distributed config && float library

packages/gecode/examples/photo.yap

@@ -0,0 +1,80 @@
+%% -*- prolog -*-
+%%=============================================================================
+%% Copyright (C) 2011 by Denys Duchier
+%%
+%% This program is free software: you can redistribute it and/or modify it
+%% under the terms of the GNU Lesser General Public License as published by the
+%% Free Software Foundation, either version 3 of the License, or (at your
+%% option) any later version.
+%% 
+%% This program is distributed in the hope that it will be useful, but WITHOUT
+%% ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+%% FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+%% more details.
+%% 
+%% You should have received a copy of the GNU Lesser General Public License
+%% along with this program.  If not, see <http://www.gnu.org/licenses/>.
+%%=============================================================================
+
+:- use_module(library(gecode)).
+:- use_module(library(maplist)).
+
+% 5 people want to have a photograph together, but they have preferences.
+photo(Ex, Solution,Amount) :-
+	db(Ex, People, Preferences),
+	Space := space,
+	length(People, Len),
+	Len0 is Len-1,
+	People := intvars(Space,Len,0,Len0),
+	Space += distinct(People),
+	% Bools are the satisfied constraints
+	maplist(preferences(Space, Len), Preferences, Bools),
+	length(Preferences, PLen),
+	Sum := intvar(Space,0,PLen),
+	Space += linear(Bools,'IRT_EQ',Sum),
+	% add all satisfied constraints
+	Space += maximize(Sum),
+	Space += branch(People,'INT_VAR_SIZE_MIN','INT_VAL_MIN'),
+	SolSpace := search(Space),
+	Solution := val(SolSpace,People),
+	Amount := val(SolSpace,Sum).
+
+%reification, use with care
+preferences(Space, Len, X-Y, B) :-
+	NLen is -Len,
+	I0 := intvar(Space, NLen, Len),
+	I := intvar(Space, 0, Len),
+	B := boolvar(Space),
+	Space += reify(B, 'RM_EQV', R),
+	Space += linear([1,-1],[X,Y],'IRT_EQ', I0),
+	Space += abs(I0, I),
+	Space += rel(I, 'IRT_EQ', 1, R).
+
+
+db(s,[Alice,Bob,Carl,Deb,Evan], [Alice-Carl,
+		Carl-Deb,
+		Deb-Alice,
+		Evan-Alice,
+		Bob-Evan,
+		Carl-Evan,
+		Deb-Evan,
+		Evan-Bob]).
+
+db(l,[Betty,Chris,Donald,Fred,Gary,Mary,Paul,Peter,Susan],
+	[Betty-Donald,
+	 Betty-Gary,
+	 Betty-Peter,
+	 Chris-Gary,
+	 Chris-Susan,
+	 Donald-Fred,
+	 Donald-Gary,
+	 Fred-Betty,
+	 Fred-Gary,
+	 Gary-Mary,
+	 Gary-Betty,
+	 Mary-Betty,
+	 Mary-Susan,
+	 Paul-Donald,
+	 Paul-Peter,
+	 Peter-Susan,
+	 Peter-Paul]).