pow-nroot.hpp
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/* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
/*
* Main authors:
* Vincent Barichard <Vincent.Barichard@univ-angers.fr>
*
* Copyright:
* Vincent Barichard, 2012
*
* This file is part of Gecode, the generic constraint
* development environment:
* http://www.gecode.org
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
namespace Gecode { namespace Float { namespace Arithmetic {
/*
* Bounds consistent square operator
*
*/
template<class A, class B>
forceinline
Pow<A,B>::Pow(Home home, A x0, B x1, int n)
: MixBinaryPropagator<A,PC_FLOAT_BND,B,PC_FLOAT_BND>(home,x0,x1), m_n(n) {}
template<class A, class B>
ExecStatus
Pow<A,B>::post(Home home, A x0, B x1, int n) {
if (n == 0) {
if ((x0.min() == 0.0) && (x0.max() == 0.0)) return ES_FAILED;
GECODE_ME_CHECK(x1.eq(home,1.0));
return ES_OK;
}
GECODE_ME_CHECK(x1.eq(home,pow(x0.domain(),n)));
if ((x1.min() == 0.0) && (x1.max() == 0.0)) {
GECODE_ME_CHECK(x1.eq(home,0.0));
return ES_OK;
}
if ((n % 2) == 0) {
if (x0.min() >= 0)
GECODE_ME_CHECK(x0.eq(home,nroot(x1.domain(),n)));
else if (x0.max() <= 0)
GECODE_ME_CHECK(x0.eq(home,-nroot(x1.domain(),n)));
else
GECODE_ME_CHECK(x0.eq(home,
hull(
nroot(x1.domain(),n),
-nroot(x1.domain(),n)
)
));
} else {
GECODE_ME_CHECK(x0.eq(home,nroot(x1.domain(),n)));
}
if (!x0.assigned()) (void) new (home) Pow<A,B>(home,x0,x1,n);
return ES_OK;
}
template<class A, class B>
forceinline
Pow<A,B>::Pow(Space& home, Pow<A,B>& p)
: MixBinaryPropagator<A,PC_FLOAT_BND,B,PC_FLOAT_BND>(home,p), m_n(p.m_n) {}
template<class A, class B>
Actor*
Pow<A,B>::copy(Space& home) {
return new (home) Pow<A,B>(home,*this);
}
template<class A, class B>
ExecStatus
Pow<A,B>::propagate(Space& home, const ModEventDelta&) {
if ((x0.min() == 0.0) && (x0.max() == 0.0)) return ES_FAILED;
GECODE_ME_CHECK(x1.eq(home,pow(x0.domain(),m_n)));
if ((x1.min() == 0.0) && (x1.max() == 0.0)) {
GECODE_ME_CHECK(x1.eq(home,0.0));
return home.ES_SUBSUMED(*this);
}
if ((m_n % 2) == 0) {
if (x0.min() >= 0)
GECODE_ME_CHECK(x0.eq(home,nroot(x1.domain(),m_n)));
else if (x0.max() <= 0)
GECODE_ME_CHECK(x0.eq(home,-nroot(x1.domain(),m_n)));
else
GECODE_ME_CHECK(x0.eq(home,
hull(
nroot(x1.domain(),m_n),
-nroot(x1.domain(),m_n)
)
));
} else {
GECODE_ME_CHECK(x0.eq(home,nroot(x1.domain(),m_n)));
}
return x0.assigned() ? home.ES_SUBSUMED(*this) : ES_FIX;
}
/*
* Bounds consistent square root operator
*
*/
template<class A, class B>
forceinline
NthRoot<A,B>::NthRoot(Home home, A x0, B x1, int n)
: MixBinaryPropagator<A,PC_FLOAT_BND,B,PC_FLOAT_BND>(home,x0,x1), m_n(n) {}
template<class A, class B>
ExecStatus
NthRoot<A,B>::post(Home home, A x0, B x1, int n) {
if (n == 0) return ES_FAILED;
GECODE_ME_CHECK(x0.gq(home,0.0));
GECODE_ME_CHECK(x1.eq(home,nroot(x0.domain(),n)));
GECODE_ME_CHECK(x0.eq(home,pow(x1.domain(),n)));
(void) new (home) NthRoot<A,B>(home,x0,x1,n);
return ES_OK;
}
template<class A, class B>
forceinline
NthRoot<A,B>::NthRoot(Space& home, NthRoot<A,B>& p)
: MixBinaryPropagator<A,PC_FLOAT_BND,B,PC_FLOAT_BND>(home,p), m_n(p.m_n) {}
template<class A, class B>
Actor*
NthRoot<A,B>::copy(Space& home) {
return new (home) NthRoot<A,B>(home,*this);
}
template<class A, class B>
ExecStatus
NthRoot<A,B>::propagate(Space& home, const ModEventDelta&) {
GECODE_ME_CHECK(x1.eq(home,nroot(x0.domain(),m_n)));
GECODE_ME_CHECK(x0.eq(home,pow(x1.domain(),m_n)));
return x0.assigned() ? home.ES_SUBSUMED(*this) : ES_FIX;
}
}}}
// STATISTICS: float-prop
Gecode::Actor
Base-class for both propagators and branchers.
