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ublas - newbie question and comment
by Mike Hayford 07 Jan '03

07 Jan '03

I discovered uBLAS a week ago and am very impressed by the design and implementation of the library. To learn the library I have been porting a few non-linear least squares codes from FORTRAN into uBLAS. A real hinderance is the documentation. There is no user's guide or set of example code to orient the new user to uBLAS. Some of the most valuable features are undocumented - such as scalar_vector, vector_indirect, and matrix_indirect. The widespread adoption of uBLAS by the C++ numeric community would be more rapid if these omissions were addressed. I would be willing to write up some of the *simple* examples I have done, if people think it would be useful. If my implementations can be improved, that would be even better. I'm new to Boost and haven't yet completely RTFM'd the requirements for Boost doc contributions so point me in the right direction if I'm going astray here. Having said that, I have a specific problem I'm trying to solve. I'm looking for the best "uBLAS-style" solution - I can do an element-by-element brute force solution. Problem: write the product of a diagonal matrix and a vector when the diagonal matrix is stored as a vector. So what I want to do figuratively is: int n = 5; vector<double> x(n), y(n), diag(n); diagonal_matrix<double> dMat(n); dMat = diag; x = prod(dMat, y); Is there a matrix adaptor of some sort that can fill the role of diagonal_matrix<> above? I looked in the header files and didn't see anything obvious. Thanks in adavance for your help. Mike Hayford --------------------------------- Do you Yahoo!? Yahoo! Mail Plus - Powerful. Affordable. Sign up now [Non-text portions of this message have been removed]

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[date_time] error C2782: _STL::abs() : template parameter 'T' is ambiguous
by Nick Toze <geeky_nick＠yahoo.co.uk> 06 Jan '03

06 Jan '03

Hello, Seems a bit similar to an earlier post, but this is using msvc6. The ambiguity is with "stlport\stl\_complex.h" (version 4.5.3). The error is: d:\c_plus_plus\boost_1_29_0\boost\date_time\compiler_config.hpp(33) : error C2782: ' __cdecl _STL::abs()' : template parameter 'T' is ambiguous could be 'long double' or 'const struct _STL::complex<long double> &' d:\c_plus_plus\boost_1_29_0\boost\date_time\compiler_config.hpp(33) : error C2785: ' __cdecl _STL::abs()' and 'long double __cdecl _STL::abs(const struct _STL::complex<long double> &)' have different return types d:\c_plus_plus\boost_1_29_0\boost\date_time\compiler_config.hpp(30) : see declaration of 'abs' d:\c_plus_plus\boost_1_29_0\boost\date_time\compiler_config.hpp(33) : error C2782: ' __cdecl _STL::abs()' : template parameter 'T' is ambiguous could be 'double' or 'const struct _STL::complex<double> &' d:\c_plus_plus\boost_1_29_0\boost\date_time\compiler_config.hpp(33) : error C2785: ' __cdecl _STL::abs()' and 'double __cdecl _STL::abs(const struct _STL::complex<double> &)' have different return types d:\c_plus_plus\boost_1_29_0\boost\date_time\compiler_config.hpp(30) : see declaration of 'abs' d:\c_plus_plus\boost_1_29_0\boost\date_time\compiler_config.hpp(33) : error C2782: ' __cdecl _STL::abs()' : template parameter 'T' is ambiguous could be 'float' or 'const struct _STL::complex<float> &' d:\c_plus_plus\boost_1_29_0\boost\date_time\compiler_config.hpp(33) : error C2785: ' __cdecl _STL::abs()' and 'float __cdecl _STL::abs(const struct _STL::complex<float> &)' have different return types d:\c_plus_plus\boost_1_29_0\boost\date_time\compiler_config.hpp(30) : see declaration of 'abs'

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error C2668: 'abs' : ambiguous call to overloaded function
by Black Ice 06 Jan '03

