A Ctxt object holds a single ciphertext. More...

#include <Ctxt.h>

Public Member Functions
	Ctxt (const Ctxt &other)=default

	Ctxt (const PubKey &newPubKey, long newPtxtSpace=0)

	Ctxt (ZeroCtxtLike_type, const Ctxt &ctxt)

void	DummyEncrypt (const NTL::ZZX &ptxt, double size=-1.0)

Ctxt &	operator= (const Ctxt &other)

bool	operator== (const Ctxt &other) const

bool	operator!= (const Ctxt &other) const

bool	equalsTo (const Ctxt &other, bool comparePkeys=true) const

void	writeTo (std::ostream &str) const
	Write out the `Ctxt` object in binary format. More...

void	read (std::istream &str)
	In-place read from the stream the serialized `Ctxt` object in binary format. More...

void	writeToJSON (std::ostream &str) const
	Write out the ciphertext (`Ctxt`) object to the output stream using JSON format. More...

JsonWrapper	writeToJSON () const
	Write out the ciphertext (`Ctxt`) object to a `JsonWrapper`. More...

void	readJSON (std::istream &str)
	In-place read from the `str` `std::istream` the serialized ciphertext (`Ctxt`) object. More...

void	readJSON (const JsonWrapper &j)
	In-place read from the `JsonWrapper` the serialized ciphertext (`Ctxt`) object. More...

void	addedNoiseForCKKSDecryption (const SecKey &sk, double eps, NTL::ZZX &noise) const

Ciphertext maintenance
void	reducePtxtSpace (long newPtxtSpace)
	Reduce plaintext space to a divisor of the original plaintext space. More...

void	hackPtxtSpace (long newPtxtSpace)

void	bumpNoiseBound (double factor)

void	relin_CKKS_adjust ()

void	reLinearize (long keyIdx=0)

Ctxt &	cleanUp ()

void	blindCtxt (const NTL::ZZX &poly)
	Add a high-noise encryption of the given constant. More...

NTL::xdouble	modSwitchAddedNoiseBound () const
	Estimate the added noise. More...

void	modUpToSet (const IndexSet &s)
	Modulus-switching up (to a larger modulus). Must have primeSet <= s, and s must contain either all the special primes or none of them. More...

void	modDownToSet (const IndexSet &s)
	Modulus-switching down (to a smaller modulus). mod-switch down to primeSet \intersect s, after this call we have primeSet<=s. s must contain either all special primes or none of them. More...

void	bringToSet (const IndexSet &s)
	make the primeSet equal to newPrimeSet, via modUpToSet and modDownToSet More...

double	naturalSize () const

IndexSet	naturalPrimeSet () const
	"natural size" is size before squaring More...

void	dropSmallAndSpecialPrimes ()
	the corresponding primeSet More...

NTL::xdouble	totalNoiseBound () const
	returns the total noise bound, which for CKKS is ptxtMag*ratFactor + noiseBound More...

double	errorBound () const
	for CKKS, returns a bound on the absolute error (which is noiseBound/ratFactor); for BGV, returns 0. More...

double	capacity () const
	returns the "capacity" of a ciphertext, which is the log2 of the ratio of the modulus to the total noise bound More...

double	logOfPrimeSet () const
	returns the log of the prime set More...

long	bitCapacity () const
	the capacity in bits, returned as an integer More...

double	rawModSwitch (std::vector< NTL::ZZX > &zzParts, long toModulus) const
	Special-purpose modulus-switching for bootstrapping. More...

void	evalPoly (const NTL::ZZX &poly)
	compute the power X,X^2,...,X^n More...

Utility methods
void	clear ()

bool	isEmpty () const
	Is this an empty ciphertext without any parts. More...

bool	inCanonicalForm (long keyID=0) const
	A canonical ciphertext has (at most) handles pointing to (1,s) More...

bool	isCorrect () const
	Would this ciphertext be decrypted without errors? More...

const Context &	getContext () const

const PubKey &	getPubKey () const

const IndexSet &	getPrimeSet () const

long	getPtxtSpace () const

const NTL::xdouble &	getNoiseBound () const

const NTL::xdouble &	getRatFactor () const

const NTL::xdouble &	getPtxtMag () const

void	setPtxtMag (const NTL::xdouble &z)

long	getKeyID () const

bool	isCKKS () const

long	effectiveR () const

double	log_of_ratio () const
	Returns log(noiseBound) - log(q) More...

