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

Using BGL for huge grid graphs
by Knut Krause 21 Jan '14

21 Jan '14

Hi, I'm planning on using the BGL on huge graphs the represent a grid where each vertex is a cell connected to it's 8 neighbours. I think something around 2,500,000,000 vertices would be a good number to approach but it would be great if it could handle (a lot) more later. If I got this graph I have to find the shortest path between two vertices. Does anyone here have experiences with graphs that large? Is this even worth a try on "normal" hardware? The edge weights would be stored in the vertices. So if you want to go from (a) to (b) you'd have to pay the cost stored in (b). The graph is not directed either. I read about BGLs CSR graph http://www.boost.org/doc/libs/1_55_0/libs/graph/doc/compressed_sparse_row.h… but since I honestly have no clue how to use BGL yet I thought I'd first hear your opinons. Regards Knut

2 3

Re: [Boost-users] Cannot compile with multiprecision :: eval_*()functions
by Anderson Lebowski 21 Jan '14

21 Jan '14

looks like I went to the wrong track. Yes, merely the pow function works. Thank you very much! On Mon, Jan 20, 2014 at 8:42 AM, John Maddock <john(a)johnmaddock.co.uk>wrote: > I am trying to use eval_pow() and eval_powm() >> > > Those are internal details, you shouldn't really be using them in user > code. > > > My code is like this and I am using Visual Studio 12: >> >> #include <boost/multiprecision/cpp_int.hpp> >> ... >> boost::multiprecision::cpp_int pow("1234567"); >> boost::multiprecision::cpp_int base(3); >> boost::multiprecision::cpp_int result = 0; >> >> boost::multiprecision::default_ops::eval_pow(result, base, pow); >> >> I cannot figure out what's going on wrong when I compile it, the error >> message is like the following, Can anyone shed some light please? >> > > The eval_* functions take *Backends* and not *numbers* as arguments. > > In any case there is (deliberately) no integer pow function which accepts > an arbitrary precision exponent value - even 2^INT_MAX would run the > machine out of memory in a trice. > > What's wrong with: > > result = pow(base, 1234567); > > and let the expression template code handle memory management? > > John. > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users >

1 0

Cannot compile with multiprecision :: eval_*() functions
by Anderson Lebowski 20 Jan '14

