Google Summer of Code 2013

Welcome to the Boost C++ Libraries' home page for Google Summer of Code (GSoC). This page provides information about student projects, proposal submission templates, advice on writing good proposals, and links to information on getting started writing with Boost.

This year Boost is looking to fund work on a number of different kinds of proposals:

• toolkit-like extensions to existing libraries,
• finishing or extend sandbox libraries,
• new data structures and algorithms, and
• multiple competing proposals for the same project.

For projects involving new or experimental libraries, the process of getting source code "Boost-branded" can take much longer than a single summer. In many cases, it can take much longer than a single year. Even if a library is accepted, there is an expectation that the original author will continue to maintain it. Building a library as part of Boost can easily entail a multi-year commitment. For this reason, we are willing to consider multi-year GSoC projects. However, prospective students must limit the scope of their work to a single summer. We may invite the most successful students to re-apply in 2014.

Requirements

Students must submit a proposal. A template for the proposal can be found here here. Hints for writing a good proposal can be found here.

We strongly suggest that students interested in developing a proposal for Boost discuss their ideas on the mailing list in order to help refine the requirements and goals. Students who actively discuss projects on the mailing list are also ranked before those that do not.

Projects

The following projects have been suggested by potential mentors. If the descriptions of these projects seem a little vague... Well, that's intentional. We are looking for students to develop requirements for their proposals by doing initial background research on the topic, and interacting with the community on the mailing list to help identify expectations.

Projects from previous years can be found here. There are still a number of interesting projects found in these pages.

Boost.uBLAS

First of all, we have a page with the list of future and desired new features here: ​http://sourceforge.net/apps/mediawiki/ublas/index.php?title=Main_Page. Students are encourage to consult this page.

Boost.uBLAS http://www.boost.org/doc/libs/1_53_0/libs/numeric/ublas/doc/index.htm is a fast implementation of linear algebra procedures, of for short it's a vector and matrix library. Actually it's indeed a vector AND matrix library and this is one of the main problem. Vectors are matrices, at least in standard math textbook, but not in Boost.uBLAS. They are represented as 2 separate classes and do not share code really. Not enough to be efficient. Moreover, vector being considered as fixed-sized vectors, they are not as versatile as STL vectors (but it's not the same concept) and not as accurate as a true linear algebra vector, that is they do not implement the notion of being row-vector or column-vector.

Said like that, it's not that important you would say, but by merging vector and matrix classes, we could share a lot of code and optimize even further. Second of all, by having a unified architecture we could start implementing modern acceleration techniques that lacks in Boost.uBLAS, like SIMD computations, multi-core, GPU, etc...

Our ideas for a GSOC project are the following:

• unify representation of vector and matrices into a unique matrix class. Keep compatibility with previous code by providing a default vector<> representation that would inherit for matrix<>. Improve it too by adding more template parameters like size and orientation.
• add a framework for automatic algorithm selection at compile-time (that's more academic),
• add a framework for automatic algorithm selection at run-time (that's very academic, I'm thinking of matrix inversion etc...),
• use this new architecture to propose implementation for the following:
  • fixed-sized vectors and matrices with optimization
  • a true * operator for vector/vector, vector/matrix and matrix/matrix multiplication
  • an architecture to choose at compile time the best algorithm to apply if several are available (very relevant to multiplication for example),
  • ideas and examples on how to implement SIMD and multicore operations,
  • use this new framework to implement particular matrices like Toeplitz, Hadamard, block matrix (see a taxonomy and possible applications here: ​http://en.wikipedia.org/wiki/List_of_matrices) and select algorithms that are more specific to each type in order to optimize code even further.

The last feature is highly desirable in Machine Learning, Big Data, Computer Vision, Data mining, etc...

Inspiration from other libraries like Eigen, Armadillo, GotoBLAS, etc... is highly recommended (after all, that's one of the raison d'etre of Free Software).

Mentor: David Bellot (david.bellot[at]gmail.com)

Boost.Math Bernoulli numbers

Boost.Math http://www.boost.org/doc/libs/1_53_0/libs/math/doc/sf_and_dist/html/ is a large well-established Boost library, but new mathmetical functions can always be added.

We wonder if students would be interested in adding Bernoulli numbers needed in several useful series.

​http://en.wikipedia.org/wiki/Bernoulli_number

​http://mathworld.wolfram.com/BernoulliNumber.html

• Add support for Bernoulli numbers along with thread-safe caching.
• Add support for polygamma of positive integer order (requires Bernoulli numbers).
• Improve tgamma/lgamma for multiprecision types based on Stirling's approx.
• Optional: Add support for the Hurwitz zeta function.

This would clearly require some serious math skills, but also good knowledge of C++, especially using templates which Boost.Math makes much use of to provide not only built-in double and long double but recently multiprecision, large fixed and arbitrary precision.

If studying ​http://svn.boost.org/svn/boost/trunk/boost/math/special_functions/gamma.hpp leaves you frightened, then this project is not for you.

If you would like to demonstrate your skills, you might like to try coding the naive Akiyama–Tanigawa algorithm for second Bernoulli numbers Bn ​http://en.wikipedia.org/wiki/Bernoulli_number#Algorithmic_description using Boost.Math. Extra marks for providing a Boost.Test comparing with a handful of published values. You can use any platform, Linux, Mac or Microsoft with your IDE of choice, perhaps Visual Studio or NetBeans.

The project will by mentored by Paul Bristow for administration and Boost infrastructure, and John Maddock and Christopher Kormanyos for mathematical and algorithmic expertise.