Static Public Member Functions
static Ctxt	readFrom (std::istream &str, const PubKey &pubKey)
	Read from the stream the serialized `Ctxt` object in binary format. More...

static Ctxt	readFromJSON (std::istream &str, const PubKey &pubKey)
	Read from the stream the serialized ciphertext (`Ctxt`) object using JSON format. More...

static Ctxt	readFromJSON (const JsonWrapper &j, const PubKey &pubKey)
	Read from the `JsonWrapper` the serialized ciphertext (`Ctxt`) object. More...

static void	equalizeRationalFactors (Ctxt &c1, Ctxt &c2)

Static Public Attributes
static constexpr std::string_view	typeName = "Ctxt"
	Class label to be added to JSON serialization as object type information. More...

Friends
class	PubKey

class	SecKey

class	BasicAutomorphPrecon

std::istream &	operator>> (std::istream &str, Ctxt &ctxt)

std::ostream &	operator<< (std::ostream &str, const Ctxt &ctxt)

Ciphertext arithmetic
void	negate ()

Ctxt &	operator+= (const Ctxt &other)

Ctxt &	operator-= (const Ctxt &other)

void	addCtxt (const Ctxt &other, bool negative=false)

void	multLowLvl (const Ctxt &other, bool destructive=false)

Ctxt &	operator*= (const Ctxt &other)

void	automorph (long k)

Ctxt &	operator>>= (long k)

void	complexConj ()

void	smartAutomorph (long k)
	automorphism with re-linearization More...

void	frobeniusAutomorph (long j)
	applies the automorphism p^j using smartAutomorphism More...

Ctxt &	operator*= (const NTL::ZZX &poly)
	Times equals operator with a `ZZX`. More...

void	addConstant (const DoubleCRT &dcrt, double size=-1.0)

void	addConstant (const NTL::ZZX &poly, double size=-1.0)

template<typename Scheme >
void	addConstant (const Ptxt< Scheme > &ptxt, bool neg=false)
	Add a plaintext to this `Ctxt`. More...

template<typename Scheme >
Ctxt &	operator+= (const Ptxt< Scheme > &ptxt)

template<typename Scheme >
Ctxt &	operator-= (const Ptxt< Scheme > &ptxt)

void	addConstantCKKS (std::pair< long, long >)
	add a rational number in the form a/b, a,b are long More...

void	addConstantCKKS (double x)

void	addConstantCKKS (const DoubleCRT &dcrt, NTL::xdouble size=NTL::xdouble(-1.0), NTL::xdouble factor=NTL::xdouble(-1.0))

void	addConstantCKKS (const NTL::ZZX &poly, NTL::xdouble size=NTL::xdouble(-1.0), NTL::xdouble factor=NTL::xdouble(-1.0))

void	addConstantCKKS (const std::vector< std::complex< double >> &ptxt)

void	addConstantCKKS (const Ptxt< CKKS > &ptxt)
	Add a `CKKS` plaintext to this `Ctxt`. More...

void	addConstantCKKS (const NTL::ZZ &c)

void	multByConstant (const DoubleCRT &dcrt, double size=-1.0)

void	multByConstant (const NTL::ZZX &poly, double size=-1.0)

void	multByConstant (const zzX &poly, double size=-1.0)

void	multByConstant (const PtxtArray &ptxt)
	Multiply a `Ctxt` with a specified plaintext constant. More...

void	multByConstant (const EncodedPtxt &ptxt)
	Multiply a `Ctxt` with a specified plaintext constant. More...

void	multByConstant (const FatEncodedPtxt &ptxt)
	Multiply a `Ctxt` with a specified plaintext constant. More...

void	multByConstant (const NTL::ZZ &ptxt)
	Multiply a `Ctxt` with an `NTL::ZZ` scalar. More...

void	multByConstant (long ptxt)
	Multiply a `Ctxt` with a `long` scalar. More...

void	multByConstant (double ptxt)
	Multiply a `Ctxt` with a `double` scalar. More...

void	multByConstant (NTL::xdouble ptxt)
	Multiply a `Ctxt` with an `NTL::xdouble` scalar. More...

Ctxt &	operator*= (const PtxtArray &ptxt)
	Times equals operator with a plaintext constant. More...

Ctxt &	operator*= (const EncodedPtxt &ptxt)
	Times equals operator with a plaintext constant. More...

Ctxt &	operator*= (const FatEncodedPtxt &ptxt)
	Times equals operator with a plaintext constant. More...

Ctxt &	operator*= (const NTL::ZZ &ptxt)
	Times equals operator with an `NTL::ZZ` scalar. More...

Ctxt &	operator*= (long ptxt)
	Times equals operator with a `long` scalar. More...

Ctxt &	operator*= (double ptxt)
	Times equals operator with a `double` scalar. More...

