April 2010 - Boost - lists.boost.org

[contract] Macro syntax?
by Lorenzo Caminiti 08 Apr '10

08 Apr '10

Hello all, I would like you to vote between one of the two options below. Which option do you prefer? (-) OPTION 1 requires programmers to repeat the function signature tokens twice -- in the function declaration and in the CONTRACT_FUNCTION() macro. (+) However, OPTION 1 seems to make the code more readable -- users not familiar with Boost.Contract can "skip" the tokens in the CONTRACT_FUNCTION() signature-sequence and just read the usual C++ function declaration. OPTION 1: The function declaration is programmed using the usual C++ syntax just before the CONTRACT_FUNCTION() macro. template<typename T> class myvector { CONTRACT_INVARIANT( ({ ... }) ) public: void push_back(const T& element) // Usual C++ push_back() declaration. CONTRACT_FUNCTION( (class) (copyable)(myvector) (public) (void) (push_back)( (const T&)(element) ) (precondition)({ ... }) (postcondition)({ ... }) (body)({ ... }) ) ... }; OPTION 2: The CONTRACT_FUNCTION() macro automatically programs also the function declaration. template<typename T> class myvector { CONTRACT_INVARIANT( ({ ... }) ) public: // No usual C++ push_back() declaration here. CONTRACT_FUNCTION( (class) (copyable)(myvector) (public) (void) (push_back)( (const T&)(element) ) (precondition)({ ... }) (postcondition)({ ... }) (body)({ ... }) ) ... }; Thank you. Lorenzo

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[Review Results] Boost.Polygon library accepted into boost
by Fernando Cacciola 08 Apr '10

08 Apr '10

Dear Boosters, [first of all allow me to apology for not doing this before. My small consulting bussines suddenly grew out of proportion and now is way over my head, keeping me working/managing 16 hours a day] I am pleased to announce that the Boost.Polygon library from Lucanus Simonson has been accepted into boost provided some of the most critical concerns, detailed below, are addressed first. First of all I would like to thank Lucanus and Intel Corporation for making this work available to all C++ developers around the world. I would also like to thank all the reviewers that participated (in no particular order nor degree of participation) Thomas Klimpel Frank Mori Hess Barend Gehrels Andreas Fabri Jeffrey Hellrung Tim Keitt Markus Werle Paul A. Bristow Robert Stewart Mathias Gaunard Michael Fawcett Steven Watanabe Joachim Faulhaber John Bytheway Sebastian Redl Mika Heiskanen John Phillips Kai Benndorf Hartmut Kaiser Arash Partow Maurizio Vitale Brandon Kohn David Abrahams Gordon Woodhull Daniel James John Maddock Tom Brinkman Bo Persson Mateusz Loskot Christian Henning Jean-Sebastien Stoezel The library had 6 yes votes and 4 no votes. Those who voted no made the following major complains and remarks (they are numbered as I will refer to them back later): Barend Gehrels: (1) According to his benchmarks, intersection algorithms are unnecesarily slow as if something where fundamentally wrong in the design and/or implementation. AFAICT the implication has not been proved or disproved so far, hence I consider it a red herring and cannot take it as a reason for rejecting the library, but it is important to look at it in detail. (2) As a major complain, the library is unusable in those domains where floating point support is a requirement (like GIS). (3) The library should contain some basic polygon geometry algorithms such as convex hull and centriod Phil Endecott: (4) There is no concept checking in the code so it is difficult to adapt. (5) There where too many warnings and build errors (but Luke fixed these) (6a) The documentation needs a better overview of operations supported by the concetps. (6b) It also needs the details on the algorithms complexities. (6c) It also misses the numerical requirements for the coordinate type. (6d) And tutorials. (7) Some operators are ambiguous and it would be better to keep just one of each "flavor". (8) The polygon_data template class is parameterized by a coordiante type rather than a point type. This makes it useless for integration with existing geometric data types Michael Fawcett: (5), (6a), (6d) (9) T9he API should provide versions using output iterators in addition to output container references. (10) Theoreticall the library would be usable with a user defined coordinate type (metting certain requirements now undocumented), for example a fixed point data type, but some details in the internal design and implementation prevents this. (11) As a major complain, the library is unusable in those domains where floating point support is a requirement (like GIS). Hartmut Kaiser: (11), (1) Fernando Cacciola: (12) The name of the library should change to better indicate that is restricted to Integral coordinates and two-dimensions. (13) The documentation must contain a "credits" section acknowledging all the people that participated in the review. For the library to be effectively accepted, points (5),(6a-d),(10), (12) and (13) should properly addressed ((5) is already done AFAICT) It would be quite significant if point (1) where looked into. Once again I thank Lucanus, Intel Corporation and all the reviwers. Best regards -- Fernando Cacciola SciSoft Consulting, Founder http://www.scisoft-consulting.com

