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date formatting problem
by Sergey Skorokhodov 01 Dec '08

01 Dec '08

Hi, I'm trying to read dates in "%d%m%Y" (DDMMYYYY). Unfortunately, it doesn't work. Here is the code: #include <string> #include <stdexcept> #include <iostream> #include "boost/date_time/gregorian/gregorian.hpp" using std::string; using namespace boost::gregorian; using boost::date_time::not_a_date_time; using std::cout; using std::cin; using std::endl; using std::locale; int main() { try { date dt( not_a_date_time ); date_facet* facet(new date_facet("%d%m%Y")); cout.imbue( locale( cout.getloc(), facet ) ); cin.imbue( locale( cin.getloc(), facet ) ); cout.exceptions( std::ios_base::failbit ); cin.exceptions( std::ios_base::failbit ); cin >> dt; cout << dt << endl; } catch ( const std::exception& e ) { cout << typeid(e).name() << " " << e.what(); } return 0; } Here program output: > 18111957 > struct boost::gregorian::bad_month Month number is out of range 1..12 If date is assigned programmaticaly, then cout does work as expected and the date output is in %d%m%Y format. I've tried boost 1.33.1 and 1.36 What's wrong with my code? TIA

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About boost.mpi and boost 1.35
by Sofia Aparicio Secanellas 01 Dec '08

01 Dec '08

Hello! I want to install boost.mpi on my ubuntu. Using the synaptic I have installed boost 1.35, boost-build and bjam to follow the instructions of http://www.boost.org/doc/libs/1_37_0/doc/html/mpi/getting_started.html#mpi.… They say that I should run "bjam --with-mpi" in the top-level boost directory, but it is not clear for me where is this directory. I try to run this command in every directory where it was something about boost but it didnot work. /usr/include /usr/share/boost-build /usr/share/boost-build/tools The error message that I obtain is: error: no Jamfile in current directory found I have tried to do the same in another computer and in this case I have installed manually boost 1.37 and here it is working. Do you know what is the problem? boost 1.35 supports boost.mpi? Do I need to download boost manually? Thank you very much. Sofia Aparicio No virus found in this outgoing message Checked by PC Tools AntiVirus (4.0.0.26 - 10.100.007). http://www.pctools.com/free-antivirus/

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[Review] UUID library (mini-)review ends today, November 30rd
by Hartmut Kaiser 01 Dec '08

01 Dec '08

Hi all, the review of Andy Tompkins' UUID library ends today, November 30th. Nevertheless, it's still possible to submit a review for at least a week, as I'm not going to have time for the analysis of the review before Christmas. Thanks to all of you who submitted a review. Regards Hartmut Review Manager

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[PROTO] Custom functions, scalar terminal and make_expr vs details::as_expr_if
by Joel Falcou 30 Nov '08

30 Nov '08

I have a large number of custom unary and bin ary function that I map using unary_expr and binary_expr. The problem is the following : my grammar has integral or floating point scalar terminal. So, when I want to create a binary function that takes any elements of my domain, I'm boudn to do the following : template<class L,class R> typename result_of::make_expr<....>::type my_custom_binary_func( L const& l, R const& r ) { return make_expr( ... ); } Alas, as I already discussed with Eric, nothign prevent me to use my_custom_binary_func over types that aren't in my grammar. To do so, I was told to use SFINAE to prune unwanted element by matching the result type of make_expr on my grammar. However, this proves cumbersome and slow down compile time by *a large factor* when I have a large number of such function (and I have like 50 or 60). So i wandered into proto source code and looked at how proto solves this problem for its binary operator. This solution seems more elegant but as it live sin proto::detail, I don't think I'm intended to use it. So, how can I have a simple and fast creation of custom expression ? Am I missing something blatant ? -- ___________________________________________ Joel Falcou - Assistant Professor PARALL Team - LRI - Universite Paris Sud XI Tel : (+33)1 69 15 66 35

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Review Wizard Report for November 2008
by Ronald Garcia 30 Nov '08

