Here is the weights file for the test:

% cat weights
T_A_a 1
R_S_A_B 10
F_B_b 100
L_C_c 50


Here's what the feature names mean:

preterminal feature:
T_A_a 1		means A is a preterminal, a is a terminal,
		and the feature for A appearing above a has weight 1.

rule feature:
R_S_A_B 10	means that the feature for the cfg rule S -> A B
		has weight 10.  S and B are added to the sets of nonterminals.

first word feature:
F_B_b 100	means that the feature for B appearing anywhere in the tree
      		with b as its first terminal has wieght 100.

last word feature:
L_C_c 50	means that the feature for C appearing anywhere in the tree
      		with c as its last terminal has weight 50.

Conventions: We have separate sets (unary) preterminals and (binary)
nonterminals.  Features for preterminals come first in the weights
file, and any symbol mentioned in these features is a preterminal.
Then come all other features, and all symbols in these features that
are not already declared as preterminals are nonterminals.



Some terminal strings to run the parser on:

% cat test
a a a
b a a a a a a
a a a a a a c





Now we'll go ahead and run the parser:

% ./parser.py weights test
13.0 (S (A a) (B (A a) (A a)))
506.0 (S (B (B (B (B (B (A b) (A a)) (A a)) (A a)) (A a)) (A a)) (A a))
256.0 (S (A a) (C (A a) (C (A a) (C (A a) (C (A a) (C (A a) (A c)))))))