/* 

  Reasoning in Belief Networks in Picat v3.

  This is a port of the belief networks program from
  I. Bratko, "Prolog Programming for Artificial Intelligence", 4th edn.,
  Pearson Education / Addison-Wesley 2012
  Page 378ff (Figure 16.4 and 16.5)
       
  The module belief_network_v3 is here:
  http://hakank.org/picat/belief_network_v3.pi


  This Picat model was created by Hakan Kjellerstrand, hakank@gmail.com
  See also my Picat page: http://www.hakank.org/picat/

*/

import belief_network_v3.

main => go.

go ?=>
  L = [
       [a,[]],
       [a,[c]],
       [c,[a]],
       [c,[a,d]],
       [e,[]],
       [e,[d]],
       [a,[b,c]],
       [a,[not c]]
  ],
  foreach(T in L)
    println(T),
    prob(T[1],T[2],P),
    println(p=P),
    nl
  end,
  nl.

go => true.


% Example from Exercise 16.4 (page 380)

parent(a,c).
parent(b,c).
parent(b,d).
parent(c,e).

p(a,0.1).
p(b,0.2).
p(c,[a,b],0.5).
p(c,[not a, b],0.0).
p(c,[a, not b],0.4).
p(d,[b],0.9).
p(d,[not b],0.1).
p(e,[c],0.6).
p(e,[not c],0.1).