30 Nov '08

============================================== Review Wizard Status Report for November 2008 ============================================== News ==== May 7 - Scope Exit Library Accepted - Awaiting SVN May 17 - Egg Library Rejected August 14 - Boost 1.36 Released New Libraries: Accumulators, Exception, Units, Unordered Containers August 27 - Finite State Machines Rejected September 10 - Data Flow Signals Rejected September 30 - Phoenix Accepted Conditionally November 3 - Boost 1.37 Released New Library: Proto November 10 - Thread-Safe Signals Accepted - Awaiting SVN November 25 - Globally Unique Identifier Library mini-Review in progress Older Issues ============ The Quantitative Units library, accepted in April 2007 is in SVN (listed as units). The Time Series Library, accepted in August 2007, has not yet been submitted to SVN. The Switch Library, accepted provisionally in January 2008, has not yet been submitted for mini-review and full acceptance. Property Map (Fast-Track) and Graph (Fast-Track) have been removed from the review queue. The author (Andrew Sutton) intends to submit a new version of this work at a later time. A few libraries have been reviewed and accepted into boost, but have not yet appeared in SVN as far as I can tell. Could some light be shed on the status of the following libraries? Apologies if I have simply overlooked any of them: * Flyweight (Joaquin Ma Lopez Munoz) * Floating Point Utilities (Johan Rade) * Factory (Tobias Schwinger) * Forward (Tobias Schwinger) * Scope Exit (Alexander Nasonov) * Time Series (Eric Niebler) * Property Tree (Marcin Kalicinski) -- No documentation in SVN Any information on the whereabouts of these libraries would be greatly appreciated. For libraries that are still waiting to get into SVN, please get them ready and into the repository. The developers did some great work making the libraries, so don't miss the chance to share that work with others. Also notice that the review process page has been updated with a section on rights and responsibilities of library submitters. General Announcements ===================== As always, we need experienced review managers. The review queue has been growing substantially but we have had few volunteers, so manage reviews if possible and if not please make sure to watch the review schedule and participate. Please take a look at the list of libraries in need of managers and check out their descriptions. In general review managers are active boost participants or library contributors. If you can serve as review manager for any of them, email Ron Garcia or John Phillips, "garcia at osl dot iu dot edu" and "phillips at mps dot ohio-state dot edu" respectively. We are also suffering from a lack of reviewers. While we all understand time pressures and the need to complete paying work, the strength of Boost is based on the detailed and informed reviews submitted by you. A recent effort is trying to secure at least five people who promise to submit reviews as a precondition to starting the review period. Consider volunteering for this and even taking the time to create the review as early as possible. No rule says you can only work on a review during the review period. A link to this report will be posted to www.boost.org. If you would like us to make any modifications or additions to this report before we do that, please email Ron or John. If you're a library author and plan on submitting a library for review in the next 3-6 months, send Ron or John a short description of your library and we'll add it to the Libraries Under Construction below. We know that there are many libraries that are near completion, but we have hard time keeping track all of them. Please keep us informed about your progress. Review Queue ============ * Lexer * Boost.Range (Update) * Shifted Pointer * Logging * Futures - Williams * Futures - Gaskill * Join * Pimpl * Constrained Value * Thread Pool * Polynomial -------------------- Lexer ----- :Author: Ben Hanson :Review Manager: Eric Neibler :Download: `Boost Sandbox Vault <http://boost-consulting.com/vault/ index.php? action=downloadfile&filename=boost.lexer.zip&directory=Strings%20-% 20Text%20Processing&>`__ :Description: A programmable lexical analyser generator inspired by 'flex'. Like flex, it is programmed by the use of regular expressions and outputs a state machine as a number of DFAs utilising equivalence classes for compression. Boost.Range (Update) -------------------- :Author: Neil Groves :Review Manager: Needed :Download: `Boost Sandbox Vault <http://www.boost-consulting.com/ vault/index.php?action=downloadfile&filename=range_ex.zip&directory=>`__ :Description: A significant update of the range library, including range adapters. Shifted Pointer --------------- :Author: Phil Bouchard :Review Manager: Needed :Download: `Boost Sandbox Vault <http://www.boost-consulting.com/ vault/index.php?&direction=0&order=&directory=Memory>`__ :Description: Smart pointers are in general optimized for a specific resource (memory usage, CPU cycles, user friendliness, ...) depending on what the user need to make the most of. The purpose of this smart pointer is mainly to allocate the reference counter (or owner) and the object itself at the same time so that dynamic memory management is simplified thus accelerated and cheaper on the memory map. Logging ------- :Author: John Torjo :Review Manager: Gennadiy Rozental :Download: http://torjo.com/log2/ :Description: Used properly, logging is a very powerful tool. Besides aiding debugging/testing, it can also show you how your application is used. The Boost Logging Library allows just for that, supporting a lot of scenarios, ranging from very simple (dumping all to one destination), to very complex (multiple logs, some enabled/some not, levels, etc). It features a very simple and flexible interface, efficient filtering of messages, thread-safety, formatters and destinations, easy manipulation of logs, finding the best logger/filter classes based on your application's needs, you can define your own macros and much more! Futures ------- :Author: Braddock Gaskill :Review Manager: Tom Brinkman :Download: http://braddock.com/~braddock/future/ :Description: Joint review of the Futures libraries scheduled for 1/5/09-1/20/09. The goal of the boost.future library is to provide a definitive future implementation with the best features of the numerous implementations, proposals, and academic papers floating around, in the hopes to avoid multiple incompatible future implementations in libraries of related concepts (coroutines, active objects, asio, etc). This library hopes to explore the combined implementation of the best future concepts. Futures ------- :Author: Anthony Williams :Review Manager: Tom Brinkman :Download: http://www.justsoftwaresolutions.co.uk/files/ n2561_future.hpp (code) http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/ n2561.html (description) :Description: Joint review of the Futures libraries scheduled for 1/5/09-1/20/09. This paper proposes a kind of return buffer that takes a value (or an exception) in one (sub-)thread and provides the value in another (controlling) thread. This buffer provides essentially two interfaces: * an interface to assign a value as class promise and * an interface to wait for, query and retrieve the value (or exception) from the buffer as classes unique_future and shared_future. While a unique_future provides move semantics where the value (or exception) can be retrieved only once, the shared_future provides copy semantics where the value can be retrieved arbitrarily often. A typical procedure for working with promises and futures looks like: * control thread creates a promise, * control thread gets associated future from promise, * control thread starts sub-thread, * sub-thread calls actual function and assigns the return value to the promise, * control thread waits for future to become ready, * control thread retrieves value from future. Also proposed is a packaged_task that wraps one callable object and provides another one that can be started in its own thread and assigns the return value (or exception) to a return buffer that can be accessed through one of the future classes. With a packaged_task a typical procedure looks like: * control thread creates a packaged_task with a callable object, * control thread gets associated future from packaged_task, * control thread starts sub-thread, which invokes the packaged_task, * packaged_task calls the callable function and assigns the return value, * control thread waits for future to become ready, * control thread retrieves value from future. Notice that we are in the unusual position of having two very different libraries with the same goal in the queue at the same time. The Review Wizards would appreciate a discussion of the best way to hold these two reviews to produce the best possible addition to Boost. Join ---- :Author: Yigong Liu :Review Manager: Needed :Download: http://channel.sourceforge.net/ :Description: Join is an asynchronous, message based C++ concurrency library based on join calculus. It is applicable both to multi-threaded applications and to the orchestration of asynchronous, event-based applications. It follows Comega's design and implementation and builds with Boost facilities. It provides a high level concurrency API with asynchronous methods, synchronous methods, and chords which are "join-patterns" defining the synchronization, asynchrony, and concurrency. Pimpl ----- :Author: Vladimir Batov :Review Manager: Needed :Download: `Boost Sandbox Vault <http://www.boost-consulting.com/ vault/index.php?action=downloadfile&filename=Pimpl.zip&directory=&>`__ http://www.ddj.com/cpp/205918714 (documentation) :Description: The Pimpl idiom is a simple yet robust technique to minimize coupling via the separation of interface and implementation and then implementation hiding. This library provides a convenient yet flexible and generic deployment technique for the Pimpl idiom. It's seemingly complete and broadly applicable, yet minimal, simple and pleasant to use. Constrained Value ----------------- :Author: Robert Kawulak :Review Manager: Jeff Garland :Download: http://rk.go.pl/f/constrained_value.zip :Description: Review scheduled for 12/1/08-12/10/08 The Boost Constrained Value library contains class templates useful for creating constrained objects. A simple example is an object representing an hour of a day, for which only integers from the range [0, 23] are valid values: :: bounded_int<int, 0, 23>::type hour; hour = 20; // OK hour = 26; // exception! Behavior in case of assignment of an invalid value can be customized. For instance, instead of throwing an exception as in the example above, the value may be adjusted to meet the constraint: :: wrapping_int<int, 0, 255>::type buffer_index; buffer_index = 257; // OK: wraps the value to fit in the range assert( buffer_index == 1 ); The library doesn't focus only on bounded objects as in the examples above -- virtually any constraint can be imposed by using a predicate: :: // constraint (a predicate) struct is_odd { bool operator () (int i) const { return (i % 2) != 0; } }; :: // and the usage is as simple as: constrained<int, is_odd> odd_int = 1; odd_int += 2; // OK ++odd_int; // exception! The library has a policy-based design to allow for flexibility in defining constraints and behavior in case of assignment of invalid values. Policies may be configured at compile-time for maximum efficiency or may be changeable at runtime if such dynamic functionality is needed. Thread Pool ----------- :Author: Oliver Kowalke :Review Manager: Needed :Download: `Boost Sandbox Vault <http://www.boostpro.com/vault/ index.php?action=downloadfile&filename=boost-threadpool. 2.tar.gz&directory=Concurrent%20Programming>`__ :Description: The library provides: - thread creation policies: determines the managemnt of worker threads - fixed set of threads in pool - create workerthreads on demand (depending on context) - let worker threads ime out after certain idle time - channel policies: manages access to queued tasks - bounded channel with high and low watermark for queuing tasks - unbounded channel with unlimited numer of queued tasks - rendezvous syncron hand-over between producer and consumer threads - queueing policy: determines how tasks will be removed from channel - FIFO - LIFO - priority queue (attribute assigned to task) - smart insertions and extractions (for instance remove oldest task with certain attribute by newst one) - tasks can be chained and lazy submit of taks is also supported (thanks to Braddocks future library). - returns a task object from the submit function. The task it self can be interrupted if its is cooperative (means it has some interruption points in its code -> ``this_thread::interruption_point()`` ). Polynomial ---------- :Author: Pawel Kieliszczyk :Review Manager: Needed :Download: `Boost Sandbox Vault <http://www.boostpro.com/vault/ index.php? action=downloadfile&filename=polynomial.zip&directory=>`__ :Description: The library was written to enable fast and faithful polynomial manupulation. It provides: - main arithmetic operators (+, -, * using FFT, /, %), - gcd, - different methods of evaluation (Horner Scheme, Compensated Horner Algorithm, by preconditioning), - derivatives and integrals, - interpolation, - conversions between various polynomial forms (special functions for creating Chebyshev, Hermite, Laguerre and Legendre form). Libraries under development =========================== Please let us know of any libraries you are currently developing that you intend to submit for review.

