// -*- C++ -*-
// $Id: fermbc.h,v 1.7 2004-09-22 17:24:59 bjoo Exp $
/*! @file
* @brief Fermion action boundary conditions
*/
#ifndef __fermbc_h__
#define __fermbc_h__
using namespace QDP;
#include "gaugebc.h"
#include "handle.h"
namespace Chroma
{
//! Base class for all gauge action boundary conditions
/*! @ingroup actions
*
*/
template<class T>
class FermBC
{
public:
//! Virtual destructor to help with cleanup;
virtual ~FermBC() {}
//! Modify U fields according to the fermion BC in place
virtual void modifyU(multi1d<LatticeColorMatrix>& u) const = 0;
//! Modify fermion fields in place
virtual void modifyF(T& psi) const = 0;
//! Says if there are fermion non-trivial
virtual bool nontrivialP() const = 0;
};
//! Abstract class for all gauge action boundary conditions with Schroedinger BC
/*! @ingroup actions
*
* Schroedinger BC implies periodic in dirs orthog to decay dir, and some
* kind of fixed BC in the decay dir.
*/
template<class T>
class SchrFermBC : public FermBC<T>
{
public:
//! Virtual destructor to help with cleanup;
virtual ~SchrFermBC() {}
};
//! Concrete class for 1-link gauge action boundary conditions with Schroedinger BC
/*! @ingroup actions
*
* Schroedinger BC for gauge actions that have only 1 link for padding
* in the decay direction - e.g., Wilson-like gauge action
*/
template<class T>
class Schr1LinkFermBC : public SchrFermBC<T>
{
public:
//! Schroedinger BC
/*!
* \param gbc_ a 1-link Schroedinger GAUGE BC
* \param theta_ twist angle for BC
*/
Schr1LinkFermBC(const Schr1LinkGaugeBC& gbc_, const Real& theta_) : gbc(gbc_)
{init(theta);}
//! Copy constructor
Schr1LinkFermBC(const Schr1LinkFermBC& a) : gbc(a.gbc), mask(a.mask), fld(a.fld) {}
//! Destructor is automatic
~Schr1LinkFermBC() {}
//! Assignment
Schr1LinkFermBC& operator=(const Schr1LinkFermBC& a)
{gbc = a.gbc; mask = a.mask; fld = a.fld; return *this;}
//! Modify U fields in place
void modifyU(multi1d<LatticeColorMatrix>& u) const
{QDP_error_exit("modifyU not implemented");}
//! Modify fermion fields in place
void modifyF(T& psi) const
{QDP_error_exit("modifyF not implemented");}
//! Says if there are fixed links within the lattice
bool nontrivialP() const {return true;}
protected:
void init(const Real& theta);
private:
// Hide default constuctor and operator=
Schr1LinkFermBC() {}
private:
Schr1LinkGaugeBC gbc;
multi1d<LatticeBoolean> mask;
multi1d<LatticeColorMatrix> fld;
};
//! Concrete class for 2-link gauge action boundary conditions with Schroedinger BC
/*! @ingroup actions
*
* Schroedinger BC for gauge actions that have only 2 links for padding
* in the decay direction - e.g., Symanzik-like gauge action
*/
template<class T>
class Schr2LinkFermBC : public SchrFermBC<T>
{
public:
//! Schroedinger BC
/*!
