doc of prob

doc/gf-history.html

@@ -12,11 +12,24 @@ Changes in functionality since May 17, 2005, release of GF Version 2.2
 
 </center>
 
+1/11 (AR) Yet another method for adding probabilities: append
+<tt> --# prob Double</tt> to the end of a line defining a function.
+This can be (1) a <tt>.cf</tt> rule (2) a <tt>fun</tt> rule, or
+(3) a <tt>lin</tt> rule. The probability is attached to the
+first identifier on the line.
+
+<p>
+
 31/10 (AR) Probabilistic grammars. Probabilities can be used to
 weight random generation (<tt>gr -prob</tt>) and to rank parse
 results (<tt>p -prob</tt>). They are read from a separate file
 (flag <tt>i -probs=File</tt>, format <tt>--# prob Fun Double</tt>)
 or from the top-level grammar file itself (option <tt>i -prob</tt>).
+<br>
+As a by-product, the probabilistic random generation algorithm is
+available for any context-free abstract syntax. Use the flag
+<tt>gr -cf<&tt>. This algorithm is much more efficient than the
+old (more general) one.
 
 <p>
 

examples/TWA.cf

@@ -1,4 +1,5 @@
 -- example of probabilistic grammar from Jurafsky & Martin p. 449
+-- AR 1/11/2005
 
 PredVP.  S   ::= NP VP ; --# prob 0.80 
 PredAux. S   ::= Aux NP VP ; --# prob 0.15

src/GF/Probabilistic/Probabilistic.hs

@@ -5,9 +5,9 @@
 -- Stability   : (stable)
 -- Portability : (portable)
 --
--- > CVS $Date: 2005/11/01 09:10:54 $ 
+-- > CVS $Date: 2005/11/01 09:20:09 $ 
 -- > CVS $Author: aarne $
--- > CVS $Revision: 1.4 $
+-- > CVS $Revision: 1.5 $
 --
 -- Probabilistic abstract syntax. AR 30\/10\/2005
 --
@@ -83,7 +83,7 @@ pProb s = case words s of
      "--#":"prob":f:p:_ | isDouble p -> [(zIdent f, read p)]
      f:ps@(g:rest) -> case span (/= "--#") ps of
        (_,_:"prob":p:_) | isDouble p -> [(zIdent f', readD p)] where 
-         f' = if f=="fun" then ident g else ident f
+         f' = if elem f ["fun","lin","data"] then ident g else ident f
        _ -> []
      _ -> []
   where