06 Jan '03

boost version 2002-01-02 VC 7.1 Final Beta "error C2668: 'abs' : ambiguous call to overloaded function" when compile following code. The same code can be built successfully in vc6. Any suggestion are appreciated. #define DATE_TIME_INLINE #define BOOST_DATE_TIME_POSIX_TIME_STD_CONFIG #include <iostream> #include <string> using namespace std; #include <boost/date_time/gregorian/gregorian.hpp> #include <boost/date_time/posix_time/posix_time.hpp> using namespace boost::gregorian; using namespace boost::posix_time; void testDateTime2() { date d(2002, Nov, 1); //an arbitrary date ptime t1(d, hours(5) + nanosec(100));//date + time of day offset ptime t2 = t1 - minutes(4)+seconds(2); ptime now = second_clock::local_time(); //use the clock //Get the date part out of the time date today = now.date(); date tommorrow = today + date_duration(1); ptime tommorrow_start(tommorrow); //midnight cout << "d is " << to_iso_extended_string(d) << endl; cout << "t1 is " << to_iso_extended_string(t1) << endl; cout << "t2 is " << to_iso_extended_string(t2) << endl; cout << "now is " << to_iso_extended_string(now) << endl; cout << "today is " << to_iso_extended_string(today) << endl; cout << "tommorrow is " << to_iso_extended_string(tommorrow) << endl; cout << "tommorrow_start is " << to_iso_extended_string(tommorrow_start) << endl; //starting at current time iterator adds by one hour time_iterator titr(now,hours(1)); for (; titr < tommorrow_start; ++titr) { cout << to_iso_extended_string(*titr) << endl; } } -- /*******************/ ×ÔÓÉ£šliberty£©ÎÞ·ÇŸÍÊÇÕâÑùÒ»ÖÖ³ÐÅµ£ºÃ¿žöÈËœ«»áµÃµœÒ»ÖÖ±£ÕÏ£¬±£ÕÏÎÒÃÇ¿ÉÒÔÓë ÈšÍþ¡¢¶àÊý¡¢Á÷Ë×Œ°ÓßÂÛµÄÓ°ÏìÏà¿¹ºâ¡£ /*******************/

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RE: [Boost-Users] Re: error C2668: 'abs' : ambiguous call to overloaded function
by Jeff Garland 06 Jan '03

06 Jan '03

> After I move the line 'using std namespace', the error still occurs. > The error occurs in file date_time/time_duration.hpp, line 66. > min_type minutes() const > { > return std::abs(((ticks() / (60*rep_type::res_adjust())) % 60)); > } > It seems like the abs function declared in boost/date_time/compiler_config. hpp will not be included due to the macro configuration. The relavant code snippet is: //boost/date_time/compiler_config.hpp //Work around compilers that don't have std::abs #if (__GNUC__ <= 3)|| (defined(BOOST_MSVC) && _MSC_VER <= 1200) # define BOOST_NO_LONG_LONG_ABS #endif #if defined(BOOST_NO_LONG_LONG_ABS) namespace std { template <typename T> // JDG [7/6/02 made a template] inline T abs(T x) { return x < 0 ? -x : x; } } #endif You might try altering this so that the function will be defined. Something like (line 22) #if (__GNUC__ <= 3)|| defined(BOOST_MSVC) should do the trick. The only thing is that past testing with newer versions of MSVC did not require this so I'm a bit suprised that this is needed. This will only work if the problem is that the compiler is trying to convert the underlying type boost::int64_t into a long or another type because it lacks a std::abs for this type. Jeff

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Re: [Boost-Users] Re: error C2668: 'abs' : ambiguous call to overloade
by martynl＠cix.compulink.co.uk 06 Jan '03

06 Jan '03

In-Reply-To: <av5tpc$fmj$1(a)main.gmane.org> Black Ice, > After I move the line 'using std namespace', the error still occurs. > The error occurs in file date_time/time_duration.hpp, line 66. > min_type minutes() const > { > return std::abs(((ticks() / (60*rep_type::res_adjust())) % 60)); > } For VC++ 7.1, we've enabled by default conformant overloads of abs that were previously disabled by default. As a result, you'll need to cast the result of your math to a specific type to ensure you get the abs you want. Martyn Lovell Software Architect Visual C++ Team - Libraries email: lnytram(a)tfosorcim.moc [Spam-avoidance: reverse each word in the email address before use] This posting is provided "AS IS" with no warranties, and confers no rights.

