LDPC-codes is a collection of programs and modules intended to support research and education concerning Low Density Parity Check (LDPC) codes. The decoding algorithm for LDPC codes is related to that used for Turbo codes, and to probabilistic inference methods used in other fields. Variations on LDPC and Turbo codes are currently the best practical codes known, in terms of their ability to transmit data at rates approaching channel capacity with very low error probability.
Libcolumbus is a small error tolerant search engine designed to deal with noisy data and typos. It will power the searches in the next generation of Ubuntu's HUD system as well as other searches. It has a fast implementation of the Levenshtein distance algorithm, which allows it to correct errors such as added and dropped letters (e.g. 'bar' -> 'bard'), changed letters ('ctr' -> 'car') and translations ('acr' -> 'car'). It also allows the user to customize the error values. Libcolumbus is designed to be small, efficient and easy to embed. It is programmed in C++ but also provides C and Python APIs.