Ctxt &	operator*= (NTL::xdouble ptxt)
	Times equals operator with an `NTL::xdouble` scalar. More...

void	addConstant (const PtxtArray &ptxt, bool neg=false)
	Add to a `Ctxt` a specified plaintext constant. More...

void	addConstant (const EncodedPtxt &ptxt, bool neg=false)
	Add to a `Ctxt` a specified plaintext constant. More...

void	addConstant (const FatEncodedPtxt &ptxt, bool neg=false)
	Add to a `Ctxt` a specified plaintext constant. More...

void	addConstant (const NTL::ZZ &ptxt, bool neg=false)
	Add to a `Ctxt` an `NTL::ZZ` scalar. More...

void	addConstant (long ptxt, bool neg=false)
	Add to a `Ctxt` a `long` scalar. More...

void	addConstant (double ptxt, bool neg=false)
	Add to a `Ctxt` a `double` scalar. More...

void	addConstant (NTL::xdouble ptxt, bool neg=false)
	Add to a `Ctxt` an `NTL::xdouble` scalar. More...

Ctxt &	operator+= (const PtxtArray &ptxt)
	Plus equals operator with plaintext constant. More...

Ctxt &	operator+= (const EncodedPtxt &ptxt)
	Plus equals operator with plaintext constant. More...

Ctxt &	operator+= (const FatEncodedPtxt &ptxt)
	Plus equals operator with plaintext constant. More...

Ctxt &	operator+= (const NTL::ZZ &ptxt)
	Plus equals operator with an `NTL::ZZ` scalar. More...

Ctxt &	operator+= (long ptxt)
	Plus equals operator with a `long` scalar. More...

Ctxt &	operator+= (double ptxt)
	Plus equals operator with a `double` scalar. More...

Ctxt &	operator+= (NTL::xdouble ptxt)
	Plus equals operator with an `NTL::xdouble` scalar. More...

Ctxt &	operator-= (const PtxtArray &ptxt)
	Minus equals operator with plaintext constant. More...

Ctxt &	operator-= (const EncodedPtxt &ptxt)
	Minus equals operator with plaintext constant. More...

Ctxt &	operator-= (const FatEncodedPtxt &ptxt)
	Minus equals operator with plaintext constant. More...

Ctxt &	operator-= (const NTL::ZZ &ptxt)
	Minus equals operator with an `NTL::ZZ` scalar. More...

Ctxt &	operator-= (long ptxt)
	Minus equals operator with a `long` scalar. More...

Ctxt &	operator-= (double ptxt)
	Minus equals operator with a `double` scalar. More...

Ctxt &	operator-= (NTL::xdouble ptxt)
	Minus equals operator with an `NTL::xdouble` scalar. More...

template<typename Scheme >
void	multByConstant (const Ptxt< Scheme > &ptxt)
	Multiply a plaintext to this `Ctxt`. More...

template<typename Scheme >
Ctxt &	operator*= (const Ptxt< Scheme > &ptxt)

void	multByConstantCKKS (double x)
	multiply by a rational number or floating point More...

void	multByConstantCKKS (std::pair< long, long > num)

void	multByConstantCKKS (const DoubleCRT &dcrt, NTL::xdouble size=NTL::xdouble(-1.0), NTL::xdouble factor=NTL::xdouble(-1.0), double roundingErr=-1.0)

void	multByConstantCKKS (const NTL::ZZX &poly, NTL::xdouble size=NTL::xdouble(-1.0), NTL::xdouble factor=NTL::xdouble(-1.0), double roundingErr=-1.0)

void	multByConstantCKKS (const Ptxt< CKKS > &ptxt)
	Multiply a `CKKS` plaintext to this `Ctxt`. More...

void	multByConstantCKKS (const std::vector< std::complex< double >> &ptxt)

void	xorConstant (const DoubleCRT &poly, UNUSED double size=-1.0)

void	xorConstant (const NTL::ZZX &poly, double size=-1.0)

void	nxorConstant (const DoubleCRT &poly, UNUSED double size=-1.0)

void	nxorConstant (const NTL::ZZX &poly, double size=-1.0)

void	divideByP ()

void	multByP (long e=1)

void	divideBy2 ()

void	extractBits (std::vector< Ctxt > &bits, long nBits2extract=0)

void	multiplyBy (const Ctxt &other)

void	multiplyBy2 (const Ctxt &other1, const Ctxt &other2)

void	square ()

void	cube ()

void	power (long e)
	raise ciphertext to some power More...

Detailed Description

A Ctxt object holds a single ciphertext.

The class Ctxt includes a std::vector<CtxtPart>: For a Ctxt c, c[i] is the i'th ciphertext part, which can be used also as a DoubleCRT object (since CtxtPart is derived from DoubleCRT). By convention, c[0], the first CtxtPart object in the std::vector, has skHndl that points to 1 (i.e., it is just added in upon decryption, without being multiplied by anything). We maintain the invariance that all the parts of a ciphertext are defined relative to the same set of primes.