20 Jan '14

Hi folks, I am trying to use eval_pow() and eval_powm() My code is like this and I am using Visual Studio 12: #include <boost/multiprecision/cpp_int.hpp> ... boost::multiprecision::cpp_int pow("1234567"); boost::multiprecision::cpp_int base(3); boost::multiprecision::cpp_int result = 0; boost::multiprecision::default_ops::eval_pow(result, base, pow); I cannot figure out what's going on wrong when I compile it, the error message is like the following, Can anyone shed some light please? D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/number_base.hpp(146): error C2039: 'unsigned_types' : is not a member of 'boost::multiprecision::number<boost::multiprecision::backends::cpp_int_backend<0,0,signed_magnitude,unchecked,std::allocator<boost::multiprecision::limb_type>>,et_on>' 1> D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/number_base.hpp(191) : see reference to class template instantiation 'boost::multiprecision::detail::canonical_imp<Val,Backend,boost::mpl::int_<1>>' being compiled 1> with 1> [ 1> Val=unsigned char 1> , Backend=double_type 1> ] 1> D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/integer_ops.hpp(309) : see reference to class template instantiation 'boost::multiprecision::detail::canonical<unsigned char,double_type>' being compiled 1> KeyGen.cpp(152) : see reference to function template instantiation 'void boost::multiprecision::default_ops::eval_powm<boost::multiprecision::cpp_int,int>(Backend &,const Backend &,const Backend &,Integer)' being compiled 1> with 1> [ 1> Backend=boost::multiprecision::cpp_int 1> , Integer=int 1> ] 1>D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/number_base.hpp(146): error C2146: syntax error : missing ',' before identifier 'unsigned_types' 1>D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/number_base.hpp(146): error C2065: 'unsigned_types' : undeclared identifier 1>D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/number_base.hpp(148): error C2977: 'boost::mpl::find_if' : too many template arguments 1> D:\Develop\C++\boost_1_55_1\boost/mpl/find_if.hpp(33) : see declaration of 'boost::mpl::find_if' 1>D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/number_base.hpp(148): error C2955: 'boost::mpl::find_if' : use of class template requires template argument list 1> D:\Develop\C++\boost_1_55_1\boost/mpl/find_if.hpp(33) : see declaration of 'boost::mpl::find_if' 1>D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/number_base.hpp(136): error C2039: 'signed_types' : is not a member of 'boost::multiprecision::number<boost::multiprecision::backends::cpp_int_backend<0,0,signed_magnitude,unchecked,std::allocator<boost::multiprecision::limb_type>>,et_on>' 1> D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/number_base.hpp(191) : see reference to class template instantiation 'boost::multiprecision::detail::canonical_imp<Val,Backend,boost::mpl::int_<0>>' being compiled 1> with 1> [ 1> Val=int 1> , Backend=double_type 1> ] 1> D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/integer_ops.hpp(310) : see reference to class template instantiation 'boost::multiprecision::detail::canonical<Integer,double_type>' being compiled 1> with 1> [ 1> Integer=int 1> ] 1>D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/number_base.hpp(136): error C2146: syntax error : missing ',' before identifier 'signed_types' 1>D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/number_base.hpp(136): error C2065: 'signed_types' : undeclared identifier 1>D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/number_base.hpp(138): error C2977: 'boost::mpl::find_if' : too many template arguments 1> D:\Develop\C++\boost_1_55_1\boost/mpl/find_if.hpp(33) : see declaration of 'boost::mpl::find_if' 1>D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/number_base.hpp(138): error C2955: 'boost::mpl::find_if' : use of class template requires template argument list 1> D:\Develop\C++\boost_1_55_1\boost/mpl/find_if.hpp(33) : see declaration of 'boost::mpl::find_if' 1>D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/integer_ops.hpp(336): error C2780: 'enable_if<boost::multiprecision::backends::is_trivial_cpp_int<boost::multiprecision::backends::cpp_int_backend<MinBits,MaxBits,SignType,Checked,Allocator>>,void>::type boost::multiprecision::backends::eval_right_shift(boost::multiprecision::backends::cpp_int_backend<MinBits,MaxBits,SignType,Checked,Allocator> &,T)' : expects 2 arguments - 1 provided 1> D:\Develop\C++\boost_1_55_1\boost/multiprecision/cpp_int/bitwise.hpp(355) : see declaration of 'boost::multiprecision::backends::eval_right_shift' 1>D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/integer_ops.hpp(336): error C2780: 'enable_if_c<!boost::multiprecision::backends::is_trivial_cpp_int<boost::multiprecision::backends::cpp_int_backend<MinBits,MaxBits,SignType,Checked,Allocator>>::value,void>::type boost::multiprecision::backends::eval_right_shift(boost::multiprecision::backends::cpp_int_backend<MinBits,MaxBits,SignType,Checked,Allocator> &,boost::multiprecision::double_limb_type)' : expects 2 arguments - 1 provided 1> D:\Develop\C++\boost_1_55_1\boost/multiprecision/cpp_int/bitwise.hpp(298) : see declaration of 'boost::multiprecision::backends::eval_right_shift' 1>D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/integer_ops.hpp(336): error C2780: 'void boost::multiprecision::default_ops::eval_right_shift(T &,const T &,const V)' : expects 3 arguments - 1 provided 1> D:\Develop\C++\boost_1_55_1\boost/multiprecision/detail/default_ops.hpp(758) : see declaration of 'boost::multiprecision::default_ops::eval_right_shift' ------------------------------ Thanks, -Anderson Lebowski

2 1

Boost.Mock ?
by Mathieu Champlon 20 Jan '14

20 Jan '14

Hello, I initially sent the following message to the boost-dev mailing list, but I'm thinking this might reach more potential users here on boost-users. Would a library for mock objects be of interest ? The documentation can be found here : http://mat007.users.sourceforge.net/boost_mock/ An archive is also available for download there : http://sourceforge.net/projects/mat007.u/files/boost-mock.zip It's been converted from turtle (http://turtle.sourceforge.net/) which was mentioned on the mailing-lists a couple of times in the past. There is a catch in that it needs Boost.Test from the release branch and doesn't compile with the trunk. The changes are minimal though and I can provide a patch if anyone is interested. Is anyone already using the library who would like to see it in Boost ? Or is anyone using another mock object library who wants to give it a go ? Or even better has anyone tried it and decided to user another library who would like to comment on it ? I would be highly interested in any feedback ! Thank you, MAT.

6 9

how to sort boost composite container
by Uthpal Urubail 20 Jan '14

20 Jan '14

I am using below composite container. Finally I am looking to sort

1 0

Question for Boost.Threads and Boost.Test
by young 20 Jan '14

20 Jan '14

According to Boost document, Boost.Test can only be statically linked. Boost.Threads can only be dynamically linked. Then what boost_unit_test_framework-vc100-mt-1_53.lib for? Is it for dynamically linked dll? what libboost_thread-vc100-mt-1_53.lib for? Is it for static library? -- View this message in context: http://boost.2283326.n4.nabble.com/Question-for-Boost-Threads-and-Boost-Tes… Sent from the Boost - Users mailing list archive at Nabble.com.