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Re: [boost] [msm] new version available
by Christophe Henry 07 Apr '10

07 Apr '10

>>>> Hi all, >>>> >>>> I just finished the newest MSM version. Unfortunately, I'm afraid I'm >>>> a bit late to get it shipped with boost v1.43 but at least it will >>>> give us time to have a look at it. >>>> What is new: >>>> - the doc was rewritten almost from the ground up. >>> <snip> >>>> You can find the new version, like always: >>>> - in the Vault (http://www.boostpro.com/vault/index.php?directory=Msm) >>>> - in the sandbox (http://svn.boost.org/svn/boost/sandbox/msm/) >>>> >>>> Regards, >>>> >>>> Christophe >>> >>> Hi, >>> >>> Just a form remark. We use to see the code highlighted. Have you the possibility to highligth the code? >>> >>> Best, >>> Vicente >> >> >> Done and committed in the Sandbox. > > Hi, I see that you used <programlisting>. Shouldn't you use <programlisting language="c++"> or somthing like that? > > Best, > Vicente I could but as I didn't see any difference in the generated html, I suppose it is an unimportant attribute. Regards, Christophe

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Crypto Library
by Chad Seibert 07 Apr '10

07 Apr '10

> Hi, > > I've just got confirmation from Jack Lloyd that I can port Botan to Boost. He only uses Boost.Python currently because he was having issues with shared_ptr when compiling for ARM. However, I think that most of these issues will be resolved (or have been) when the porting process takes place. Is there any protocol for porting an entire library to Boost? I know that ASIO took a while for approval. > So I'm going to ask a heretical question: why do you/he want to add it > to Boost? > Please don't make it header only in the process or I will be forced to > look at CryptoPP which is guaranteed to make babies cry. I was just getting a community response to porting a library, in this case Botan, vs constructing a library from scratch. Given that Botan is not heavily templatized, so there shouldn't be a reason this lib is headers only. However, any specializations will have to be. Tomorrow morning I'll have a draft proposal up for peer review. Many thanks for your input, Chad Seibert _________________________________________________________________ The New Busy is not the old busy. Search, chat and e-mail from your inbox. http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:ON:…

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Porting Botan to Boost
by Chad Seibert 07 Apr '10

07 Apr '10

Hi, I've just got confirmation from Jack Lloyd that I can port Botan to Boost. He only uses Boost.Python currently because he was having issues with shared_ptr when compiling for ARM. However, I think that most of these issues will be resolved (or have been) when the porting process takes place. Is there any protocol for porting an entire library to Boost? I know that ASIO took a while for approval. Thanks, Chad _________________________________________________________________ Hotmail has tools for the New Busy. Search, chat and e-mail from your inbox. http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:ON:…

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[GSoC] Binomial and Fibonacci heap implementation project
by Суворов Дмитрий 07 Apr '10

07 Apr '10

Hello, My name is Dmitriy. I'd like to participate in GSoC2010 with the Boost project. I looked through you ideas list, and I think i could do Binomial heap and Fibonacci heap as a summer project. I've composed a draft of my proposal, could you comment on it? My name is Dmitriy Suvorov. I'm a student of Bauman Moscow State Technical University. I am a third course student of a Robotics department. My degree program is BS. My email is dmitriy_suvorov(a)inbox.ru. I don't have any homepage. I plan to spend 5-5.5 hours per day on coding in June and 8 hours per day in July and August. I plan to start coding on May 24th. And I am going to stop coding on 30th August. I can't spend more time in June because I have university's exams. I think I won't spend much time on coding in September because university courses will start. But I am going to continue my work on Boost library in autumn. My middle degree in university is 4.76 (maximum is 5.0). I've taken courses in mathematics, programming and electronics. I'm interested in coding with application of mathematical algorithms. Now I'm working on robotics computer vision to participate in international competitions "Eurobot 2010". I'm going to take part in open source project for the first time. I'm interested in contributing to the Boost C++ Libraries and I want to gain an experience in programming. I'd like to solve interesting problems. I have knowledge about data structures and want to apply my knowledge in practice. I'm going to read more information about data structures and Boost C++ Libraries in May. My rates, from 0 to 5 (0 being no experience, 5 being expert), of my knowledge of the following languages, technologies, or tools: C++ - 5 C++ Standard Library - 5 Boost C++ Libraries - 3 Subversion - 4 I like Visual Studio to write Windows programs and KDevelop to write Linux programs. The most familiar software documentation tool with me is Doxygen. I want to work on binomial heap. If I'll solve problem quickly I want to work on other data structure, for example, on Fibonacci heap. Binomial heap is implementation of the mergeable heap abstract data type which is a priority queue supporting merge operation. Binomial heap is a collection of binomial trees. A binomial tree is defined recursively: - A binominal tree of order 0 is a single node. - A binomial tree of order k has a root node whose children are roots of binomial trees of orders k-1, k-2, +, 1, 0. All operations work on O(log n) time on a binomial heap with n elements. Fibonacci heap is a heap data structure consisting of a forest of trees. It has a better amortized running time than a binomial heap. These heaps are used in to improve asymptotic time of important algorithms, such as Dijkstra's algorithm for computing shortest path in a graph, and Prim's algorithm for computing a minimum spanning tree of a graph. I have found implementations of binomial heap in C and Python at LITMUS project. The homepage of project is www.cs.unc.edu/~anderson/litmus-rt/ . I'm going to create a new class for the Binominal heap and polish current implementation of Fibonacci heap. I will use Introduction to algorithms by Cormen, Leiserson as a reference. Could you review this?