A ciphertext contains also pointers to the general parameters of this FHE instance and the public key, and a high-probability bound on the noise magnitude (kept in the noiseBound data member). The noise bound is a bound on the l-infinity norm of the canonical embedding of the noise polynomial, namely its evaluation in roots of the ring polynomial (which are the complex primitive roots of unity). The noise bound is added on addition, multiplied on multiplications, remains unchanged for automorphism, and is roughly scaled down by mod-switching with some added factor, and similarly scaled up by key-switching with some added factor.

Constructor & Destructor Documentation

◆ Ctxt() [1/3]

helib::Ctxt::Ctxt ( const Ctxt & other )

default

◆ Ctxt() [2/3]

helib::Ctxt::Ctxt	(	const PubKey &	newPubKey,
		long	newPtxtSpace = `0`
	)

explicit

◆ Ctxt() [3/3]

helib::Ctxt::Ctxt	(	ZeroCtxtLike_type	,
		const Ctxt &	ctxt
	)

Member Function Documentation

◆ addConstant() [1/10]

void helib::Ctxt::addConstant	(	const DoubleCRT &	dcrt,
		double	size = `-1.0`
	)

Add a constant polynomial. If provided, size should be a high-probability bound on the L-infty norm of the canonical embedding Otherwise, for the DoubleCRT variant, a bound based on the assumption that the coefficients are uniformly and independently distributed over [-ptxtSpace/2, ptxtSpace/2]. For the other variants, explicit bounds are computed (if not CKKS).

◆ addConstant() [2/10]

void helib::Ctxt::addConstant	(	const EncodedPtxt &	ptxt,
		bool	neg = `false`
	)

Add to a Ctxt a specified plaintext constant.

Parameters

ptxt	The constant to add as an `EncodedPtxt` object.
neg	Flag to specify if the constant is negative. Default is `false`.

Note: EncodedPtxt is a plaintext object containing NTL::ZZX data.

◆ addConstant() [3/10]

void helib::Ctxt::addConstant	(	const FatEncodedPtxt &	ptxt,
		bool	neg = `false`
	)

Add to a Ctxt a specified plaintext constant.

Parameters

ptxt	The constant to add as a `FatEncodedPtxt` object.
neg	Flag to specify if the constant is negative. Default is `false`.

Note: FatEncodedPtxt is a plaintext object containing helib::DoubleCRT data.

◆ addConstant() [4/10]

void helib::Ctxt::addConstant	(	const NTL::ZZ &	ptxt,
		bool	neg = `false`
	)

Add to a Ctxt an NTL::ZZ scalar.

Parameters

ptxt	The scalar to add.
neg	Flag to specify if the constant is negative. Default is `false`.

◆ addConstant() [5/10]

void helib::Ctxt::addConstant	(	const NTL::ZZX &	poly,
		double	size = `-1.0`
	)

◆ addConstant() [6/10]

template<typename Scheme >

void helib::Ctxt::addConstant	(	const Ptxt< Scheme > &	ptxt,
		bool	neg = `false`
	)

inline

Add a plaintext to this Ctxt.

Parameters

ptxt	Plaintext `Ptxt` object with which to add.

◆ addConstant() [7/10]

void helib::Ctxt::addConstant	(	const PtxtArray &	ptxt,
		bool	neg = `false`
	)

Add to a Ctxt a specified plaintext constant.

Parameters

ptxt	The constant to add as a `PtxtArray` object.
neg	Flag to specify if the constant is negative. Default is `false`.

◆ addConstant() [8/10]

void helib::Ctxt::addConstant	(	double	ptxt,
		bool	neg = `false`
	)

Add to a Ctxt a double scalar.

Parameters

ptxt	The scalar to add.
neg	Flag to specify if the constant is negative. Default is `false`.

◆ addConstant() [9/10]

void helib::Ctxt::addConstant	(	long	ptxt,
		bool	neg = `false`
	)

Add to a Ctxt a long scalar.

Parameters

ptxt	The scalar to add.
neg	Flag to specify if the constant is negative. Default is `false`.

◆ addConstant() [10/10]

void helib::Ctxt::addConstant	(	NTL::xdouble	ptxt,
		bool	neg = `false`
	)

Add to a Ctxt an NTL::xdouble scalar.

Parameters

ptxt	The scalar to add.
neg	Flag to specify if the constant is negative. Default is `false`.

◆ addConstantCKKS() [1/7]

void helib::Ctxt::addConstantCKKS	(	const DoubleCRT &	dcrt,
		NTL::xdouble	size = `NTL::xdouble(-1.0)`,
		NTL::xdouble	factor = `NTL::xdouble(-1.0)`
	)

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator+=(const FatEncodedPtxt& ptxt) instead.

