Search Results

Search found 1973 results on 79 pages for 'boost spirit qi'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 23/79 | < Previous Page | 19 20 21 22 23 24 25 26 27 28 29 30  | Next Page >

  • Boost Mersenne Twister: how to seed with more than one value?

    - by Eamon Nerbonne
    I'm using the boost mt19937 implementation for a simulation. The simulation needs to be reproducible, and that means storing and potentially reusing the RNG seeds later. I'm using the windows crypto api to generate the seed values because I need an external source for the seeds and not because of any particular guarantees of randomness. The output of any simulation run will have a note including the RNG seed - so the seed needs to be reasonably short. On the other hand, as part of the analysis of the simulation, I'll be comparing several runs - but to be sure that these runs are actually different, I'll need to use different seeds - so the seed needs to be long enough to avoid accidental collisions. I've determined that 64-bits of seeding should suffice; the chance of a collision will reach 50% after about 2^32 runs - that probability is low enough that the average error caused by it is negligible to me. Using just 32-bits of seed is tricky; the chance of a collision reaches 50% already after 2^16 runs; and that's a little too likely for my tastes. Unfortunately, the boost implementation either seeds with a full state vector - which is far, far too long - or a single 32-bit unsigned long - which isn't ideal. How can I seed the generator with more than 32-bits but less than a full state vector? I tried just padding the vector or repeating the seeds to fill the state vector, but even a cursory glance at the results shows that that generates poor results.

    Read the article

  • Is there a Boost (or other common lib) type for matrices with string keys?

    - by mohawkjohn
    I have a dense matrix where the indices correspond to genes. While gene identifiers are often integers, they are not contiguous integers. They could be strings instead, too. I suppose I could use a boost sparse matrix of some sort with integer keys, and it wouldn't matter if they're contiguous. Or would this still occupy a great deal of space, particularly if some genes have identifiers that are nine digits? Further, I am concerned that sparse storage is not appropriate, since this is an all-by-all matrix (there will be a distance in each and every cell, provided the gene exists). I'm unlikely to need to perform any matrix operations (e.g., matrix multiplication). I will need to pull vectors out of the matrix (slices). It seems like the best type of matrix would be keyed by a Boost unordered_map (a hash map), or perhaps even simply an STL map. Am I looking at this the wrong way? Do I really need to roll my own? I thought I saw such a class somewhere before. Thanks!

    Read the article

  • Compiling my Boost/NTL program with c++ on Linux.

    - by Martin Lauridsen
    Hi SO, I wrote a client program and a server program, that uses the NTL library and Boost::Asio, to do client/server communication for an integer factorization application, in C++. Both sides consist of several headers and cpp files. Both project compile fine individually on Windows in Visual Studio. All I did, was add the include path of NTL and Boost to both projects: Additional include paths: "D:\Downloads\WinNTL-5_5_2\include";D:\boost_1_42_0 Furthermore, for both projects, I added the two library paths to both projects in VS: Additional library directories: D:\boost_1_42_0\stage\lib;"D:\Documents\Visual Studio 2008\Projects\ntl\Debug" And added under Additional dependencies: ntl.lib As said, it compiles fine on Windows. But when I put the code on a Linux machine provided by university, I try to compile with the following statement c++ -I/appl/htopopt/Linux_x86_64/NTL-5.4.2/include -I/appl/htopopt/Linux_x86_64/boost_1_43_0/include client_protocol.cpp mpqs_client.cpp mpqs_sieve.cpp mpqs_helper.cpp -o mpqs_helper -L/appl/htopopt/Linux_x86_64/NTL-5.4.2/lib -lntl -L/appl/htopopt/Linux_x86_64/gmp-4.2.1/lib -lgmp -lm -L/appl/htopopt/Linux_x86_64/boost_1_43_0/lib -lboost_system -static Upon doing this, I get a huuuge error, which I posted here. Any idea how to fix this, please??

    Read the article

  • (How) Can I approximate a "dynamic" index (key extractor) for Boost MultiIndex?

