 5) Not to disparage these superb libraries, but a few examples to see what I mean: http://quantlib.org/reference/class_quant_lib_1_1_cost_function.html and http://trilinos.sandia.gov/packages/docs/r6.0/packages/didasko/doc/html/nox… and http://www.coin-or.org/CppAD/Doc/ipopt_cppad_simple.cpp.xml If anyone is interested in working with me on this very interesting and useful problem, please give me an email. I think it has a lot of potential for general use. -Jesse

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Re: [Boost-users] Boost and K-Cuts
by Gianni Loiacono 29 Jan '09

29 Jan '09

Hi mr. Zeljko Vrba, I have downloaded and readed the soruce file for build the GoHu tree. It uses a different implement approch from Boost....;°( I don't understand very well the source, but I have understand that if I want to add it to my project I must "revolutionize" my source :( :( Sorry for my eng. ;) Bye.

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Re: [Boost-users] top posting, was boost::proto helpful for a compiler project?
by raindog＠macrohmasheen.com 29 Jan '09

29 Jan '09

I know its a rule, but I think it is dumb. My phone does not even support botting posting for example, does that mean I'm not allowed to post to this newgroup? my guess is that it started off with a few people wanting to separate themselves from others by usage of arbitrary rules in order to obtain some form of "l33tn3$$" without having actually considering the merits or lack thereof ubtil after their motives were question in which scenario artificial ones were created to support the habbit. Modern mail clients (my phone not one of them) support threaded mail anyways and so what you get is the same email. 100 times in a thread. There has been the argument that if you were ob a forum that they go by bottom posting but again modern mail clients support threading anyways, and I don't know about you, but I can't recall the last time I was reading a forum and every post included included the entirety of the posts to the thread prior. Lastly, why would you ever want to pick up a thread by reading the middle of it? Using the forum analogy, one would be hard pressed to find someone whose month was to always read a thread by starting on page 12, so, group by thread and read from the start ------Original Message------ From: Eric Niebler Sender: boost-users-bounces(a)lists.boost.org To: boost-users(a)lists.boost.org ReplyTo: boost-users(a)lists.boost.org Sent: Jan 26, 2009 4:42 PM Subject: Re: [Boost-users] boost::proto helpful for a compiler project? Please don't top-post. See http://www.boost.org/community/policy.html#effective peter_foelsche(a)agilent.com wrote: > Eric Niebler wrote: >> peter_foelsche(a)agilent.com wrote: >>> How can boost proto help me in my compiler project? >>> >>> Is it another way to write a grammar and parse it? >> >> If by "compiler" you mean something that reads a text file, parses >> it according to a grammar and Does Something, then Proto is *not* >> what you are looking for. Use Boost.Spirit. >> > ok. Can you give me an application area for boost::proto? In short I > don't understand what DomainSpecificEmbeddedLanguage means. The term is defined in Proto's documentation, and many examples are given there. http://boost-sandbox.sf.net/libs/proto HTH, -- Eric Niebler BoostPro Computing http://www.boostpro.com _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users Sent from my Verizon Wireless BlackBerry

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Boost.Parameters: are static member functions possible somehow?
by Joost Kraaijeveld 28 Jan '09

28 Jan '09

Hi, I can generate global and ordinary member functions with Boost.Parameters. But I would like to create static member functions. IS that somehow possible? I have looked at the macros of the library but I did not get any wiser :-(. So is it possible, and if so, how? TIA -- Groeten, Joost Kraaijeveld Askesis B.V. Molukkenstraat 14 6524NB Nijmegen tel: 024-3888063 / 06-51855277 fax: 024-3608416 web: www.askesis.nl

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Install on Mac OS
by rolf ngondo 28 Jan '09

28 Jan '09

Hi all! I'm developping an application using boost on MAC OS X, using CMake as system compiler. I succesfully built the same application with CMake on windows and it works fine. But on Mac OS, the build fails. It sounds like CMake failed finding boost include directory. I tried the bjam command : bjam --builddir=anydir --toolset=gcc --with-some_boost_lib install. I got libs but it skipps creating any directory on /usr/local/. If anyone succeeded on installing boost properly in /usr/loal... please help. One more thing, since I'm using CMake, I can't use boost version later than 1.36.0. Thanks to all.

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[BGL] - deriving from filtered_graph
by Michael Fawcett 28 Jan '09

28 Jan '09

When using a type that I derived from filtered_graph, if I use operator[] on the instance, e.g. derived_from_filtered_graph_instance[descriptor].foo = bar; I get the following error: C:\dev\vendor\boost\1.37.0\boost/graph/graph_traits.hpp(124) : error C2039: 'edge_bundled' : is not a member of 'btra::restricted_graph<Graph>' 1> with 1> [ 1> Graph=btra::undirected_graph 1> ] 1> C:\dev\vendor\boost\1.37.0\boost/graph/graph_traits.hpp(137) : see reference to class template instantiation 'boost::edge_bundle_type<G>' being compiled 1> with 1> [ 1> G=btra::restricted_graph<btra::undirected_graph> 1> ] 1> C:\dev\btra\trunk\btra/two_way/esri_io.h(186) : see reference to class template instantiation 'boost::graph::detail::bundled_result<Graph,Descriptor>' being compiled 1> with 1> [ 1> Graph=btra::restricted_graph<btra::undirected_graph>, 1> Descriptor=boost::detail::edge_desc_impl<boost::undirected_tag,__w64 unsigned int> 1> ] and if I typedef edge_bundled in the derived class, everything seems to work okay. filtered_graph doesn't contain the typedef, the Graph type does, so does this mean that to be more correct I should specialize graph_traits for my derived type, or is just having the typedef enough? Also, in the filtered_graph documentation, it says it models VertexAndEdgeListGraph and PropertyGraph, but neither of those concepts mention edge_bundled as an associated type. Thanks in advance, --Michael Fawcett

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