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C++11 Algorithms Book
by Algocoders . 30 Jan '13

30 Jan '13

The book "C++11 Algorithms Volume 1 : Using and Extending C++11, Boost and Beyond <http://www.algocoders.com/>" is published. *Table of Contents: http://www.algocoders.com/sites/default/files/toc_c%2B%2B11algorithms_vol1.… *<http://www.algocoders.com/sites/default/files/toc_c%2B%2B11algorithms_vol1.…> *Sample Chapter: http://www.algocoders.com/sites/default/files/chapter1_c%2B%2B11algorithms_… *<http://www.algocoders.com/sites/default/files/chapter1_c%2B%2B11algorithms_…> **<http://www.algocoders.com/sites/default/files/toc_c%2B%2B11algorithms_vol1.…> @Amazon : www.amazon.com/11-Algorithms-Volume-Extending-Beyond/dp/1482083396/<http://www.amazon.com/11-Algorithms-Volume-Extending-Beyond/dp/1482083396/> @Pothi.com (Indian Edition) : http://pothi.com/pothi/book/chandra-shekhar-kumar-c11-algorithms-volume-1<http://pothi.com/pothi/book/chandra-shekhar-kumar-c11-algorithms-volume-1> ** *Description* This book is vital to understand *algorithms* newly introduced in *C++11*with the help of practical examples illustrating *concepts*, *variations*, *customizations* and *correctness* with deep insight into internals with primary focus on *effective usage*. This book can be read by anyone having some experience in any higher level programming. Beginners in C++ will be able to learn basic concepts of C++11 algorithms with practical examples. Intermediate programmers in C++ will learn foundational aspect of C++11 algorithms in a pragmatic way. Expert programmers(aka C++ hackers) can enjoy interesting variations leading to future of C++11 algorithms(aka C++1y), Boost and beyond. This book(*Volume 1*) illustrates following algorithms: - *Numeric Algorithms* - Simulating for-loop iteration with iota - Customizing iota - Return Type of iota - Compile Time iota - Interesting variations of iota - *Quantifier Algorithms* - Universal Quantifier(*Predicate Satisfiability For All*) - Non-Existential Quantifier(*Predicate Satisfiability For None*) - Existential Quantifier(*Predicate Satisfiability For Some*) - Unique Quantifier(*Predicate Satisfiability For One*) - *Partition Algorithms* - Predicate Based Rearrangements - Partition Structure Validation - Bisection Algorithm - Group Partitions *Recommended Approach* Though this book can be read without reference to any other source, still we recommend our readers to keep a copy of the famous book *The C++ Standard Library, Second Edition : A Tutorial and Reference by Nicolai M. Josuttis* handy for gentle introduction to C++11 algorithms followed by diving into respective sections of our book for detailed information. In-depth treatment of foundational aspect of C++11 algorithms is covered in another book published by us Foundation of Algorithms in C++11, Volume 1(Revised Edition) : Using and Extending C++11, Boost and Beyond.<http://www.amazon.com/Foundation-Algorithms-Volume-Revised-Edition/dp/14819…> For more details, please visit the link : http://www.algocoders.com/article/books Enjoy Reading ! Cheers, Algocoders http://www.algocoders.com paranoids(a)algocoders.com

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[Fusion] Associative Sequence not so associative
by TONGARI 30 Jan '13

30 Jan '13

Hi, I'd expect the associative sequence could be constructed and assigned with another sequence in different order. But it doesn't work, the src sequence must in the same order as the dst sequence defined. E.g. map<pair<K1, int>, pair<K2, int> > cannot take make_map<K2, K1>(1, 2). This is a bit disappointing :-( Does I miss something?

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[Range][Iterator] iterate over an enumeration?
by John M. Dlugosz 29 Jan '13

29 Jan '13

I'd like to make it easy to do a BOOST_FOREACH for every value in an enumeration. I tried enum E { E_First, ⋯ , E_Last }; boost::counting_range(E_First, E_Last) but got compiler template barf. Can someone suggest a good way to do this?

