1/*
    2Distributional Clauses example.
    3From Example 4 of 
    4Davide Nitti, Tinne De Laet, and Luc De Raedt. Probabilistic logic programming for hybrid relational domains. Machine Learning 103(3), 407-449, 2016.
    5http://link.springer.com/article/10.1007/s10994-016-5558-8/fulltext.html
    6"We have an urn, where the number of balls n is a random variable and each ball 
    7X has a color, material, and size with a known distribution. 
    8The i-th ball drawn with replacement from the
    9urn is named drawn(i)."
   10See also
   11https://github.com/davidenitti/DC/blob/master/examples/tutorial.pl
   12*/
   13:- use_module(library(mcintyre)).   14
   15:- if(current_predicate(use_rendering/1)).   16:- use_rendering(c3).   17:- endif.   18:- mc.   19:- begin_lpad.   20
   21n(N): uniform(N,[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]).
   22color(X,C):uniform(C,[grey, blue, black]):-material(X, metal).
   23color(X,C):uniform(C,[black, brown]) :- material(X,wood).
   24material(X,M):finite(M,[wood:0.3,metal:0.7]) :- n(N), between(1, N, X).
   25drawn(_,B) : uniform(B,L):-n(N), findall(X, between(1, N, X), L).
   26size(X,S):beta(S,2, 3) :- material(X,metal).
   27size(X,S):beta(S,4, 2):-material(X,wood).
   28
   29
   30
   31:- end_lpad.