div.hpp

00001 /* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
00002 /*
00003  *  Main authors:
00004  *     Guido Tack <tack@gecode.org>
00005  *     Vincent Barichard <Vincent.Barichard@univ-angers.fr>
00006  *
00007  *  Copyright:
00008  *     Guido Tack, 2008
00009  *     Vincent Barichard, 2012
00010  *
00011  *  This file is part of Gecode, the generic constraint
00012  *  development environment:
00013  *     http://www.gecode.org
00014  *
00015  *  Permission is hereby granted, free of charge, to any person obtaining
00016  *  a copy of this software and associated documentation files (the
00017  *  "Software"), to deal in the Software without restriction, including
00018  *  without limitation the rights to use, copy, modify, merge, publish,
00019  *  distribute, sublicense, and/or sell copies of the Software, and to
00020  *  permit persons to whom the Software is furnished to do so, subject to
00021  *  the following conditions:
00022  *
00023  *  The above copyright notice and this permission notice shall be
00024  *  included in all copies or substantial portions of the Software.
00025  *
00026  *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
00027  *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
00028  *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
00029  *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
00030  *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
00031  *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
00032  *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00033  *
00034  */
00035 
00036 namespace Gecode { namespace Float { namespace Arithmetic {
00037 
00038   /*
00039    * Bounds consistent division operator
00040    *
00041    */
00042   template<class A, class B, class C>
00043   forceinline
00044   Div<A,B,C>::Div(Home home, A x0, B x1, C x2)
00045     : MixTernaryPropagator<A,PC_FLOAT_BND,B,PC_FLOAT_BND,C,PC_FLOAT_BND>(home,x0,x1,x2) {}
00046 
00047   template<class A, class B, class C>
00048   forceinline
00049   Div<A,B,C>::Div(Space& home, Div<A,B,C>& p)
00050     : MixTernaryPropagator<A,PC_FLOAT_BND,B,PC_FLOAT_BND,C,PC_FLOAT_BND>(home,p) {}
00051 
00052   template<class A, class B, class C>
00053   Actor*
00054   Div<A,B,C>::copy(Space& home) {
00055     return new (home) Div<A,B,C>(home,*this);
00056   }
00057 
00058   template<class A, class B, class C>
00059   ExecStatus
00060   Div<A,B,C>::post(Home home, A x0, B x1, C x2) {
00061     GECODE_ME_CHECK(x2.eq(home,x0.domain() / x1.domain()));
00062     GECODE_ME_CHECK(x0.eq(home,x2.domain() * x1.domain()));
00063     (void) new (home) Div<A,B,C>(home,x0,x1,x2);
00064     return ES_OK;
00065   }
00066 
00067   template<class A, class B, class C>
00068   ExecStatus
00069   Div<A,B,C>::propagate(Space& home, const ModEventDelta&) {
00070     if (x1.assigned() && (x1.val() == 0)) return ES_FAILED;
00071     GECODE_ME_CHECK(x2.eq(home,x0.domain() / x1.domain()));
00072     GECODE_ME_CHECK(x0.eq(home,x2.domain() * x1.domain()));
00073     if (!x2.assigned() || (x2.val() != 0.0))
00074       GECODE_ME_CHECK(x1.eq(home,x0.domain() / x2.domain()));
00075     return (x0.assigned() && x1.assigned()) ? home.ES_SUBSUMED(*this) : ES_NOFIX;
00076   }
00077 
00078 }}}
00079 
00080 // STATISTICS: float-prop
00081