◆ addConstantCKKS() [2/7]

void helib::Ctxt::addConstantCKKS ( const NTL::ZZ & c )

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator+=(const NTL::ZZ& ptxt) instead.

◆ addConstantCKKS() [3/7]

void helib::Ctxt::addConstantCKKS	(	const NTL::ZZX &	poly,
		NTL::xdouble	size = `NTL::xdouble(-1.0)`,
		NTL::xdouble	factor = `NTL::xdouble(-1.0)`
	)

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator+=(const EncodedPtxt& ptxt) instead.

◆ addConstantCKKS() [4/7]

void helib::Ctxt::addConstantCKKS ( const Ptxt< CKKS > & ptxt )

Add a CKKS plaintext to this Ctxt.

Parameters

ptxt	Plaintext `Ptxt` object with which to add.

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator+=(const PtxtArray& ptxt) instead.

◆ addConstantCKKS() [5/7]

void helib::Ctxt::addConstantCKKS ( const std::vector< std::complex< double >> & ptxt )

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator+=(const PtxtArray& ptxt) instead.

◆ addConstantCKKS() [6/7]

void helib::Ctxt::addConstantCKKS ( double x )

inline

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator+=(double ptxt) instead.

◆ addConstantCKKS() [7/7]

void helib::Ctxt::addConstantCKKS ( std::pair< long, long > num )

add a rational number in the form a/b, a,b are long

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator+=(double ptxt) instead.

◆ addCtxt()

void helib::Ctxt::addCtxt	(	const Ctxt &	other,
		bool	negative = `false`
	)

◆ addedNoiseForCKKSDecryption()

void helib::Ctxt::addedNoiseForCKKSDecryption	(	const SecKey &	sk,
		double	eps,
		NTL::ZZX &	noise
	)		const

◆ automorph()

void helib::Ctxt::automorph ( long k )

◆ bitCapacity()

long helib::Ctxt::bitCapacity ( ) const

inline

the capacity in bits, returned as an integer

◆ blindCtxt()

void helib::Ctxt::blindCtxt ( const NTL::ZZX & poly )

Add a high-noise encryption of the given constant.

◆ bringToSet()

void helib::Ctxt::bringToSet ( const IndexSet & s )

make the primeSet equal to newPrimeSet, via modUpToSet and modDownToSet

◆ bumpNoiseBound()

void helib::Ctxt::bumpNoiseBound ( double factor )

inline

◆ capacity()

double helib::Ctxt::capacity ( ) const

inline

returns the "capacity" of a ciphertext, which is the log2 of the ratio of the modulus to the total noise bound

◆ cleanUp()

Ctxt & helib::Ctxt::cleanUp ( )

◆ clear()

void helib::Ctxt::clear ( )

inline

◆ complexConj()

void helib::Ctxt::complexConj ( )

◆ cube()

void helib::Ctxt::cube ( )

inline

◆ divideBy2()

void helib::Ctxt::divideBy2 ( )

◆ divideByP()

void helib::Ctxt::divideByP ( )

Divide a ciphertext by p, for plaintext space p^r, r>1. It is assumed that the ciphertext encrypts a polynomial which is zero mod p. If this is not the case then the result will not be a valid ciphertext anymore. As a side-effect, the plaintext space is reduced from p^r to p^{r-1}.

◆ dropSmallAndSpecialPrimes()

void helib::Ctxt::dropSmallAndSpecialPrimes ( )

the corresponding primeSet

drop all smallPrimes and specialPrimes, adding ctxtPrimes as necessary to ensure that the scaled noise is above the modulus-switching added noise term.

◆ DummyEncrypt()

void helib::Ctxt::DummyEncrypt	(	const NTL::ZZX &	ptxt,
		double	size = `-1.0`
	)

Dummy encryption, just encodes the plaintext in a Ctxt object If provided, size should be a high-probability bound on the L-infty norm of the canonical embedding

◆ effectiveR()

long helib::Ctxt::effectiveR ( ) const

inline

◆ equalizeRationalFactors()

void helib::Ctxt::equalizeRationalFactors	(	Ctxt &	c1,
		Ctxt &	c2
	)

static

◆ equalsTo()

bool helib::Ctxt::equalsTo	(	const Ctxt &	other,
		bool	comparePkeys = `true`
	)		const

◆ errorBound()

double helib::Ctxt::errorBound ( ) const

inline

for CKKS, returns a bound on the absolute error (which is noiseBound/ratFactor); for BGV, returns 0.