    - by Sarah
    I have a MultiIndex container of boost::shared_ptrs to members of class Host. These members contain private arrays bool infections[NUM_SEROTYPES] revealing Hosts' infection statuses with respect to each of 1,...,NUM_SEROTYPES serotypes. I want to be able to determine at any time in the simulation the number of people infected with a given serotype, but I'm not sure how: Ideally, Boost MultiIndex would allow me to sort, for example, by Host::isInfected( int s ), where s is the serotype of interest. From what I understand, MultiIndex key extractors aren't allowed to take arguments. An alternative would be to define an index for each serotype, but I don't see how to write the MultiIndex container typedef ... in such an extensible way. I will be changing the number of serotypes between simulations. (Do experienced programmers think this should be possible? I'll attempt it if so.) There are 2^(NUM_SEROTYPES) possible infection statuses. For small numbers of serotypes, I could use a single index based on this number (or a binary string) and come up with some mapping from this key to actual infection status. Counting is still darn slow. I could maintain a separate structure counting the total numbers of infecteds with each serotype. The synchrony is a bit of a pain, but the memory is fine. I would prefer a slicker option, since I would like to do further sorts on other host attributes (e.g., after counting the number infected with serotype s, count the number of those infected who are also in a particular household and have a particular age). Thanks in advance.

    Read the article

  • Dealing with selfish team member(s)

    - by thegreendroid
    My team is facing a difficult quandary, a couple of team members are essentially selfish (not to be confused with dominant!) and are cherry-picking stories/tasks that will give them the most recognition within the company (at sprint reviews etc. when all the stakeholders are present). These team members are very good at what they do and are fully aware of what they are doing. When we first started using agile about a year ago, I can say I was quite selfish too (coming from a very individual-focused past). I took ownership of certain stories and didn't involve anyone else in it, which in hindsight wasn't the right thing to do and I learnt from that experience almost immediately. We are a young team of very ambitious twenty somethings so I can understand the selfishness to some extent (after all everyone should be ambitious!). But the level to which this selfishness has reached of late has started to bother me and a few others within my team. The way I see it, agile/scrum is all about the team and not individuals. We should be looking out for each other and helping each other improve. I made this quite clear during our last retrospective, that we should be fair and give everyone a chance. I'll wait and see what comes out of it in the next few sprints. In the meantime, what are some of the troubles that you have faced with selfish members and how did you overcome them?

    Read the article

  • "Expected initializer before '<' token" in header file

    - by Sarah
    I'm pretty new to programming and am generally confused by header files and includes. I would like help with an immediate compile problem and would appreciate general suggestions about cleaner, safer, slicker ways to write my code. I'm currently repackaging a lot of code that used to be in main() into a Simulation class. I'm getting a compile error with the header file for this class. I'm compiling with gcc version 4.2.1. // Simulation.h #ifndef SIMULATION_H #define SIMULATION_H #include <cstdlib> #include <iostream> #include <cmath> #include <string> #include <fstream> #include <set> #include <boost/multi_index_container.hpp> #include <boost/multi_index/hashed_index.hpp> #include <boost/multi_index/member.hpp> #include <boost/multi_index/ordered_index.hpp> #include <boost/multi_index/mem_fun.hpp> #include <boost/multi_index/composite_key.hpp> #include <boost/shared_ptr.hpp> #include <boost/tuple/tuple_comparison.hpp> #include <boost/tuple/tuple_io.hpp> #include "Parameters.h" #include "Host.h" #include "rng.h" #include "Event.h" #include "Rdraws.h" typedef multi_index_container< // line 33 - first error boost::shared_ptr< Host >, indexed_by< hashed_unique< const_mem_fun<Host,int,&Host::getID> >, // 0 - ID index ordered_non_unique< tag<age>,const_mem_fun<Host,int,&Host::getAgeInY> >, // 1 - Age index hashed_non_unique< tag<household>,const_mem_fun<Host,int,&Host::getHousehold> >, // 2 - Household index ordered_non_unique< // 3 - Eligible by age & household tag<aeh>, composite_key< Host, const_mem_fun<Host,int,&Host::getAgeInY>, const_mem_fun<Host,bool,&Host::isEligible>, const_mem_fun<Host,int,&Host::getHousehold> > >, ordered_non_unique< // 4 - Eligible by household (all single adults) tag<eh>, composite_key< Host, const_mem_fun<Host,bool,&Host::isEligible>, const_mem_fun<Host,int,&Host::getHousehold> > >, ordered_non_unique< // 5 - Household & age tag<ah>, composite_key< Host, const_mem_fun<Host,int,&Host::getHousehold>, const_mem_fun<Host,int,&Host::getAgeInY> > > > // end indexed_by > HostContainer; typedef std::set<int> HHSet; class Simulation { public: Simulation( int sid ); ~Simulation(); // MEMBER FUNCTION PROTOTYPES void runDemSim( void ); void runEpidSim( void ); void ageHost( int id ); int calcPartnerAge( int a ); void executeEvent( Event & te ); void killHost( int id ); void pairHost( int id ); void partner2Hosts( int id1, int id2 ); void fledgeHost( int id ); void birthHost( int id ); void calcSI( void ); double beta_ij_h( int ai, int aj, int s ); double beta_ij_nh( int ai, int aj, int s ); private: // SIMULATION OBJECTS double t; double outputStrobe; int idCtr; int hholdCtr; int simID; RNG rgen; HostContainer allHosts; // shared_ptr to Hosts - line 102 - second error HHSet allHouseholds; int numInfecteds[ INIT_NUM_AGE_CATS ][ INIT_NUM_STYPES ]; EventPQ currentEvents; // STREAM MANAGEMENT void writeOutput(); void initOutput(); void closeOutput(); std::ofstream ageDistStream; std::ofstream ageDistTStream; std::ofstream hhDistStream; std::ofstream hhDistTStream; std::string ageDistFile; std::string ageDistTFile; std::string hhDistFile; std::string hhDistTFile; }; #endif I'm hoping the other files aren't so relevant to this problem. When I compile with g++ -g -o -c a.out -I /Applications/boost_1_42_0/ Host.cpp Simulation.cpp rng.cpp main.cpp Rdraws.cpp I get Simulation.h:33: error: expected initializer before '<' token Simulation.h:102: error: 'HostContainer' does not name a type and then a bunch of other errors related to not recognizing the HostContainer. It seems like I have all the right Boost #includes for the HostContainer to be understood. What else could be going wrong? I would appreciate immediate suggestions, troubleshooting tips, and other advice about my code. My plan is to create a "HostContainer.h" file that includes the typedef and structs that define its tags, similar to what I'm doing in "Event.h" for the EventPQ container. I'm assuming this is legal and good form.