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serialization
by Larry E. Ramey 29 Jan '13

29 Jan '13

I'm having some trouble with the portable_binary_archive. When we serialze our classes via the text archive, they go in and out just fine. My simple test cases work great with the portable_binary_archive. However, in our production code, I get an input stream error exception tossed when I try to read a class that has STL elements in it. I have tried reordering includes and making sure the boost/serialization/list.hpp or whatever comes in front of the STL list class. Heck, I even put all those includes as the very 1st line of my test program to make sure they were included 1st. I am at a loss as the exception really doesn't tell me much, and the only thing I could figure out is that reordering the includes did in fact fix a few of these exceptions. (I still have one left... very annoying) Any ideas? I'd post the code, but it is very intertwined and difficult to distill a clean example. (and my stupid trail test does in fact work) Larry

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regular expression to extract numbers
by Neil Sutton 29 Jan '13

29 Jan '13

Hi, I am new to using boost and am trying to learn basics so I can use regex features in my code. In my test program, I want a function to simply extract some numbers that follow after a certain string pattern and then to read those numbers into a vector. This is an outline of what i would like to do: // function definition #ifndef findnumbers.h #define findnumbers.h #include <string> #include <fstream> #include <vector> #include <boost/regex.hpp> #endif void findnumbers (ifstream& afile) { // assume file is opened in main - i have passed a reference boost::regex expression ( ....having trouble with this); // search for matches - there will be a fixed number of numbers e.g 10 std::string const_iterator start, end; start = afile.begin( ); end = afile.end( ); std::vector<int> results; boost::match_results<std::vector<int>::const_iterator> what; for(int count = 0; count !=10; count++) { boost::regex_search(start,end,what,expression) { //if a number is found place in the vector results.push_back(count); } So the first problem I have is defining a correct expression. The pattern has the format "sometext>NUMBERS<sometext" newline. The NUMBERS may be one or two digits combined and the pattern is repeated 10 times. I have searched the archives and tried to build something based on the examples I have read, but cannot seem to find a working solution. Can anyone help please in defining an expression? I do not need a solution to my function overall as I should be able to write it correctly once I know how to define the pattern. Kind regards

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[GIL] Why does 'get_color' take a tag object instead of its type only?
by TONGARI 29 Jan '13

29 Jan '13

Hi there, I'm curious of why gil::get_color(pixel, tag) is defined that way. Any need to take the tag value? If not, I'd prefer gil::get_color<Tag>(pixel) or just gil::get<Tag>(pixel) or even Tag::get(pixel). And if possible, I hope GIL would just make pixel a Fusion sequence. Thanks.

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stack_allocator
by Andrew Hundt 29 Jan '13

29 Jan '13

Is there some version of a stack allocator in the current 1.52 version of boost, perhaps in some detail namespace? I searched the source and the archives and the only one I could find disappeared after 1.39: http://www.boost.org/doc/libs/1_39_0/boost/signals2/detail/stack_allocator.… Cheers! Andrew Hundt

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Which Parallel Boost Graph Library should I use?
by Christopher Cowing-Zitron 29 Jan '13

29 Jan '13

Hello, There is more than one PBGL server, one hosted by Boost, and the other by the Open Systems Laboratory (OSL). It appears that each has code not included in the other, whether I look at the release or sandbox SVN versions of the library. I have three criteria as to which version(s) I should use, which are all equally important to my final choice. First, in general, which is more reliable, the Boost or the OSL version? Both Boost and the OSL know their stuff, so it's not that I question the authors' skill, but rather I don't know which version has received more testing and validation. Second, which is more up-to-date, both in terms of which is updated more frequently, and which is more algorithmically and mathematically current? While I know programmers do love their graph algorithms, I wonder if the actual computer scientists and mathematicians at the OSL are more on the cutting edge. Finally, whether I use the Boost or the OSL server, I am more interested in the sandbox version than the release, as the development version has a lot of good stuff which isn't present in the release. That being said, in my experience there is quite a bit of variability amongst sandbox libraries as to their readiness for use, and I am not sure whether either PBGL sandbox is functional. Note, if there is some feature in one of the sandboxes that I am quite interested in, but is not yet at production quality, I wouldn't mind fixing it up for the community. Answers to any or all of the above questions would be most appreciated. Have a good day, -- Chris

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narrowing conversion warning in boost's regex_traits_defaults.hpp when trying to initialize wregex object
by rsk82 29 Jan '13