◆ evalPoly()

void helib::Ctxt::evalPoly ( const NTL::ZZX & poly )

compute the power X,X^2,...,X^n

Evaluate the cleartext poly on the encrypted ciphertext

◆ extractBits()

void helib::Ctxt::extractBits	(	std::vector< Ctxt > &	bits,
		long	nBits2extract = `0`
	)

inline

◆ frobeniusAutomorph()

void helib::Ctxt::frobeniusAutomorph ( long j )

applies the automorphism p^j using smartAutomorphism

◆ getContext()

const Context& helib::Ctxt::getContext ( ) const

inline

◆ getKeyID()

long helib::Ctxt::getKeyID ( ) const

◆ getNoiseBound()

const NTL::xdouble& helib::Ctxt::getNoiseBound ( ) const

inline

◆ getPrimeSet()

const IndexSet& helib::Ctxt::getPrimeSet ( ) const

inline

◆ getPtxtMag()

const NTL::xdouble& helib::Ctxt::getPtxtMag ( ) const

inline

◆ getPtxtSpace()

long helib::Ctxt::getPtxtSpace ( ) const

inline

◆ getPubKey()

const PubKey& helib::Ctxt::getPubKey ( ) const

inline

◆ getRatFactor()

const NTL::xdouble& helib::Ctxt::getRatFactor ( ) const

inline

◆ hackPtxtSpace()

void helib::Ctxt::hackPtxtSpace ( long newPtxtSpace )

inline

◆ inCanonicalForm()

bool helib::Ctxt::inCanonicalForm ( long keyID = 0 ) const

inline

A canonical ciphertext has (at most) handles pointing to (1,s)

◆ isCKKS()

bool helib::Ctxt::isCKKS ( ) const

inline

◆ isCorrect()

bool helib::Ctxt::isCorrect ( ) const

Would this ciphertext be decrypted without errors?

◆ isEmpty()

bool helib::Ctxt::isEmpty ( ) const

inline

Is this an empty ciphertext without any parts.

◆ log_of_ratio()

double helib::Ctxt::log_of_ratio ( ) const

inline

Returns log(noiseBound) - log(q)

Deprecated:: This is deprecated. Please use Ctxt::capacity() instead.

◆ logOfPrimeSet()

double helib::Ctxt::logOfPrimeSet ( ) const

inline

returns the log of the prime set

◆ modDownToSet()

void helib::Ctxt::modDownToSet ( const IndexSet & s )

Modulus-switching down (to a smaller modulus). mod-switch down to primeSet \intersect s, after this call we have primeSet<=s. s must contain either all special primes or none of them.

◆ modSwitchAddedNoiseBound()

NTL::xdouble helib::Ctxt::modSwitchAddedNoiseBound ( ) const

Estimate the added noise.

◆ modUpToSet()

void helib::Ctxt::modUpToSet ( const IndexSet & s )

Modulus-switching up (to a larger modulus). Must have primeSet <= s, and s must contain either all the special primes or none of them.

◆ multByConstant() [1/11]

void helib::Ctxt::multByConstant	(	const DoubleCRT &	dcrt,
		double	size = `-1.0`
	)

Multiply-by-constant. If the size is not given, for the DCRT variant, we use a high probability bound assuming "random" coefficients mod ptxtSpace, while for the other variants, we use explicitly computed bounds (if not CKKS).

◆ multByConstant() [2/11]

void helib::Ctxt::multByConstant ( const EncodedPtxt & ptxt )

Multiply a Ctxt with a specified plaintext constant.

Parameters

ptxt	The constant to multiply as an `EncodedPtxt` object.

Note: EncodedPtxt is a plaintext object containing NTL::ZZX data.

◆ multByConstant() [3/11]

void helib::Ctxt::multByConstant ( const FatEncodedPtxt & ptxt )

Multiply a Ctxt with a specified plaintext constant.

Parameters

ptxt	The constant to multiply as a `FatEncodedPtxt` object.

Note: FatEncodedPtxt is a plaintext object containing helib::DoubleCRT data.

◆ multByConstant() [4/11]

void helib::Ctxt::multByConstant ( const NTL::ZZ & ptxt )

Multiply a Ctxt with an NTL::ZZ scalar.

Parameters

ptxt	Scalar to multiply.

◆ multByConstant() [5/11]

void helib::Ctxt::multByConstant	(	const NTL::ZZX &	poly,
		double	size = `-1.0`
	)

◆ multByConstant() [6/11]

template<typename Scheme >

void helib::Ctxt::multByConstant ( const Ptxt< Scheme > & ptxt )

inline

Multiply a plaintext to this Ctxt.

Parameters

ptxt	Plaintext `Ptxt` object with which to multiply.