* \param gbc_ a 2-link Schroedinger GAUGE BC
* \param theta_ twist angle for BC
*/
Schr2LinkFermBC(const Schr2LinkGaugeBC& gbc_, const Real& theta_) : gbc(gbc_)
{init(theta);}
//! Copy constructor
Schr2LinkFermBC(const Schr2LinkFermBC& a) : gbc(a.gbc), mask(a.mask), fld(a.fld) {}
//! Destructor is automatic
~Schr2LinkFermBC() {}
//! Assignment
Schr2LinkFermBC& operator=(const Schr2LinkFermBC& a)
{gbc = a.gbc; mask = a.mask; fld = a.fld; return *this;}
//! Type of Schroedinger BC
SchrFunType getSFermBC() const {return SchrFun;}
//! Modify U fields in place
void modifyU(multi1d<LatticeColorMatrix>& u) const
{QDP_error_exit("modifyU not implemented");}
//! Modify fermion fields in place
void modifyF(T& psi) const
{QDP_error_exit("modifyF not implemented");}
//! Says if there are fixed links within the lattice
bool nontrivialP() const {return true;}
protected:
void init(const Real& theta);
private:
// Hide default constuctor and operator=
Schr2LinkFermBC() {}
private:
Schr2LinkGaugeBC gbc;
multi1d<LatticeBoolean> mask;
multi1d<LatticeColorMatrix> fld;
};
//! Concrete class for all gauge actions with trivial boundary conditions
/*! @ingroup actions
*
* No BC
*/
template<class T>
class PeriodicFermBC : public FermBC<T>
{
public:
//! Only full constructor
PeriodicFermBC() {}
//! Copy constructor
PeriodicFermBC(const PeriodicFermBC& a) {}
//! Destructor is automatic
~PeriodicFermBC() {}
//! Assignment
PeriodicFermBC& operator=(const PeriodicFermBC&) {return *this;}
//! Modify U fields in place
/*! NOP */
void modifyU(multi1d<LatticeColorMatrix>& u) const {}
//! Modify fermion fields in place
/*! NOP */
void modifyF(T& psi) const {}
//! Says if there are non-trivial BC links
bool nontrivialP() const {return false;}
};
//! Concrete class for all gauge actions with simple boundary conditions
/*! @ingroup actions
*
* Simple BC, where boundary array is multiplied on the links on the
* edge of the lattice
*/
template<class T>
class SimpleFermBC : public FermBC<T>
{
public:
//! Only full constructor
/*!
* \param boundary multiply links on edge of lattice by boundary
*
* NOTE: there is no real reason this is of type int, could be more general
* like Complex
*/
SimpleFermBC(const multi1d<int>& boundary_) :
gbc(new PeriodicGaugeBC()), boundary(boundary_)
{init();}
//! Use both a Gauge BC and a boundary field
/*!
* \param gbc A simple Gauge BC
* \param boundary multiply links on edge of lattice by boundary
*
* The type of gbc is restricted here mainly for paranoia.
* The type could be loosened (in fact to an abstract type), but it makes
* no sense to apply these type FermBC to a Schr1LinkGaugeBC, for example.
*
* Currently, no code uses this capability...
*/
SimpleFermBC(const SimpleGaugeBC& gbc_, const multi1d<int>& boundary_) :
gbc(new SimpleGaugeBC(gbc_)), boundary(boundary_)
{init();}
//! Copy constructor
SimpleFermBC(const SimpleFermBC& a) :
gbc(a.gbc), boundary(a.boundary), nontriv(a.nontriv) {}
//! Destructor is automatic
~SimpleFermBC() {}
//! Assignment
SimpleFermBC& operator=(const SimpleFermBC& a)
{gbc = a.gbc; boundary = a.boundary; nontriv = a.nontriv; return *this;}
//! Modify U fields in place
void modifyU(multi1d<LatticeColorMatrix>& u) const
{
gbc->modify(u); // first modify the U fields
if (nontrivialP())
{
// phases for all the directions
for(int m = 0; m < Nd; ++m)
{
/* u[m] *= (coord(m) == nrow(m)-1 ) ? boundary[m] : 1 */
u[m] *= where(Layout::latticeCoordinate(m) == Layout::lattSize()[m]-1,
Integer(boundary[m]), Integer(1));
}
}
}
//! Modify fermion fields in place
/*! NOP */
void modifyF(T& psi) const {}
//! Says if there are non-trivial BC links
bool nontrivialP() const {return nontriv;}
protected:
void init()
{
// Check triviality of boundary
nontriv = false;
for(int m = 0; m < Nd; ++m)
if (boundary[m] != 1)
nontriv |= true;
}
private:
// No empty constructor
SimpleFermBC() {}
private:
Handle<GaugeBC> gbc;
multi1d<int> boundary;
bool nontriv;
};
}
using namespace Chroma;
#endif