    Read the article

  • Portable C++ library for IPC (processes and shared memory), Boost vs ACE vs Poco?

    - by user363778
    Hi, I need a portable C++ library for doing IPC. I used fork() and SysV shared memory until now but this limits me to Linux/Unix. I found out that there are 3 major C++ libraries that offer a portable solution (including Windows and Mac OS X). I really like Boost, and would like to use it but I need processes and it seems like that this is only an experimental branch until now!? I have never heard of ACE or POCO before and thus I am stuck I do not know which one to choose. I need fork(), sleep() (usleep() would be great) and shared memory of course. Performance and documentation are also important criteria. Thanks, for your Help!

    Read the article

  • Using boost.python to import a method with opencv calls but failing due to symbols not being found a

    - by nmz787
    So I don't have the code right now, as I am not home... but i used the boost library for python in C++ to allow python to access a function called something like loadImageIntoMainWindow(string filepath) in the C++ source code the method calls opencv methods that are imported at the top of the file, I included opencv in my Jamroot file, and also found a way to compile and link manually on the command line... in either case when I run my python file it complains that the symbols aren't found for the first function call to an opencv method... I will update as soon as I get home with the C++, the command line compilation lines, the Jamroot, and the python files

    Read the article

  • Parallel Programming. Boost's MPI, OpenMP, TBB, or something else?

    - by unknownthreat
    Hello, I am totally a novice in parallel programming, but I do know how to program C++. Now, I am looking around for parallel programming library. I just want to give it a try, just for fun, and right now, I found 3 APIs, but I am not sure which one should I stick with. Right now, I see Boost's MPI, OpenMP and TBB. For anyone who have experienced with any of these 3 API (or any other parallelism API), could you please tell me the difference between these? Are there any factor to consider, like AMD or Intel architecture?

    Read the article

  • Multi-Core Programming. Boost's MPI, OpenMP, TBB, or something else?

    - by unknownthreat
    Hello, I am totally a novice in Multi-Core Programming, but I do know how to program C++. Now, I am looking around for Multi-Core Programming library. I just want to give it a try, just for fun, and right now, I found 3 APIs, but I am not sure which one should I stick with. Right now, I see Boost's MPI, OpenMP and TBB. For anyone who have experienced with any of these 3 API (or any other API), could you please tell me the difference between these? Are there any factor to consider, like AMD or Intel architecture?