29 Jan '13

The first line compiles ok. The second also produces working EXE, but in addition I get this large error: In file included from d:\boost/boost/regex/v4/regex_traits.hpp:35:0, from d:\boost/boost/regex/regex_traits.hpp:27, from d:\boost/boost/regex/v4/regex.hpp:39, from d:\boost/boost/regex.hpp:31, from test.cpp:4: d:\boost/boost/regex/v4/regex_traits_defaults.hpp: In instantiation of 'const charT* boost::re_detail::get_escape_R_string() [with charT = wchar_t]': d:\boost/boost/regex/v4/basic_regex_parser.hpp:804:54: required from 'bool boost::re_detail::basic_regex_parser<charT, traits>::parse_extended_escape() [with charT = wchar_t; traits = boost::regex_traits<wchar_t>]' d:\boost/boost/regex/v4/basic_regex_parser.hpp:308:36: required from 'bool boost::re_detail::basic_regex_parser<charT, traits>::parse_extended() [with charT = wchar_t; traits = boost::regex_traits<wchar_t>]' d:\boost/boost/regex/v4/basic_regex_parser.hpp:134:10: required from 'void boost::re_detail::basic_regex_parser<charT, traits>::parse(const charT*, const charT*, unsigned int) [with charT = wchar_t; traits = boost::regex_traits<wchar_t>]' d:\boost/boost/regex/v4/basic_regex.hpp:215:7: required from 'void boost::re_detail::basic_regex_implementation<charT, traits>::assign(const charT*, const charT*, boost::re_detail::basic_regex_implementation<charT, traits>::flag_type) [with charT = wchar_t; traits = boost::regex_traits<wchar_t>; boost::re_detail::basic_regex_implementation<charT, traits>::flag_type = unsigned int]' d:\boost/boost/regex/v4/basic_regex.hpp:661:4: required from 'boost::basic_regex<charT, traits>& boost::basic_regex<charT, traits>::do_assign(const charT*, const charT*, boost::basic_regex<charT, traits>::flag_type) [with charT = wchar_t; traits = boost::regex_traits<wchar_t>; boost::basic_regex<charT, traits>::flag_type = unsigned int]' d:\boost/boost/regex/v4/basic_regex.hpp:382:33: required from 'boost::basic_regex<charT, traits>& boost::basic_regex<charT, traits>::assign(const charT*, const charT*, boost::basic_regex<charT, traits>::flag_type) [with charT = wchar_t; traits = boost::regex_traits<wchar_t>; boost::basic_regex<charT, traits> = boost::basic_regex<wchar_t, boost::regex_traits<wchar_t> >; boost::basic_regex<charT, traits>::flag_type = unsigned int]' d:\boost/boost/regex/v4/basic_regex.hpp:367:48: required from 'boost::basic_regex<charT, traits>& boost::basic_regex<charT, traits>::assign(const charT*, boost::basic_regex<charT, traits>::flag_type) [with charT = wchar_t; traits = boost::regex_traits<wchar_t>; boost::basic_regex<charT, traits> = boost::basic_regex<wchar_t, boost::regex_traits<wchar_t> >; boost::basic_regex<charT, traits>::flag_type = unsigned int]' d:\boost/boost/regex/v4/basic_regex.hpp:336:7: required from 'boost::basic_regex<charT, traits>::basic_regex(const charT*, boost::basic_regex<charT, traits>::flag_type) [with charT = wchar_t; traits = boost::regex_traits<wchar_t>; boost::basic_regex<charT, traits>::flag_type = unsigned int]' test.cpp:15:37: required from here d:\boost/boost/regex/v4/regex_traits_defaults.hpp:329:73: warning: narrowing conversion of ''\37777777605'' from 'char' to 'const wchar_t' inside { } [-Wnarrowing] d:\boost/boost/regex/v4/regex_traits_defaults.hpp:331:64: warning: narrowing conversion of ''\37777777605'' from 'char' to 'const wchar_t' inside { } [-Wnarrowing] code : #include <iostream> #include <boost/regex.hpp> int main() { boost::regex narrow_str_regex("a+"); boost::wregex wide_str_regex(L"a+"); } boost: http://sourceforge.net/projects/boost/files/boost/1.52.0/boost_1_52_0.7z compiler: http://sourceforge.net/projects/mingwbuilds/files/host-windows/releases/4.7… ( and I know that this is the bug: https://svn.boost.org/trac/boost/ticket/7263 ) so, any tricks to get around this (some compiler switches?, I dunno) ? Or can I just ignore this error ? (Yes I need regex matching on wide strings.) -- View this message in context: http://boost.2283326.n4.nabble.com/narrowing-conversion-warning-in-boost-s-… Sent from the Boost - Users mailing list archive at Nabble.com.

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[1.53.0] Beta release candidates 2 now available for testing
by Marshall Clow 28 Jan '13

28 Jan '13

Updated release candidate files for 1.53.0 beta 1 are available at http://boost.cowic.de/rc/ As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. This helps ensure the candidates build OK before we push them out to SourceForge. The files (and associated md5s) are: 579b680bf55f53cd6d50adc391cb6c23 *boost_1_53_0_beta1_rc2.tar.gz 02098bb6da0e9c10712ae63c16e6aeea *boost_1_53_0_beta1_rc2.tar.bz2 998e2616a66c50e5693f563afb899002 *boost_1_53_0_beta1_rc2.zip e4fde6a869a3e21f8751ba8b7fd471a8 *boost_1_53_0_beta1_rc2.7z There were three changes between rc1 and rc2: * Fixes for compilation errors in Boost.Serialization * Documentation updates for Boost.SmartPtr * Updates to Boost.Threads Thanks, --The release managers

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