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Compile error when build boost with vc 7 and vc 7.1
by Black Ice 04 Jan '03

04 Jan '03

The last version of boost has got by CVS. set BOOST_ROOT=d:\boost\boost set VC7_ROOT=D:\Program Files\Microsoft Visual Studio .NET 2003\Vc7 bjam "-sTOOLS=vc7" Command line error D2016 : '/Za' and '/Ze' command-line options are incompatible -- /*******************/ ×ÔÓÉ£šliberty£©ÎÞ·ÇŸÍÊÇÕâÑùÒ»ÖÖ³ÐÅµ£ºÃ¿žöÈËœ«»áµÃµœÒ»ÖÖ±£ÕÏ£¬±£ÕÏÎÒÃÇ¿ÉÒÔÓë ÈšÍþ¡¢¶àÊý¡¢Á÷Ë×Œ°ÓßÂÛµÄÓ°ÏìÏà¿¹ºâ¡£ /*******************/

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auto_array?
by Duane Murphy 04 Jan '03

04 Jan '03

Is there a class filling in the missing piece to the memory management puzzle for an auto_array? We have: scoped_ptr and scoped_array, shared_ptr and shared_arry, and auto_ptr. I would like to have an auto_array. Basically the feature that is missing is to create an array, initialize it and then transfer ownership as a way of managing exceptions during the initialization phase. For the time being I am using a shared_array. Thank for any suggestions. ...Duane

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Re: [Boost-Users] Re: Re: Re: Slight Alteration to Boost Directory Structure
by William E. Kempf 04 Jan '03

04 Jan '03

> From: "Paul Mensonides" <yg-boost-users(a)m.gmane.org> > "William E. Kempf" <wekempf(a)cox.net> wrote in message > news:20030108174453.YIAW22825.lakemtao04.cox.net@smtp.east.cox.net... > > > > That is not what he (or I) means. He is suggesting that the path to > > > "shared_ptr.hpp" should be "$INCLUDE/boost/shared_ptr.hpp" rather than > > > "$INCLUDE/boost/boost/shared_ptr.hpp", which is the way it is now. > > > Everything would still be the same for including headers except that > only a > > > single search path is necessary to setup with the compiler. > > > > That's the way it is now *only* if you set your include directories > incorrectly. When they are properly set to $BOOST_ROOT then it's only > <boost/shared_ptr.hpp>, not <boost/boost/shared_ptr.hpp>. > > ...which is precisely the point. You have to have a separate include > directory for Boost, rather than a single directory which contains various > libraries. I.e. it would be nice to have a directory structure like this: > > $INCLUDE/ > Loki/*.* > Boost/*.* > > And then have only a single header directory: $INCLUDE. I'm not talking > about the paths in the source code (i.e. <boost/shared_ptr.hpp>); I'm > talking about the include directories that the compiler searches, which is > external to the source code. That still misses the point. Boost currently won't help you to install the library, but installation certainly wouldn't entail copying the entire $BOOST_ROOT tree to the $INCLUDE directory on your system. You'd only copy the $BOOST_ROOT/boost tree there. William E. Kempf wekempf(a)cox.net

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RegEx: (?= ) and (?! )
by Yutaka Emura <yutaka＠emurasoft.com> 02 Jan '03

02 Jan '03

Hi, I am using RegEx in Boost v1.29.0. (?= ) and (?! ) expressions do not seem to work at a certain condition. In the following example, "(?=a)b" should match "b" in "xyzabcdefg", but does not. Similarly, "(?!a)b" should not match "b" in "xyzabcdefg" but it does. Can please let me know what is wrong? Thank you for your reply in advance. Yutaka Emura --------- boost::regex expression; boost::match_results<std::string::const_iterator> subexp; expression.assign("(?=a)b", boost::regbase::perl); if (boost::regex_search((std::string::const_iterator)"xyzabcdefg", (std::string::const_iterator)"xyzabcdefg" + 10, subexp, expression, boost::match_default)) { { // should go here } else { // goes here } expression.assign("(!=a)b", boost::regbase::perl); if (boost::regex_search((std::string::const_iterator)"xyzabcdefg", (std::string::const_iterator)"xyzabcdefg" + 10, subexp, expression, boost::match_default)) { { // goes here } else { // should go here }

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concept check warnings
by s_j_turner <s_j_turner＠yahoo.co.uk> 02 Jan '03

