PREDICTING: FILLING AN OUTPUT AVSPEC FROM
A HYPO AND AN INPUT AVSPEC

Every single learner must implement the
predict function, which is called xxx_predict
where xxx is the name of the learner.

   void xxx_predict(examples *exams,
                    ivec *in_att_nums,
                    ivec *out_att_nums,
                    char *params,
                    char *hypo,
                    avset *in,
                    avset *out)

Given the hypo, the parameters, and the input
avset, this fills in the predicted values in
the output avset.  The predicted values are
based only on the attributes in in_att_nums,
and predictions are only calculated for those
attributes in out_att_nums (if other
att_num's in "out" are defined, they are
unaffected by this operation).