◆ multByConstant() [7/11]

void helib::Ctxt::multByConstant ( const PtxtArray & ptxt )

Multiply a Ctxt with a specified plaintext constant.

Parameters

ptxt	The constant to multiply as a `PtxtArray` object.

◆ multByConstant() [8/11]

void helib::Ctxt::multByConstant	(	const zzX &	poly,
		double	size = `-1.0`
	)

◆ multByConstant() [9/11]

void helib::Ctxt::multByConstant ( double ptxt )

Multiply a Ctxt with a double scalar.

Parameters

ptxt	Scalar to multiply.

◆ multByConstant() [10/11]

void helib::Ctxt::multByConstant ( long ptxt )

Multiply a Ctxt with a long scalar.

Parameters

ptxt	Scalar to multiply.

◆ multByConstant() [11/11]

void helib::Ctxt::multByConstant ( NTL::xdouble ptxt )

Multiply a Ctxt with an NTL::xdouble scalar.

Parameters

ptxt	Scalar to multiply.

◆ multByConstantCKKS() [1/6]

void helib::Ctxt::multByConstantCKKS	(	const DoubleCRT &	dcrt,
		NTL::xdouble	size = `NTL::xdouble(-1.0)`,
		NTL::xdouble	factor = `NTL::xdouble(-1.0)`,
		double	roundingErr = `-1.0`
	)

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator*=(const FatEncodedPtxt& ptxt) instead.

◆ multByConstantCKKS() [2/6]

void helib::Ctxt::multByConstantCKKS	(	const NTL::ZZX &	poly,
		NTL::xdouble	size = `NTL::xdouble(-1.0)`,
		NTL::xdouble	factor = `NTL::xdouble(-1.0)`,
		double	roundingErr = `-1.0`
	)

inline

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator*=(const EncodedPtxt& ptxt) instead.

◆ multByConstantCKKS() [3/6]

void helib::Ctxt::multByConstantCKKS ( const Ptxt< CKKS > & ptxt )

Multiply a CKKS plaintext to this Ctxt.

Parameters

ptxt	Plaintext `Ptxt` object polynomial with which to multiply.

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator*=(const PtxtArray& ptxt) instead.

◆ multByConstantCKKS() [4/6]

void helib::Ctxt::multByConstantCKKS ( const std::vector< std::complex< double >> & ptxt )

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator*=(const PtxtArray& ptxt) instead.

◆ multByConstantCKKS() [5/6]

void helib::Ctxt::multByConstantCKKS ( double x )

inline

multiply by a rational number or floating point

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator*=(double ptxt) instead.

◆ multByConstantCKKS() [6/6]

void helib::Ctxt::multByConstantCKKS ( std::pair< long, long > num )

inline

Deprecated:: This function is deprecated in favor of a newer API. Please use Ctxt::operator*=(double ptxt) instead.

◆ multByP()

void helib::Ctxt::multByP ( long e = 1 )

inline

Multiply ciphertext by p^e, for plaintext space p^r. This also has the side-effect of increasing the plaintext space to p^{r+e}.

◆ multiplyBy()

void helib::Ctxt::multiplyBy ( const Ctxt & other )

◆ multiplyBy2()

void helib::Ctxt::multiplyBy2	(	const Ctxt &	other1,
		const Ctxt &	other2
	)

◆ multLowLvl()

void helib::Ctxt::multLowLvl	(	const Ctxt &	other,
		bool	destructive = `false`
	)

◆ naturalPrimeSet()

IndexSet helib::Ctxt::naturalPrimeSet ( ) const

"natural size" is size before squaring

◆ naturalSize()

double helib::Ctxt::naturalSize ( ) const

◆ negate()

void helib::Ctxt::negate ( )

◆ nxorConstant() [1/2]

void helib::Ctxt::nxorConstant	(	const DoubleCRT &	poly,
		UNUSED double	size = `-1.0`
	)

inline

◆ nxorConstant() [2/2]

void helib::Ctxt::nxorConstant	(	const NTL::ZZX &	poly,
		double	size = `-1.0`
	)

inline

◆ operator!=()

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

inline

◆ operator*=() [1/10]

Ctxt& helib::Ctxt::operator*= ( const Ctxt & other )

inline

◆ operator*=() [2/10]

Ctxt& helib::Ctxt::operator*= ( const EncodedPtxt & ptxt )

inline

Times equals operator with a plaintext constant.

Parameters

ptxt	Right hand side of multiplication.

Returns: Reference to *this post multiplication.

Note: EncodedPtxt is a plaintext object containing NTL::ZZX data.

◆ operator*=() [3/10]

Ctxt& helib::Ctxt::operator*= ( const FatEncodedPtxt & ptxt )

inline

Times equals operator with a plaintext constant.