02 Jan '03

FWIW, I just started looking at Jeremy Siek's concept checking tools, and my compiler(*) came up with a warning about name hiding which is trivial to fix. I was using ContainerConcept, and it uses a method argument with the same name as a data member. The fix looks like: *** concept_check.hpp Fri Dec 27 16:51:51 2002 --- concept_check.hpp Thu Jan 2 16:13:03 2003 *************** *** 708,719 **** function_requires< AssignableConcept<Container> >(); const_constraints(c); } ! void const_constraints(const Container& c) { ! i = c.begin(); ! i = c.end(); ! n = c.size(); ! n = c.max_size(); ! b = c.empty(); } Container c; bool b; --- 708,719 ---- function_requires< AssignableConcept<Container> >(); const_constraints(c); } ! void const_constraints(const Container& cc) { ! i = cc.begin(); ! i = cc.end(); ! n = cc.size(); ! n = cc.max_size(); ! b = cc.empty(); } Container c; bool b; There are a few other classes in there which do the same thing, but this is the only one I'm currently using. --- (*) Sun Forte 6.2.1

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RE: [Boost-Users] Re: Simple boost program throws exception
by Tom Matelich 02 Jan '03

02 Jan '03

I don't have too much advice except a) try the latest boost b) put a try/catch block around the code, figure out what function is calling and what exception is being thrown. > -----Original Message----- > From: ksaleh2 <ksaleh2(a)yahoo.com> [mailto:ksaleh2@yahoo.com] > Sent: Wednesday, January 01, 2003 9:21 AM > To: Boost-Users(a)yahoogroups.com > Subject: [Boost-Users] Re: Simple boost program throws exception > > > Hi, > > On December 7th I've posted this message, which unfortunately didn't > get any reply. I'm not a professional programmer, so forgive me if it > is a silly question, but your cooperation will help me understand > boost better, thank you and happy new year to all. > > --- In Boost-Users(a)yahoogroups.com, "ksaleh2 <ksaleh2@y...>" > <ksaleh2@y...> wrote: > > I'm trying boost for the first time on Codewarrior 8.0 for windows. > > The Boost version is 1.25.1 from the "Boost Graph Library" > > accompanying CD. The offensive code is : > > > > #include <boost/config.hpp> > > #include <iostream> > > > > #include <boost/graph/adjacency_list.hpp> > > > > using namespace boost; > > using namespace std; > > > > > > int main() > > { > > typedef adjacency_list<vecS,vecS,directedS, > > property < vertex_name_t, char > >,property<edge_weight_t,double> > > > Graph; > > > > property_map < Graph, vertex_name_t >::type name_map ; > > property_map < Graph, edge_weight_t >::type value_map ; > > > > Graph g; > > > > typename graph_traits<Graph>::vertex_descriptor a,b; > > > > a = add_vertex(g); name_map[a] = 'a'; > > b = add_vertex(g); name_map[b] = 'b'; > > > > typename graph_traits<Graph>::edge_descriptor ed; > > bool inserted; > > > > tie(ed, inserted) = add_edge(a, b, g); > > value_map[ed] = 1.2; > > > > > > return 0; > > } > > > > > > If the second template parameter for class VertexListS is replaced > > with listS it compiles and run normally. > > > > typedef adjacency_list<vecS,listS,directedS, > > property < vertex_name_t, char > >,property<edge_weight_t,double> > > > Graph; > > > > Can you please advise why? > > > > Best Regards > > > > ------------------------ Yahoo! Groups Sponsor > ---------------------~--> > Flexible Keyboard is the ideal accessory for PDA users that > are on the move. > http://us.click.yahoo.com/dCBVZC/WnCFAA/xGHJAA/EbFolB/TM > -------------------------------------------------------------- > -------~-> > > Info: <http://www.boost.org> > Wiki: <http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl> > Unsubscribe: <mailto:boost-users-unsubscribe@yahoogroups.com> > > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ ----------------------------------------------------------------------- DISCLAIMER: Information contained in this message and/or attachment(s) may contain confidential information of Zetec, Inc. If you have received this transmission in error, please notify the sender by return email. -----------------------------------------------------------------------

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Error in testing tuple
by agiatojon <JonAgiato＠nyc.rr.com> 01 Jan '03

