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Boost.Generic sources?
by Nathan Ridge 05 Mar '12

05 Mar '12

I just read about the Boost.Generic library at https://github.com/boostcon/2011_presentations/raw/master/thu/Boost.Generic…. It looks amazing! I understand it's not fully complete, but are the sources available somewhere? Thanks, Nate.

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Problem building boost MPI with Visual Studio 2010
by k m 05 Mar '12

05 Mar '12

Hi All I have installed openmpi in C:\Program Files\OpenMPI_v1.5.4-win32\ in an XP box and want to compile boost to produce graph-parallel library. But got the following error: The system cannot find the path specified. The system cannot find the path specified. The system cannot find the path specified. The system cannot find the path specified. MPI auto-detection failed: unknown wrapper compiler C:/Program Files/OpenMPI_v1. 5.4-win32/bin/mpic++.exe Please report this error to the Boost mailing list: http://www.boost.org You will need to manually configure MPI support. MPI launcher: mpirun -np when I ran in a Visual Studio 2010 command prompt: b2 --toolset=msvc-10.0 --build-type=complete architecture=x86 address-model=32 stage --debug-configuration I added the MPI config in boost_1_48_0\tools\build\v2\user-config.jam as below: using mpi : "C:/Program Files/OpenMPI_v1.5.4-win32/bin/mpic++.exe" ; Could anyone help on this? Gary

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Boost msm
by keithzz 05 Mar '12

05 Mar '12

newbi question pleasee bare with me as Im struggling with this. I want to use boost msm state machine but i am having a hard time imagining how it works. Let say we only have 2 states (s1, s2) and to go from s1 to s2 you need event e1 to be fired and to bo back you need another one e2. e1 and e2 can only be fired from within s1 and s2 respectively. Now in main() I start by starting the statemachine (start()) then ill have a while loop that every 1 min will go back to the state machine but have to pick up from where it left.i.e. main() { MSM.start(); //start state machine while (a_condition) { ProcessInputsfromIO(); Go_backtoStatemachine(); //how can i do this? delay(1min) } MSM.stop(); } So basically when a state finishes executing, the statemachine will exit, then ill have a delay of 1 minutes, then the while loop will need to take me back to the state I was before I exit, or I think that's how we should implement a state machine. Is what I am asking for out of the ordinary? If yes then how do people implement a non-blocking state machine? if no, then how can I implement Go_backtoStatemachine()? -- View this message in context: http://boost.2283326.n4.nabble.com/Boost-msm-tp4444830p4444830.html Sent from the Boost - Users mailing list archive at Nabble.com.

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regex: link issue on Visual Studio 11 (v17) x64
by Oleg Smolsky 05 Mar '12

05 Mar '12

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Problem with thread
by Jothybasu Selvaraj 05 Mar '12

05 Mar '12

---------- Forwarded message ---------- From: Jothybasu Selvaraj <jothybasu(a)gmail.com> Date: Mon, Mar 5, 2012 at 10:08 AM Subject: Problem with thread To: boost-users(a)lists.boost.org Hi all, I am new to boost libs, I ma trying to use the threading capabilities of boost. I am using QtCreator. While building Ithe compiler always throw an "Instantiated from here" error. The error is from shared_mutex.hpp on line state_data const current_state=interlocked_compare_exchange(&state,new_state ,old_state); What could be the problem? Thanks -- Jothy -- Jothy

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Clang error with GIL: make_step_iterator invisible to locator.hpp
by Tom Vercauteren 05 Mar '12

05 Mar '12

Hi all, I am trying to compile with clang (svn version) a project that uses Boost GIL (1.49) (among other things). Currently it fails to compile and issues the following message: boost/gil/locator.hpp:267:14: error: call to function 'make_step_iterator' that is neither visible in the template definition nor found by argument-dependent lookup Loking at the code of locator.hpp, I indeed see the call to make_step_iterator but no include of step_iterator.hpp where make_step_iterator is defined. Replacing #include "pixel_iterator.hpp" by #include "step_iterator.hpp" at line 28 of locator.hpp seems to fix my issue with clang. What's a bit strange to me is that the same code compiles fine with gcc 4.5. Am I hitting a GIL bug, a clang bug or am I wrongly calling GIL? I haven't written a small self-contained test code yet but will try to do so in case the answer to my question isn't obvious. Best, Tom

