chains

Word-level Markov chains in C.

Train a trigram Markov model and use it to generate text.

Installation

with clib:

clib install clehner/chains

via git:

git clone https://github.com/clehner/chains.git
cd chains
make install

Usage

chains [options]

Options:

• -v Output program usage.
• -h Output help information.
• -f corpus_file Read the given file and learn each line.
• -d Output the markov model data structure.
• -s seed_num Seed the random number generator.
• -l Learn each query before responding to it.

chains will read the corpus file(s) given with the -f options, and then interactively respond to queries on standard I/O. Responses are generated that include an n-gram from the query, or include a smaller sequence if the model does not include any n-grams from the query.

Example:

The user's queries and the program's responses alternate line by line, until the user ends the execution by pressing ^D.

$ chains -f LICENSE
> GNU
of the GNU Lesser 
> You may 
You may convey a covered work under sections 3 and 4 of this License.
> 
If the Library that is part of the GNU GPL.

Upon receiving an empty line as a query, chains will pick an n-gram from the model to start the sequence.

The license isn't the best example since it produces incomplete sentences, as the file is line-wrapped. For a more interesting example, try chaino with an IRC channel log.

API

chains can be used as a library. See the header file.

Todo

• Allow changing N, the order of the model.
• Improve space efficiency.
• Use Katz's back-off, Kneser-Ney smoothing, or something.
• Allow looking up the probability of a sequence based on the model.
• Document the API.