helib::PAlgebraMod Class Reference

The structure of Z[X]/(Phi_m(X), p) More...

#include <PAlgebra.h>

Public Member Functions
	PAlgebraMod (const PAlgebra &zMStar, long r)
template<typename type >
const PAlgebraModDerived< type > &	getDerived (type) const
const PAlgebraModCx &	getCx () const
bool	operator== (const PAlgebraMod &other) const
bool	operator!= (const PAlgebraMod &other) const
PA_tag	getTag () const
	Returns the type tag: PA_GF2_tag or PA_zz_p_tag. More...
const PAlgebra &	getZMStar () const
	Returns reference to underlying PAlgebra object. More...
const std::vector< NTL::ZZX > &	getFactorsOverZZ () const
	Returns reference to the factorization of Phi_m(X) mod p^r, but as ZZX's. More...
long	getR () const
	The value r. More...
long	getPPowR () const
	The value p^r. More...
void	restoreContext () const
	Restores the NTL context for p^r. More...
zzX	getMask_zzX (long i, long j) const

Detailed Description

The structure of Z[X]/(Phi_m(X), p)

An object of type PAlgebraMod stores information about a PAlgebra object zMStar, and an integer r. It also provides support for encoding and decoding plaintext slots.

the PAlgebra object zMStar defines (Z/mZ)^* /(0), and the PAlgebraMod object stores various tables related to the polynomial ring Z/(p^r)[X]. To do this most efficiently, if p == 2 and r == 1, then these polynomials are represented as GF2X's, and otherwise as zz_pX's. Thus, the types of these objects are not determined until run time. As such, we need to use a class hierarchy, as follows.

• PAlgebraModBase is a virtual class

• PAlgebraModDerived<type> is a derived template class, where type is either PA_GF2 or PA_zz_p.

• The class PAlgebraMod is a simple wrapper around a smart pointer to a PAlgebraModBase object: copying a PAlgebra object results is a "deep copy" of the underlying object of the derived class. It provides dDirect access to the virtual methods of PAlgebraModBase, along with a "downcast" operator to get a reference to the object as a derived type, and also == and != operators.

Constructor & Destructor Documentation

PAlgebraMod()

helib::PAlgebraMod::PAlgebraMod ( const PAlgebra &  zMStar, long  r  )

inlineexplicit

Member Function Documentation

getCx()

const PAlgebraModCx& helib::PAlgebraMod::getCx ( ) const

inline

getDerived()

template<typename type >

const PAlgebraModDerived<type>& helib::PAlgebraMod::getDerived ( type  ) const

inline

Downcast operator example: const PAlgebraModDerived<PA_GF2>& rep = alMod.getDerived(PA_GF2());

getFactorsOverZZ()

const std::vector<NTL::ZZX>& helib::PAlgebraMod::getFactorsOverZZ ( ) const

inline

Returns reference to the factorization of Phi_m(X) mod p^r, but as ZZX's.

getMask_zzX()

zzX helib::PAlgebraMod::getMask_zzX ( long  i, long  j  ) const

inline

getPPowR()

long helib::PAlgebraMod::getPPowR ( ) const

inline

The value p^r.

getR()

long helib::PAlgebraMod::getR ( ) const

inline

The value r.

getTag()

PA_tag helib::PAlgebraMod::getTag ( ) const

inline

Returns the type tag: PA_GF2_tag or PA_zz_p_tag.

getZMStar()

const PAlgebra& helib::PAlgebraMod::getZMStar ( ) const

inline

Returns reference to underlying PAlgebra object.

operator!=()

bool helib::PAlgebraMod::operator!= ( const PAlgebraMod &  other ) const

inline

operator==()

bool helib::PAlgebraMod::operator== ( const PAlgebraMod &  other ) const

inline

restoreContext()

void helib::PAlgebraMod::restoreContext ( ) const

inline

Restores the NTL context for p^r.