Iterative algorithms which converge can be terminated with a maximum number
of iterations or a convergence threshold which stops computation when the
total change in scores is below a given delta.
If the command-line configuration specifies neither a number of iterations
nor a convergence threshold then a default number of iterations is used
with an infinite convergence threshold. Otherwise, when either value is
configured then an unset value is set to infinity.
An informal usage string. Parameter names are prefixed with "--".
Optional parameters are enclosed by "[" and "]".
Generic values are represented by all-caps with specific values enclosed
by "<" and ">".