2008-12-01

COIN-OR (Computational Infrastructure for Operations Research) is an open source initiative for developing operations research software. It is home to several modeling frameworks and solvers for various types of problems (linear and nonlinear, continuous and discrete) written in languages such as C++ and Fortran.

Definr is a very fast dictionary, based on Princeton’s open WordNet. It uses Ruby on Rails and MySQL and achieves its speed by caching the top 10,000 definitions in memory and using a C extension for word completion.