This directory contains code for various machine-learning
algorithms.  All operate on binary features and produce
binary classifications.

Partly for historical reasons, the input file format is as
follows.  First, an optional line contains the number of
instances and number of attributes per instance.  This is a
historical relic, and normally ignored.  Next come
instances, one per line, of the format
  name class attrs
where name is an arbitrary identifier containing no
whitespace, class is either 1 or -1 (yes, ugly), and
attrs is a bit vector of Boolean attributes, e.g. 11010.

There is a library here, and also a driver program.  The
library interface is fairly straightforward, and you can
examine the driver code to understand it better.

The driver program can serve as both a learner and a
classifier.  In learning mode, it reads an instance file
from standard input and produces a file containining learned
knowledge for some algorithm.  In classification mode, the
driver uses a knowledge file to classify or check an
instance file presented on standard input.  There are
generic driver program options, and also per-learner
options; invoke as "learner -a foo -h" to see the latter.

There are probably a million bugs and misfeatures.  Notes on
these would be appreciated.

    Bart Massey
    Mick Thomure
    2005/11/13