4 6

[Test] Where to learn about boost::itest::mock_object?
by Mateusz Loskot 20 Jan '14

20 Jan '14

Hi, I'm looking for a simple mocking library to use together with Boost.Test. There is Turtle (aka Boost.Mock) and googlemock. During retrospection of the big thread on Boost.Test future [1], I found this curious post by Gennadiy [2] about mock_object. I had no idea such facility lives in Boost.Test and it looks it's been there for very long time. I can't find any documentation about mock_oboject, only a couple of examples. So, I have a few questions: Is the mock_object an internal feature or is it dedicated (and ready) to use by Boost.Test users? What are basic features of this mocking facility? How does it compare to Turtle or googlemock? [1] http://thread.gmane.org/gmane.comp.lib.boost.devel/234297 [2] http://thread.gmane.org/gmane.comp.lib.boost.devel/234297/focus=234621 [3] find /home/mloskot/dev/boost/_svn/trunk/libs/test -type f | xargs grep mock_object Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

4 4

[Geometry] Registering the Windows RECT structure
by Sean Farrow 19 Jan '14

19 Jan '14

Hi all, Does anybody know whether the Windows RECT structure is known to the boost geometry library. The RECT structure is declared as follows: typedef struct _RECT { LONG left; LONG top; LONG right; LONG bottom; } RECT, *PRECT; Members left The x-coordinate of the upper-left corner of the rectangle. top The y-coordinate of the upper-left corner of the rectangle. right The x-coordinate of the lower-right corner of the rectangle. bottom The y-coordinate of the lower-right corner of the rectangle. If there is no registration, is there an example that shows how to do this? Any help appreciated. Regards Sean.

3 2

[xpressive] Accessing named capture from another scope in the semantic action
by Roger 19 Jan '14

19 Jan '14

Hi! Is it possible access captured group from another scope in the semantic action? Can I write a lazy function somehow and access another scope? The following code results in ”bad_lexical_cast” exception, likely due to the named capture "Year" is an empty string in the "outer scope". const sregex yyyymmdd = (Year=_d>>_d>>_d>>_d) >> (Month= _d>>_d) >> (Day= _d>>_d); sregex rx = yyyymmdd [ tm_year(t) = as<int>(Year) - 1900 /*, … */ ] // bad lexical cast: source type value could not be interpreted as target >> hhmmss [ tm_hour(t) = as<int>(Hour) /*, …*/ ] ; In my case the regex has no recursion, no captured repeated groups, so I can't understand really why I got nested result set. Dumping the nested result tree indicates that the values are captured in another ”scope”. But this is in the match_result<> set, and I can't figure out if there is any equivalent set available inside the semantic action. 20140119190000 #rx day = hour = minute = month = second = year = 20140119 #yyyymmdd day = 19 hour = minute = month = 01 second = year = 2014 190000 #hhmmss day = hour = 19 minute = 00 month = second = 00 year = I’m asking mostly for educational reason. Thanks for any hints! perrog Code: mark_tag Year(1),Month(2),Day(3),Hour(4),Minute(5),Second(6), Micro(7); const sregex yyyymmdd = (Year=_d>>_d>>_d>>_d) >> (Month= _d>>_d) >> (Day= _d>>_d); const sregex hhmmss = (Hour=_d>>_d)>>(Minute=_d>>_d)>>(Second=_d>>_d); bool is_datetime(std::string const& input) { // …don’t need any semantic actions when validating… smatch ignore; sregex rx = yyyymmdd >> hhmmss; return regex_match(input, ignore, rx); } bool get_datetime(std::string const& input, struct tm *time) { local<struct tm*> t(time); function<int tm::*>::type tm_year = { &tm::tm_year }; function<int tm::*>::type tm_hour = { &tm::tm_hour }; // … sregex rx = yyyymmdd [ tm_year(t) = as<int>(Year) - 1900 /*, … */ ] // bad lexical cast: source type value could not be interpreted as target >> hhmmss [ tm_hour(t) = as<int>(Hour) /*, …*/ ] ; smatch ignore; return regex_match(input, ignore, rx); }

2 1

boost multiprecision & STL map
by tridiak＠ihug.co.nz 19 Jan '14

19 Jan '14

I have a boost/C++ error which I am having a difficult time figuring out. Compiler error : Call to member function '__construct_node' is ambiguous Where StellarID()==0) {return errInvalidID;} if (stellarObjects.find(obj->StellarID())!= stellarObjects.end()) { return errStellarObjectIDClash; } stellarObjects[obj->StellarID()]=obj;

2 1