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Re: [boost] [msm] new version available
by Christophe Henry 07 Apr '10

07 Apr '10

>> Hi all, >> >> I just finished the newest MSM version. Unfortunately, I'm afraid I'm >> a bit late to get it shipped with boost v1.43 but at least it will >> give us time to have a look at it. >> What is new: >> - the doc was rewritten almost from the ground up. > <snip> >> You can find the new version, like always: >> - in the Vault (http://www.boostpro.com/vault/index.php?directory=Msm) >> - in the sandbox (http://svn.boost.org/svn/boost/sandbox/msm/) >> >> Regards, >> >> Christophe > > Hi, > > Just a form remark. We use to see the code highlighted. Have you the possibility to highligth the code? > > Best, > Vicente Done and committed in the Sandbox. Thanks for your help, Christophe

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Re: [boost] [GSoC] Heaps & Queues (draft proposal)
by iaml 07 Apr '10

07 Apr '10

First of all, thank you, Andrew and Luke, for pointing out my mistakes and misunderstanding in my draft project which I sent several days ago. After that, I have read some source code in the STL and do some more research on this topic. Now, I work out my draft proposal again. Please feel free to point out my stupidity. I will be very grateful for this. Besides, I still have some doubt on this project: What we need to do in this project is to build a new library as the result of decoupling boost/pending from the BGL. So the compatibility with the new library and the BGL need to be concerned. However, I have read the document in the BGL. It’s said that we can convert existing graphs to the BGL by implementing some functions. Dose it mean the APIs of the new library does not effect the compatibility of the new library and the BGL since we can change it properly. Is that right? ==== draft proposal v0.2 ==== Project Proposal * Please provide a description of your proposed work. ** Background There are a number of data structures in boost/pending that implement different kinds of heaps and queues that are used in a number of different Boost Graph (BGL) algorithms. These can be cleaned up, decoupled from the BGL and redeveloped into a useful library for advanced data structures. Why don’t we use them directly? We can’t use boost/pending or libs/pri_queue as the new library directly for several reasons: 1. Heaps don’t parameterize for container type. They use vector as default. In the STL, there is very clear abstraction between containers and algorithms (they use iterator to achieve this abstraction). Since abstraction is a goal of the project, it’s necessary to modify the data structure in boost/pending rather than use it directly. 2. The APIs designed in the boost/pending is not user-friendly. In my opinion, the heaps in boost/pending act as the container of the priority queue rather than as a data structure. So some operations are omitted since they are useless in priority queue, but useful in heap and maybe necessary for other adaptors. They lack some operations such as delete one key (not just pop the minimum or maximum key), update the key in heap. This leads to the necessity of redeveloping a new library. ** Benefit for Boost Heap is widely used in development such as heap sort, priority queue and other graph algorithm. It also can be the container for advanced data structures. But the heaps in boost/pending and libs/pri_queue is not extendable or highly abstract. This leads to the limited usage of this library. To redevelop a new library about heaps and priority queue more abstract and more user-friendly not only can broaden the user group of Boost, but also can fix the design deficiency in boost/pending and make it more conforms to the philosophy of Boost. ** Solution In my opinion, most of work is to rewrite and reuse the existing data structures in boost/pending and libs/pri_queue. The most important thing I should consider is the APIs design of the new library. It should be highly abstract and user-friendly. The compatibility with the new library and the BGL needs to be concerned. *In order to be extendible, I would like to add iterator to the base class, which is more frequently used in programming, especially generic programming, than pointer. In some libraries, such as the STL, iterator is a bridge for container and algorithm. Since one of the goals of this project is to redevelop a new library for advance data structures and adaptors, I consider iterator to be necessary component to the library. Maybe it’ll take a little bit more memory, but in modern PCs, I think it acceptable.(am I wrong about the usage of the iterator?)