    Read the article

  • How to attach boost::shared_ptr (or another smart pointer) to reference counter of object's parent?

    - by Checkers
    I remember encountering this concept before, but can't find it in Google now. If I have an object of type A, which directly embeds an object of type B: class A { B b; }; How can I have a smart pointer to B, e. g. boost::shared_ptr<B>, but use reference count of A? Assume an instance of A itself is heap-allocated I can safely get its shared count using, say, enable_shared_from_this.

    Read the article

  • How do I know if a boost thread is done ?

    - by jules
    I am using boost::thread to process messages in a queue. When a first message comes I start a message processing thread. When a second message comes I check if the message processing thread is done. if it is done I start a new one if it is not done I don nothing. How do I know if the thread is done ? I tried with joinable() but it is not working, as when the thread is done, it is still joinable. I also tried to interrupt the process at once, and add an interruption point at the end of my thread, but it did not work. Thanks

    Read the article

  • How do I insert format str and don't remove the matched regular expression in input string in boost:

    - by Yadollah
    I want to put space between punctuations and other words in a sentence. But boost::regex_replace() replaces the punctuation with space, and I want to keep a punctuation in the sentence! for example in this code the output should be "Hello . hi , " regex e1("[.,]"); std::basic_string<char> str = "Hello.hi,"; std::basic_string<char> fmt = " "; cout<<regex_replace(str, e1, fmt)<<endl; Can you help me?

    Read the article

  • how to find all occurrences in REGEX with

    - by Vincenzo
    My code is: #include <boost/regex.hpp> boost::cmatch matches; boost::regex_match("alpha beta", matches, boost::regex("([a-z])+")); cout << "found: " matches.size() << endl; And it shows found: 2 which means that only ONE occurrence is found… How to instruct it to find THREE occurrences? Thanks!

    Read the article

  • Boost.MultiIndex: Are there way to share object between two processes?

    - by Arman
    Hello, I have a Boost.MultiIndex big array about 10Gb. In order to reduce the reading I thought there should be a way to keep the data in the memory and another client programs will be able to read and analyse it. What is the proper way to organize it? The array looks like: struct particleID { int ID;// real ID for particle from Gadget2 file "ID" block unsigned int IDf;// postition in the file particleID(int id,const unsigned int idf):ID(id),IDf(idf){} bool operator<(const particleID& p)const { return ID<p.ID;} unsigned int getByGID()const {return (ID&0x0FFF);}; }; struct ID{}; struct IDf{}; struct IDg{}; typedef multi_index_container< particleID, indexed_by< ordered_unique< tag<IDf>, BOOST_MULTI_INDEX_MEMBER(particleID,unsigned int,IDf)>, ordered_non_unique< tag<ID>,BOOST_MULTI_INDEX_MEMBER(particleID,int,ID)>, ordered_non_unique< tag<IDg>,BOOST_MULTI_INDEX_CONST_MEM_FUN(particleID,unsigned int,getByGID)> > > particlesID_set; Any ideas are welcome. kind regards Arman.

    Read the article

  • Why there is no scoped locks for multiple mutexes in C++0x or Boost.Thread?

    - by Vicente Botet Escriba
    C++0x thread library or Boost.thread define non-member variadic template function that lock all lock avoiding dead lock. template <class L1, class L2, class... L3> void lock(L1&, L2&, L3&...); While this function avoid help to deadlock, the standard do not includes the associated scoped lock to write exception safe code. { std::lock(l1,l2); // do some thing // unlock li l2 exception safe } That means that we need to use other mechanism as try-catch block to make exception safe code or define our own scoped lock on multiple mutexes ourselves or even do that { std::lock(l1,l2); std::unique_lock lk1(l1, std::adopted); std::unique_lock lk2(l2, std::adopted); // do some thing // unlock li l2 on destruction of lk1 lk2 } Why the standard doesn't includes a scoped lock on multiple mutexes of the same type, as for example { std::array_unique_lock<std::mutex> lk(l1,l2); // do some thing // unlock l1 l2 on destruction of lk } or tuples of mutexes { std::tuple_unique_lock<std::mutex, std::recursive_mutex> lk(l1,l2); // do some thing // unlock l1 l2 on destruction of lk } Is there something wrong on the design?

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 19 20 21 22 23 24 25 26 27 28 29 30  | Next Page >