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Re: [Boost-users] Problem linking boost filesystem 1_36_0 on ubuntu gcc 4.2
by SkiltZ 30 Nov '08

30 Nov '08

Have you try using those g++ option: -lboost_filesystem ex: g++ -DHAVE_CONFIG_H -I. -I/home/.../Projects/myProject/src -I.. -O0 -g3 -lboost_program_options -lboost_filesystem -MT options.o -MD -MP -MF .deps/mysrc.Tpo -c -o options.o /home/.../Projects/myProject/src/mysrc.cpp With this option I could link my program ;) Best Regards. SkiltZ Kevin Stevens-4 wrote: > > Answering my own question. Hopefully someone can google this error in the > future and fix it a lot quicker than the several hours it took me.... > > The problem was that I was not correctly specifying the include headers. I > had entered -I/path/to/boost_1_36_0/boost not -I/path/to/boost_1_36_0. I > thought I had that path right because everything was compiling. What I did > not take into account was that boost 1_34_1 was installed via the package > manager by the administrator of the system so the include files were > automatically being picked up despite me not explicitly specifying them. > The interfaces I was using did not change, but the underlying code did, > hence my code still compiled, but refused to link and unfortunately spit > out misleading errors. > > > -K > > From: Kevin Stevens > Sent: Thursday, October 30, 2008 5:15 PM > To: 'boost-users(a)lists.boost.org' > Subject: Problem linking boost filesystem 1_36_0 on ubuntu gcc 4.2 > > Hello, when I am trying to link boost::filesystem into my program I am > receiving link errors. I am trying to convert from boost 1_34_1 to > 1_36_0- previously this built against 1_34_1 without any issue. > > > When I link I get the following error: > /home/kstevens/code/CrossingEngine/../lib/libtypes.a(Config_Constants.o): > In function > `boost::enable_if<boost::filesystem::is_basic_path<boost::filesystem::basic_path<std::basic_string<char, > std::char_traits<char>, std::allocator<char> >, > boost::filesystem::path_traits> >, bool>::type > boost::filesystem::exists<boost::filesystem::basic_path<std::basic_string<char, > std::char_traits<char>, std::allocator<char> >, > boost::filesystem::path_traits> > >(boost::filesystem::basic_path<std::basic_string<char, > std::char_traits<char>, std::allocator<char> >, > boost::filesystem::path_traits> const&)': > /usr/include/boost/filesystem/operations.hpp:279: undefined reference to > `boost::filesystem::detail::status_api(std::basic_string<char, > std::char_traits<char>, std::allocator<char> > const&, int&)' > > > I did an objdump -CT on libboost_filesystem-gcc42-mt-1_36.so and got the > following two functions as output but not the one the linker appears to be > looking for: > 000000000000c4e0 g DF .text 00000000000000e3 Base > boost::filesystem::detail::status_api(std::string const&, > boost::system::error_code&) > 000000000000c720 g DF .text 00000000000000e3 Base > boost::filesystem::detail::symlink_status_api(std::string const&, > boost::system::error_code&) > > > Could this be a bad build? Am I missing something- perhaps I need to link > another file in? I built 1_36_0 myself using a default configuration other > than telling it where to put the output libs. I have ensured that I am > linking against and including headers from 1_36_0, and have also made a > clean build. Is there anything else I should try? > > Thank you, > -Kevin > > > This is my code snippet that uses boost::filesystem: > > //Create Directory if it does not already exist. > if(!boost::filesystem::exists(reportFilePath)) > { > cout << "output path: " << reportFilePath << " did not exist, > which may indicate a different configuration than was intended, creating > directory now." << endl; > try > { > boost::filesystem::path path(reportFilePath); > boost::filesystem::create_directory(path); > } > catch(boost::filesystem::filesystem_error e) > { > cout << "Error: " << e.what() << endl; > } > > } > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > -- View this message in context: http://www.nabble.com/Problem-linking-boost-filesystem-1_36_0-on-ubuntu-gcc… Sent from the Boost - Users mailing list archive at Nabble.com.