01 Jan '03

Happy Holidays to everyone! I am getting aquainted with the tuple class but am encountering the following error: c:\BGL\boost_1_29_0\boost\tuple\tuple_comparison.hpp(119): error C2027: use of undefined type 'boost::STATIC_ASSERTION_FAILURE<x>' with [ x=false ] with the following program: /** * tupleTest.cpp * Test of Boost library class tuple * A tuple is a fixed size collection of elements * Stored objects may be of different types * Current support of tuples with 0-10 objects * Objects may be any valid C++ type except void and function types * Jon Agiato * 12-23-02 */ #include <iostream> using std::cout; using std::cin; using std::ostream; using std::cerr; #include <cstdlib> #include <boost/tuple/tuple.hpp> using boost::tuple; // both tuple_io.hpp and tuple_comparison.hpp include tuple.hpp // tuple_io must be included for tuple input and output operators #include <boost/tuple/tuple_io.hpp> // tuple_comparison.hpp must be included for comparison operators #include <boost/tuple/tuple_comparison.hpp> #include <string> using std::string; #include <exception> using std::exception; class A { friend ostream &operator<<(ostream &output, const A &a) { output << a.S; return output; } public: A(string s = "Testing"):S(s) {;} string S; }; class B { friend ostream &operator<<(ostream &output, const B &b) { output << b.D; return output; } public: B(double d = 3.501):D(d) {;} double D; }; class C { friend ostream &operator<<(ostream &output, const C &c) { output << c.state; return output; } public: C(bool st = true):state(st) {;} double state; }; int main() { try { tuple<A, B, C> testTuple; cout << testTuple << '\n'; tuple<B, A> test2Tuple; if(testTuple == test2Tuple) cout << testTuple << " is equal to " << test2Tuple << '\n'; else cout << testTuple << " is not equal to " << test2Tuple << '\n'; cout << "Press enter to exit..."; cin.get(); return EXIT_SUCCESS; } catch(const exception &E) { cerr << "Standard library exception: " << E.what() << '\n'; return EXIT_FAILURE; } catch(...) { cerr << "Unknown exception thrown.\n"; return EXIT_FAILURE; } } I am using Visual Studio.NET Enterprise Architect Thanks! Jon Agiato JonAgiato(a)nyc.rr.com

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Simple boost program throws exception
by ksaleh2 <ksaleh2＠yahoo.com> 01 Jan '03

01 Jan '03

I'm trying boost for the first time on Codewarrior 8.0 for windows. The Boost version is 1.25.1 from the "Boost Graph Library" accompanying CD. The offensive code is : #include <boost/config.hpp> #include <iostream> #include <boost/graph/adjacency_list.hpp> using namespace boost; using namespace std; int main() { typedef adjacency_list<vecS,vecS,directedS, property < vertex_name_t, char >,property<edge_weight_t,double> > Graph; property_map < Graph, vertex_name_t >::type name_map ; property_map < Graph, edge_weight_t >::type value_map ; Graph g; typename graph_traits<Graph>::vertex_descriptor a,b; a = add_vertex(g); name_map[a] = 'a'; b = add_vertex(g); name_map[b] = 'b'; typename graph_traits<Graph>::edge_descriptor ed; bool inserted; tie(ed, inserted) = add_edge(a, b, g); value_map[ed] = 1.2; return 0; } If the second template parameter for class VertexListS is replaced with listS it compiles and run normally. typedef adjacency_list<vecS,listS,directedS, property < vertex_name_t, char >,property<edge_weight_t,double> > Graph; Can you please advise why? Best Regards

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Success stories
by Miki_Tebeka＠amat.com 01 Jan '03

01 Jan '03

Hello All, I'm trying to convince my boss to use boost. Any helpful success stories/big users/anything that can help? 10x. Bye. ----------------------------------------------------------------------------- Smile, damn it, smile. lambda msg: { 'name' : 'Miki Tebeka', 'email' : 'miki_tebeka(a)amat.com', 'url' : 'http://www.cs.bgu.ac.il/~tebeka', 'quote' : 'The only difference between children and adults is the price of the toys' }[msg]

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shared_ptr and VC++ .net
by mwong <cmwong＠cedara.com> 30 Dec '02

