October 2007 - Boost-users - lists.preview.boost.org

Problem in calculating cycle sequence...
by abhishek.v＠tcs.com 01 Oct '07

01 Oct '07

Hi I m able to calculate whether the cycle exist in the graph or not. With the help of following code.. //Finding out cycles struct cycle_detector : public dfs_visitor<> { cycle_detector( bool& has_cycle, int& num):_has_cycle(has_cycle),cycle(num) { } template <class Edge, class Graph> void back_edge(Edge, Graph&) { cycle++; _has_cycle = true; } protected: bool& _has_cycle; int& cycle; }; int main () { ...... .... .... //Finding out whether the graph has cycles.. bool has_cycle = false; int count_cycle=0; typedef Traits::vertices_size_type size_type; cycle_detector vis(has_cycle,count_cycle); boost::depth_first_search(g, visitor(vis)); if(has_cycle) { file_op << "\nThe graph is cyclic"<< std::endl; file_op<<"\nNumber of cycles in the graph is "<<count_cycle; } else std::cout << "The graph is acyclic"<< std::endl; return 0; } Now what i want is to calculate the vertex between which the cycle exist ... How to calculate that.. Thanks Abhishek Vyas Tata Consultancy Services Mailto: abhishek.v(a)tcs.com Website: http://www.tcs.com ____________________________________________ Experience certainty. IT Services Business Solutions Outsourcing ____________________________________________ =====-----=====-----===== Notice: The information contained in this e-mail message and/or attachments to it may contain confidential or privileged information. If you are not the intended recipient, any dissemination, use, review, distribution, printing or copying of the information contained in this e-mail message and/or attachments to it are strictly prohibited. If you have received this communication in error, please notify us by reply e-mail or telephone and immediately and permanently delete the message and any attachments. Thank you

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string_algo no replace_if
by gast128 01 Oct '07

01 Oct '07

Dear all I was requesting an 'erase_if' a while ago, and now I ran into a 'replace_if' problem. So after spendig 2 hours in the documentation, I finally found on www ('[string_algo] replace repeated char with single instance?') that one should use the 'find_format_all': boost::find_format_all(str, boost::token_finder(boost::is_any_of("ab")), boost::const_formatter("c")); But wouldn't it be better to make a 'replace_if' shortcut solely for the purpose of documentation reasons: boost::replace_all_if(str, boost::is_any_of("ab"), "c"); I think that most people find the last line easier to read and comprehend than its (more powerful) 'find_format' cousin. The string_algo library is nice but I get lost more than once. Especially find, replace, erease with predicates are often used by us. However direct use seems not possible. wkr, me

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Passing extra compiler arguments with bjam
by Cory Nelson 01 Oct '07

01 Oct '07

I'm wanting to pass some extra arguments for VC++ whole program optimization (specifically, /GL to the compile, /LTCG to the linker). Does anyone know how? -- Cory Nelson

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Problem in calculating critical path and fundamental ckts
by abhishek.v＠tcs.com 01 Oct '07

01 Oct '07

Hi.. I want to calculate the critical paths of a graph using BGL. So what i did is i calculated the connected components of a graph then remove the edge one by one if the number of connected component increase then the edge is critical edge or a bridge. This works fine in case of undirected graph. But how do i calculate connected component of a directed or Bidirected graph i m able to calculate the strongly connected component but it is not helping me out. Can you suggest me something regarding this. Also i want to calculate the fundamental ckt that exist in a graph now. What i did here is i m calculating K-MST. Now i want to calculate the fundamental ckt how should i do that... Thanks Abhishek Vyas Tata Consultancy Services Mailto: abhishek.v(a)tcs.com Website: http://www.tcs.com ____________________________________________ Experience certainty. IT Services Business Solutions Outsourcing ____________________________________________ =====-----=====-----===== Notice: The information contained in this e-mail message and/or attachments to it may contain confidential or privileged information. If you are not the intended recipient, any dissemination, use, review, distribution, printing or copying of the information contained in this e-mail message and/or attachments to it are strictly prohibited. If you have received this communication in error, please notify us by reply e-mail or telephone and immediately and permanently delete the message and any attachments. Thank you

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Inquiring about the feasibility of boost::mpl based statechart DSELs that generate boost::statechart based components
by Tony Turner 01 Oct '07

01 Oct '07

Greetings; I am currently experimenting with the feasibility of writing a boost::mpl based library of metaprograms that process statechart DSEL language phrases ( see ref #1 below), that then specifically generate boost::statechart based components. I would be most grateful to hear from others regarding both difficulties to this approach, as well as success stories. If this approach seems feasible, I would like to contribute the resultant code back to the open source community. Since I'm not sure how the contribution process works, I would appreciate it if someone could point me in the right direction. Reference (#1) ( the statechart developed in chap 11, "A DSEL Design Walkthrough" in Abrahams and Gurtovoy's "C++ Template Metaprogramming book".) Thankyou very much for your time; Tony Turner R&D Software Engineer

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