Definition core.hpp:628
Gecode::Float::Arithmetic::NthRoot::NthRoot
NthRoot(Space &home, NthRoot &p)
Constructor for cloning p.
Definition pow-nroot.hpp:145
Gecode::Float::Arithmetic::NthRoot::propagate
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition pow-nroot.hpp:156
Gecode::Float::Arithmetic::NthRoot::m_n
int m_n
Definition arithmetic.hh:197
Gecode::Float::Arithmetic::NthRoot::copy
virtual Actor * copy(Space &home)
Create copy during cloning.
Definition pow-nroot.hpp:150
Gecode::Float::Arithmetic::NthRoot::post
static ExecStatus post(Home home, A x0, B x1, int n)
Post propagator for .
Definition pow-nroot.hpp:134
Gecode::Float::Arithmetic::Pow::m_n
int m_n
Definition arithmetic.hh:169
Gecode::Float::Arithmetic::Pow::post
static ExecStatus post(Home home, A x0, B x1, int n)
Post propagator for .
Definition pow-nroot.hpp:49
Gecode::Float::Arithmetic::Pow::propagate
virtual ExecStatus propagate(Space &home, const ModEventDelta &med)
Perform propagation.
Definition pow-nroot.hpp:95
Gecode::Float::Arithmetic::Pow::copy
virtual Actor * copy(Space &home)
Create copy during cloning.
Definition pow-nroot.hpp:89
Gecode::Float::Arithmetic::Pow::Pow
Pow(Space &home, Pow &p)
Constructor for cloning p.
Definition pow-nroot.hpp:84
Gecode::Home
Home class for posting propagators
Definition core.hpp:856
Gecode::MixBinaryPropagator< A, PC_FLOAT_BND, B, PC_FLOAT_BND >::x1
B x1
Definition pattern.hpp:209
Gecode::MixBinaryPropagator< A, PC_FLOAT_BND, B, PC_FLOAT_BND >::MixBinaryPropagator
MixBinaryPropagator(Space &home, MixBinaryPropagator &p)
Definition pattern.hpp:597
Gecode::MixBinaryPropagator< A, PC_FLOAT_BND, B, PC_FLOAT_BND >::x0
A x0
Definition pattern.hpp:207
Gecode::Propagator::Space
friend class Space
Definition core.hpp:1066
Gecode::Space::ES_SUBSUMED
ExecStatus ES_SUBSUMED(Propagator &p)
Definition core.hpp:3563
Gecode::ModEventDelta
int ModEventDelta
Modification event deltas.
Definition core.hpp:89
GECODE_ME_CHECK
#define GECODE_ME_CHECK(me)
Check whether modification event me is failed, and forward failure.
Definition macros.hpp:52
Gecode::Float::Arithmetic
Arithmetic propagators
Gecode::Float
Floating point numbers.
Gecode::Float::hull
FloatVal hull(const FloatVal &x, const FloatVal &y)
Definition val.hpp:507
Gecode::Float::PC_FLOAT_BND
const Gecode::PropCond PC_FLOAT_BND
Propagate when minimum or maximum of a view changes.
Definition var-type.hpp:292
Gecode
Gecode toplevel namespace
Gecode::ExecStatus
ExecStatus
Definition core.hpp:472
Gecode::ES_OK
@ ES_OK
Execution is okay.
Definition core.hpp:476
Gecode::ES_FIX
@ ES_FIX
Propagation has computed fixpoint.
Definition core.hpp:477
Gecode::ES_FAILED
@ ES_FAILED
Execution has resulted in failure.
Definition core.hpp:474
Gecode::pow
void pow(Home home, FloatVar x0, int n, FloatVar x1)
Post propagator for for $n\geq 0$.
Definition arithmetic.cpp:109
Gecode::nroot
void nroot(Home home, FloatVar x0, int n, FloatVar x1)
Post propagator for for $n\geq 0$.
Definition arithmetic.cpp:118
forceinline
#define forceinline
Definition config.hpp:187