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Graph Structural Information
by Nouf M. 05 Mar '12

05 Mar '12

Hello, I have two very huge graphs, I need to select one to work with. Both graphs have one node type and one edge type. Both also have the same semantic meaning. Therefore, my choice should depend on some structural characteristics (e.g. degree distribution)... I so that BGL can provide me with the degree distribution in a manual way... I have two questions: Is there some specific functions that I can call to give me all structural characteristics of a graph? If not, what do you recommend I should look for other than the degree distribution to make up my choice? I cannot make a random choice... Best regards, Nouf

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C++ committee calling for lib proposals
by Noe Casas Manzanares 05 Mar '12

05 Mar '12

The C++ committee is calling for library proposals for their inclusion in C++11: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3370.html . I think some of the boost libraries are good candidates, like the recently accepted boost::lockfree. Has anyone considered sending such proposal?

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Re: [Boost-users] Boost-users Digest, Vol 3016, Issue 2
by Andrew Maclean 04 Mar '12

04 Mar '12

> > ---------- Forwarded message ---------- > From: Barend Gehrels <barend(a)xs4all.nl> > To: boost-users(a)lists.boost.org > Cc: > Date: Sun, 04 Mar 2012 18:01:52 +0100 > Subject: Re: [Boost-users] [Geometry] Calculating distances on the earth > Hi Sean, > > On 4-3-2012 17:14, Sean Farrow wrote: > > Hi all:**** > > I need to calculate distances on the earth. Ideally I’d like to use the > haversine formula.**** > > There is an example in the docs at:**** > > > http://www.boost.org/doc/libs/1_49_0/libs/geometry/doc/html/geometry/quicks… > **** > > under the non-Cartesian heading.**** > > Will this do what I need, or do I need the Geographical coordinate system, > (if yes where is this available and what features does this supply?)**** > > > This will do what you ask for. So it will calculate distances on the Earth > using the Haversine formula. > > However, it considers the Earth as a perfect sphere, which it is not. So > distances are rough approximations. > > If you need more precise results indeed you will need the Geographic > coordinate system, and the distances then use Andoyer which is much more > precise. > > That is not included in the current Release. So if you need it you have to > download the Trunk of Boost, and it is there available as an extension. > > See the examples here: > > https://svn.boost.org/svn/boost/trunk/libs/geometry/example_extensions/gis/… > > Regards, Barend > > > > > ---------- Forwarded message ---------- > From: Sean Farrow <sean.farrow(a)seanfarrow.co.uk> > To: "boost-users(a)lists.boost.org" <boost-users(a)lists.boost.org> > Cc: > Date: Sun, 4 Mar 2012 17:13:21 +0000 > Subject: Re: [Boost-users] [Geometry] Calculating distances on the earth > > Hi: **** > > Ok, thanks, What (roughly) is the difference in precision? I’m using this > to determine the distance between two buildings.**** > > Cheers**** > > Sean.**** > > ** ** > > *From:* boost-users-bounces(a)lists.boost.org [mailto: > boost-users-bounces(a)lists.boost.org] *On Behalf Of *Barend Gehrels > *Sent:* 04 March 2012 17:02 > *To:* boost-users(a)lists.boost.org > *Subject:* Re: [Boost-users] [Geometry] Calculating distances on the earth > **** > > ** ** > > Hi Sean, > > On 4-3-2012 17:14, Sean Farrow wrote: **** > > Hi all:**** > > I need to calculate distances on the earth. Ideally I’d like to use the > haversine formula.**** > > There is an example in the docs at:**** > > > http://www.boost.org/doc/libs/1_49_0/libs/geometry/doc/html/geometry/quicks… > **** > > under the non-Cartesian heading.**** > > Will this do what I need, or do I need the Geographical coordinate system, > (if yes where is this available and what features does this supply?)