30 Dec '02

Hi, I was trying to compile the following code using VC++ .NET. #include "stdafx.h" #include "boost/smart_ptr.hpp" int _tmain(int argc, _TCHAR* argv[]) { boost::shared_ptr<int> spc = new int(0); return 0; } I got the following error messages: c:\boost\smart_ptr.hpp(375) : error C2065: 'T' : undeclared identifier c:\boost\smart_ptr.hpp(375) : error C2687: cannot define a nested UDT of a template class out of line c:\boost\smart_ptr.hpp(375) : fatal error C1903: unable to recover from previous error(s); stopping compilation The offending code in smart_ptr.hpp is: template<typename T> struct less< boost::shared_ptr<T > > //..... LINE 375 : binary_function<boost::shared_ptr<T>, boost::shared_ptr<T>, bool> { bool operator()(const boost::shared_ptr<T>& a, const boost::shared_ptr<T>& b) const { return less<T*>()(a.get(),b.get()); } }; Can someone please tell me what is the problem? I was able to compile the same code using VC++ 6.0. Thanks. Ming

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RE: [Boost-Users] Re: boost::date_time : iterator model
by Jeff Garland 30 Dec '02

30 Dec '02

Dave A wrote: > Jeff, I remember discussing this with you at Oopsla last year -- why > not use the iterator adaptors library to help you build correct > iterators? Bad excuses only. The first date iterators pre-dated iterator adaptors. When I sat down to convert things over it was 'less-than easy'. I read the docs and experimented, but couldn't get things working -- this might have been related to 2.9x series of compilers I was using at the time, but no matter. When I ran out of patience I just dropped it and never got back to it. It has been on my 'todo' list ever since... Jeff

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RE: [Boost-Users] mpl::for_each
by Aleksey Gurtovoy 30 Dec '02

30 Dec '02

Oleg Grunin wrote: > It would be useful IMHO if mpl::for_each took its functor argument by > reference or better yet, became aware of boost::reference_wrapper. Done, the latter, check out the CVS. Thanks for the suggestion! Aleksey

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Error when I tried to compile an example
by g9news02 <g9news02＠yahoo.com.au> 30 Dec '02

30 Dec '02

Hi all, I tried to compile an example provided with the Boost date time library but kept getting the following error message: "/pssource/current/thirdparty/boost/boost_1_29_0/boost/type_traits/is_void.hpp", line 23: Warning: Too few arguments in macro BOOST_PP_CHECK_2. "/pssource/current/thirdparty/boost/boost_1_29_0/boost/type_traits/is_void.hpp", line 23: Error: BOOST_PP_LIST_FOR_EACH_I_M is not defined. "/pssource/current/thirdparty/boost/boost_1_29_0/boost/type_traits/is_void.hpp", line 23: Error: Use ";" to terminate declarations. "/pssource/current/thirdparty/boost/boost_1_29_0/boost/type_traits/is_void.hpp", line 23: Error: Use ";" to terminate declarations. "/pssource/current/thirdparty/boost/boost_1_29_0/boost/type_traits/is_void.hpp", line 26: Warning: Too few arguments in macro BOOST_PP_CHECK_2. "/pssource/current/thirdparty/boost/boost_1_29_0/boost/type_traits/is_void.hpp", line 26: Warning: Too few arguments in macro BOOST_PP_CHECK_2. "/pssource/current/thirdparty/boost/boost_1_29_0/boost/type_traits/is_void.hpp", line 26: Warning: Too few arguments in macro BOOST_PP_CHECK_2. "/pssource/current/thirdparty/boost/boost_1_29_0/boost/type_traits/is_void.hpp", line 26: Error: BOOST_PP_LIST_FOR_EACH_I_M is not defined. "/pssource/current/thirdparty/boost/boost_1_29_0/boost/type_traits/is_void.hpp", line 26: Error: Use ";" to terminate declarations. "/pssource/current/thirdparty/boost/boost_1_29_0/boost/type_traits/is_void.hpp", line 26: Error: Use ";" to terminate declarations. "/pssource/current/thirdparty/boost/boost_1_29_0/boost/type_traits/is_void.hpp", line 27: Warning: Too few arguments in macro BOOST_PP_CHECK_2. Does anyone know how to fix the problem. Thanks in advance.