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[boost::string_algo] Minor documentation error
by Anders Dalvander 29 Nov '08

29 Nov '08

Hi, I found a minor error in the Boost String Algorithms documentation for Boost 1.37. http://www.boost.org/doc/libs/1_37_0/doc/html/boost/algorithm/is_less.html Documentation states "Compare two operands using > operator", when implementation use < operator. http://www.boost.org/doc/libs/1_37_0/doc/html/boost/algorithm/is_not_greate… Documentation states "Compare two operands using > operator", when implementation use <= operator. Best regards, Anders Dalvander

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rule python-extension unknown in module Jamfile
by Patrick Meier 29 Nov '08

29 Nov '08

Hello, I am trying to get started with boost.python. When following the tutorial http://www.boost.org/doc/libs/1_37_0/libs/python/doc/tutorial/doc/html/pyth… I get the same problems that have been described in https://bugs.launchpad.net/ubuntu/+source/boost/+bug/164551, namely: $ bjam --toolset=gcc test Jamroot:18: in modules.load rule python-extension unknown in module Jamfile</usr/share/doc/libboost-doc/examples/libs/python/example>. /usr/share/boost-build/build/project.jam:312: in load-jamfile /usr/share/boost-build/build/project.jam:68: in load /usr/share/boost-build/build/project.jam:170: in project.find /usr/share/boost-build/build-system.jam:248: in load /usr/share/boost-build/kernel/modules.jam:261: in import /usr/share/boost-build/kernel/bootstrap.jam:132: in boost-build /usr/share/doc/libboost-doc/examples/libs/python/example/boost-build.jam:7: in module scope $ This may be an Ubuntu problem, but there was no reaction on the bug report since one year. Can you suggest a solution or explain how to find the cause of the problems? (I am running Ubuntu 8.10 and have installed the packages (among others) libboost-python-dev libboost-python1.34.1 boost-build libboost-doc bjam) Thank you Patrick

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Intersection Points in Higher Dimension
by Chaman Singh Verma 28 Nov '08

28 Nov '08

Hello, How can I know the intersection points of the polytope defined by a_1 x_1 + a_2 x_2 + ........................................ a_n x_n = b_1 . . . where n is very large number. Besides knowing the corner vertices of the polytope, I am interested in knowing the (n-2), (n-1) simplices. Please let me know if they can be done using CGAL. Thanks, csv Poona, India

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ignoring stuff
by jono 28 Nov '08

28 Nov '08

hi all, i'm trying to ignore unecognized lines of input (so following lines can be processed without the parse failing). eg: very simple scenario as follows: ///=================================================== { using namespace boost::spirit; typedef file_iterator<char> iterator_t; typedef scanner<iterator_t, scanner_policies_t> scanner_t; typedef rule<scanner_t> rule_t; int red=0, green=0, blue=0; rule_t option = (str_p("red") >> '=' >> int_p[assign(red)]) | (str_p("green") >> '=' >> int_p[assign(green)]) | (str_p("blue") >> '=' >> int_p[assign(blue)]) | ; iterator_t first(filename.c_str()); if (!first) return; iterator_t last = first.make_end(); parse(first, last, *option, space_p); } ///=================================================== wiw is a parser that will skip over the unrecognized line with input like this: ------------------ red = 255 kermit = green green = 128 blue = 128 ------------------ and correctly interpret the green and blue values.. i played around with eol_p as i want to skip whole lines of unrecognized content. i thought it would be easy, but i can't seem to get it right. can anybody do my job for me? cheers Jono

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