**** > > > This will do what you ask for. So it will calculate distances on the Earth > using the Haversine formula. > > However, it considers the Earth as a perfect sphere, which it is not. So > distances are rough approximations. > > If you need more precise results indeed you will need the Geographic > coordinate system, and the distances then use Andoyer which is much more > precise. > > That is not included in the current Release. So if you need it you have to > download the Trunk of Boost, and it is there available as an extension. > > See the examples here: > > https://svn.boost.org/svn/boost/trunk/libs/geometry/example_extensions/gis/… > > Regards, Barend > > **** > > > ---------- Forwarded message ---------- > From: Barend Gehrels <barend(a)xs4all.nl> > To: boost-users(a)lists.boost.org > Cc: > Date: Sun, 04 Mar 2012 18:36:11 +0100 > Subject: Re: [Boost-users] [Geometry] Calculating distances on the earth > Hi Sean, > > On 4-3-2012 18:13, Sean Farrow wrote: > > Hi: **** > > Ok, thanks, What (roughly) is the difference in precision? I’m using this > to determine the distance between two buildings.**** > > > The sampes give an idea, but that is between cities (miles away). Between > buildings the difference will be less, but I've not tested it. So the best > is to test that yourself (and the results are interesting for the list ;-) ) > > Regards, Barend > > > > ---------- Forwarded message ---------- > From: Sean Farrow <sean.farrow(a)seanfarrow.co.uk> > To: "boost-users(a)lists.boost.org" <boost-users(a)lists.boost.org> > Cc: > Date: Sun, 4 Mar 2012 17:49:04 +0000 > Subject: Re: [Boost-users] [Geometry] Calculating distances on the earth > > Hi: **** > > I’ll test this and get back to the list. Do we have any idea as to > whether/when the extension(s) will become part of the official distribution? > **** > > Cheers**** > > Sean.**** > > *From:* boost-users-bounces(a)lists.boost.org [mailto: > boost-users-bounces(a)lists.boost.org] *On Behalf Of *Barend Gehrels > *Sent:* 04 March 2012 17:36 > *To:* boost-users(a)lists.boost.org > *Subject:* Re: [Boost-users] [Geometry] Calculating distances on the earth > **** > > ** ** > > Hi Sean, > > On 4-3-2012 18:13, Sean Farrow wrote: **** > > Hi: **** > > Ok, thanks, What (roughly) is the difference in precision? I’m using this > to determine the distance between two buildings.**** > > > The sampes give an idea, but that is between cities (miles away). Between > buildings the difference will be less, but I've not tested it. So the best > is to test that yourself (and the results are interesting for the list ;-) ) > > Regards, Barend**** > > If you are using latitude/longitude then these methods will work: 1) Consider implementing Vincentys method, proposed by Thaddeus Vincenty, and is documented at http://www.ngs.noaa.gov/PUBS_LIB/inverse.pdf, I believe this has a precision of around 0.5mm. Be careful to avoid domain errors near the poles. This has the advantage of also calculating forward and back azimuth. 2) Andoyer's method which also takes flattening into account but loses precision for very short distances. Alternatively since you are working with short distances implement Redfearn's formulae to generate UTM coordinates and then use planar geometry. For more information see: http://www.ga.gov.au/geodesy/datums/calcs.jsp#trans There is a pdf manual (containing all the formulae) ( http://www.icsm.gov.au/gda/gdatm/index.html) and excel worksheets along with on-line calculators that you can use here. Regards Andrew -- ___________________________________________ Andrew J. P. Maclean ___________________________________________

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[function_types] comparing arity
by Jeff Flinn 03 Mar '12

03 Mar '12

I'm trying to come up with the condition for an enable_if condition based on the function_arity of a signature. The following fails to compile: bool z = boost::mpl::equal_to < boost::function_types::function_arity<SIG>::value , boost::mpl::int_<3> >; Any help is appreciated. Thanks, Jeff

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