* * * Besides the heaps required, I would like to add d-ary heap into the new library. Because d-ary heap is a variation of binary heap (so I can use binary heap as a special case for d-ary) and has faster running time. If time permits, I want to add splay heap (because it has the attractive property that recently accessed elements are quick to access again. I think it will be very useful in application software programming) and other heaps mentioned in libs/pri_queue into the new library. Below is my design to the library APIs. template <class RandomAccessIterator, // iterator of the container class TreeNode, // key type class Comp = std::less<TreeNode>> class heap{ public: class iterator{ // implement iterator so that this class can be use as container // for other adaptors and algorithms public: TreeNode const& operator* () const; TreeNode const* operator->() const; iterator& operator++(); iterator operator++(int); bool operator== (iterator const& it); bool operator!= (iterator const& it); }; public: /* param: new_inserted points to the bottom of the container * where the new value has been inserted but not heapify. */ void insert(RandomAccessIterator new_inserted); void delete(RandomAccessIterator delete_node); void update(RandomAccessIterator update_node, TreeNode& new_node); // make the heap mutable RandomAccessIterator merge(RandomAccessIterator other_root); RandomAccessIterator getRoot(); RandomAccessIterator find(TreeNode& node); bool empty() const; size_type size() const; iterator begin() const; iterator end() const; void print() const; private: void print_recur() const; protected: RandomAccessIterator _root; }; NOTICE: operations print and print_recur is optional. But I prefer to include them because it'll be helpful when debugging the programs using this library. The class mentioned above is the base class for all the heap structures in the new library. The classes such as Fibonacci heap, relaxed heap, binomial heap and d-ary heap should inherit from this abstract class and add additional operations if needed. As the adaptor of heaps, the priority queue API may like: template< class RandomAccessIterator, class TreeNode, class Comp = std::less<TreeNode> class Container = fibonacci_heap<RandomAccessIterator, TreeNode, Comp>> class priority_queue{ public: /* param: new_inserted points to the place * where the new value has been inserted */ void push(RandomAccessIterator new_inserted); void pop(); // get the first value without popping it const TreeNode& front() const; TreeNode& front() ; RandomAccessIterator front() const; RandomAccessIterator find(TreeNode& node); void update(RandomAccessIterator update_node, TreeNode& new_node); // make the priority queue mutable RandomAccessIterator merge(RandomAccessIterator other_head); bool empty() const; size_type size() const; void print() const; private: void print_recur() const; protected: RandomAccessIterator _head; }; Thank you for reading

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Gsoc Boost.Graph: implementing new algorithms
by Camillo Anania 07 Apr '10

07 Apr '10

Hi guys, I'm developing my thesis using BGL. Now it's some months I'm working on it and this is what I would like to see implemented on BGL and partially what I'm working on in those months: - check if graph have an euler tour(is eulerian) and find one and/or all possible euler tours - add the support for mixed graph - add the algorithm to find a minimum cost maximum matching I would like to know an opinion about that. Thanks Camillo

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Crypto Suite
by Chad Seibert 07 Apr '10

07 Apr '10

> Hi, > > I was looking through previous GSoC ideas and I was interested in doing a crypto suite as described here: > > http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl?Google_Summe… > > I was wondering if this was still in high demand, as I've been tied between doing this and the BigInt library proposed on the ideas page. The only reason I ask is because I'd like to do the most good for this project and wonder which project that might be. > > Thank you for any input, > Chad Seibert > > _________________________________________________________________ > Hotmail is redefining busy with tools for the New Busy. Get more from your inbox. > http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:ON:… > _______________________________________________ > Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost > > Sure you want to do this from scratch? Botan uses Boost - why not ask > Jack Lloyd if he'd let you pull bits of it down into Boost? Well, as I'm writing the proposal, I'm more emphasizing the structure of generic implementations of crypto-like stuff, not the actual implementations of MD5, AES, RSA, etc. The second half of my proposal was on actual implementation, where I discuss using either Crypto++ or Botan, with author permission. I'm in the midst of getting that permission. _________________________________________________________________ The New Busy is not the too busy. Combine all your e-mail accounts with Hotmail. http://www.windowslive.com/campaign/thenewbusy?tile=multiaccount&ocid=PID28…

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