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type_traits/is_convertible crashes Forte 6.2u2 and Forte 7.0
by Robert A. Reece 29 Dec '02

29 Dec '02

I put the following line in a file (it's the only line...) #include <boost/type_traits/is_convertible.hpp> And compiled as such: CC -I$BOOST temp.cpp Under both Forte 6.2u2 (running under Solaris 8) and Forte 7.0 (solaris 9), it produces the following: /hades02/pega/pegdevlcl/work> CC -I$PEGDEV3RD/boost/1.29.0 temp.cpp >> Assertion: (../links/init.cc, line 957) while processing /tsgnt1/pegdevsrc/3rd/src/boost/1.29.0/boost/type_traits/is_convertible.hpp at line 118. Has anybody else seen this? I checked the latest CVS archive and didn't see any updates to this file. The odd thing is that line 118 is blank. Thanks -Rob

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mpl::for_each
by Oleg Grunin 29 Dec '02

29 Dec '02

It would be useful IMHO if mpl::for_each took its functor argument by reference or better yet, became aware of boost::reference_wrapper.

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mpl begin end
by Oleg Grunin 29 Dec '02

29 Dec '02

Since mpl algorithms unlike their stl counterparts take sequences not iterators how does one run them on a subset of a container.

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boost::date_time : iterator model
by klapshin <klapshin＠yahoo.com> 29 Dec '02

29 Dec '02

Hello, I am an a process of adapting our codebase to boost date_time library, and one quite annoying problem I encountered is that date iterators conform to InputIterator model, rather then Random Access Iterator. By the nature of application I have to calculate quite often something like current date plus N months. The only way I see so far is doing something like date d(2002,Dec,26); month_iterator mi(d); for( size_t i=0; i < 5; ++i) ++mi; d = *mi; This is rather awkward, not to mention inefficient. I was trying to search both User and Developers mailing lists for "date InputIterator" hoping to find out what was the reason to use InputIterators, but no luck. BTW, how am I supposed to roll few months back? It is a forward iterator not even a bidirectional. Even more critique: the iterator is not exactly InputIterator, since it has only prefix increment, and no postfix one. Best regards, Kirill Lapshin.

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RE: [Boost-Users] Re: boost::date_time : iterator model
by Jeff Garland 28 Dec '02

28 Dec '02

>However I will try to give it a shot. What is the right >place to take latest source code from? Regular Boost CVS >repository on SourceForge? Yes, the boost CVS repository on sourceforge has the latest source. Jeff

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Property maps / Graph library
by rradh <rradh＠yahoo.com> 25 Dec '02

25 Dec '02

Hi, The examples in libs/graph/example have property_map like vertex_name that associates a 'vertex -> user-defined name' (usually a std::string). Without having to use an external std::map, is there any way to create a property_map that provides the reverse association 'user-defined name -> vertex', so that I can retreive the vertex based on the user-defined name and without iterating thru each vertex. Thanks Rajesh

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[BGL] Simplest way to implement bool isReachable(Vertex src, Vert ex target, Graph g) was: [Boost-Users] Re: Extended use of BGL File Depen dency Example
by Tom Matelich 24 Dec '02

24 Dec '02

> From: Tom Matelich [mailto:tmatelich@zetec.com] > > From: Tom Matelich [mailto:tmatelich@zetec.com] > > From: David Abrahams [mailto:dave@boost-consulting.com] > > > Tom Matelich <tmatelich(a)zetec.com> writes: > > > > From: David Abrahams [mailto:dave@boost-consulting.com] > > > >> Tom Matelich <tmatelich(a)zetec.com> writes: > > > >> > > > >> > trying to make my graphviz representation look nicer and I > > > >> was wondering if > > > >> > there is an algorithm already for simplifying: > > > > > > > > -----B\ > > > > A--< \ > > > > --------C > > > > D----------/ > > > > > > > > to: > > > > > > > > A---B---C > > > > D------/ > > > > > > > > This eliminated the A-C edge. <snip discussion of minimum spanning tree. It won't work because I require all reachability to be maintained. > so here's my psuedo-algorithm: for each vertex V for each out-edge E for each out-edge E_prime (double loop) if(isReachable(target(E_prime), target(E)) remove_edge(E) In other words if one of V's children can reach the target vertex of a given edge, then that edge can be removed. If someone could let me know how to implement bool isReachable(Vertex src, Vertex target, Graph g); I would really appreciate it. Or if you have a better algorithm, I'd love to hear it. Thanks, Tom ----------------------------------------------------------------------- DISCLAIMER: Information contained in this message and/or attachment(s) may contain confidential information of Zetec, Inc. If you have received this transmission in error, please notify the sender by return email. -----------------------------------------------------------------------

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