Parameters

ptxt	Right hand side of multiplication.

Returns: Reference to *this post multiplication.

Note: FatEncodedPtxt is a plaintext object containing helib::DoubleCRT data.

◆ operator*=() [4/10]

Ctxt& helib::Ctxt::operator*= ( const NTL::ZZ & ptxt )

inline

Times equals operator with an NTL::ZZ scalar.

Parameters

ptxt	Right hand side of multiplication.

Returns: Reference to *this post multiplication.

◆ operator*=() [5/10]

Ctxt & helib::Ctxt::operator*= ( const NTL::ZZX & poly )

Times equals operator with a ZZX.

Parameters

poly	Element by which to multiply.

Returns: Reference to *this post multiplication.

Deprecated:: This function is deprecated in favor of a new EncodedPtxt-based API.
Please use Ctxt::operator*=(const EncodedPtxt& ptxt) instead.

◆ operator*=() [6/10]

template<typename Scheme >

Ctxt& helib::Ctxt::operator*= ( const Ptxt< Scheme > & ptxt )

inline

◆ operator*=() [7/10]

Ctxt& helib::Ctxt::operator*= ( const PtxtArray & ptxt )

inline

Times equals operator with a plaintext constant.

Parameters

ptxt	Right hand side of multiplication.

Returns: Reference to *this post multiplication.

◆ operator*=() [8/10]

Ctxt& helib::Ctxt::operator*= ( double ptxt )

inline

Times equals operator with a double scalar.

Parameters

ptxt	Right hand side of multiplication.

Returns: Reference to *this post multiplication.

◆ operator*=() [9/10]

Ctxt& helib::Ctxt::operator*= ( long ptxt )

inline

Times equals operator with a long scalar.

Parameters

ptxt	Right hand side of multiplication.

Returns: Reference to *this post multiplication.

◆ operator*=() [10/10]

Ctxt& helib::Ctxt::operator*= ( NTL::xdouble ptxt )

inline

Times equals operator with an NTL::xdouble scalar.

Parameters

ptxt	Right hand side of multiplication.

Returns: Reference to *this post multiplication.

◆ operator+=() [1/9]

Ctxt& helib::Ctxt::operator+= ( const Ctxt & other )

inline

◆ operator+=() [2/9]

Ctxt& helib::Ctxt::operator+= ( const EncodedPtxt & ptxt )

inline

Plus equals operator with plaintext constant.

Parameters

ptxt	Right hand side of addition.

Returns: Reference to *this post addition.

Note: EncodedPtxt is a plaintext object containing NTL::ZZX data.

◆ operator+=() [3/9]

Ctxt& helib::Ctxt::operator+= ( const FatEncodedPtxt & ptxt )

inline

Plus equals operator with plaintext constant.

Parameters

ptxt	Right hand side of addition.

Returns: Reference to *this post addition.

Note: FatEncodedPtxt is a plaintext object containing helib::DoubleCRT data.

◆ operator+=() [4/9]

Ctxt& helib::Ctxt::operator+= ( const NTL::ZZ & ptxt )

inline

Plus equals operator with an NTL::ZZ scalar.

Parameters

ptxt	Right hand side of addition.

Returns: Reference to *this post addition.

◆ operator+=() [5/9]

template<typename Scheme >

Ctxt& helib::Ctxt::operator+= ( const Ptxt< Scheme > & ptxt )

inline

◆ operator+=() [6/9]

Ctxt& helib::Ctxt::operator+= ( const PtxtArray & ptxt )

inline

Plus equals operator with plaintext constant.

Parameters

ptxt	Right hand side of addition.

Returns: Reference to *this post addition.

◆ operator+=() [7/9]

Ctxt& helib::Ctxt::operator+= ( double ptxt )

inline

Plus equals operator with a double scalar.

Parameters

ptxt	Right hand side of addition.

Returns: Reference to *this post addition.

◆ operator+=() [8/9]

Ctxt& helib::Ctxt::operator+= ( long ptxt )

inline

Plus equals operator with a long scalar.

Parameters

ptxt	Right hand side of addition.

Returns: Reference to *this post addition.

◆ operator+=() [9/9]

Ctxt& helib::Ctxt::operator+= ( NTL::xdouble ptxt )

inline

Plus equals operator with an NTL::xdouble scalar.

Parameters

ptxt	Right hand side of addition.

Returns: Reference to *this post addition.

◆ operator-=() [1/9]

Ctxt& helib::Ctxt::operator-= ( const Ctxt & other )

inline

◆ operator-=() [2/9]

Ctxt& helib::Ctxt::operator-= ( const EncodedPtxt & ptxt )

inline

Minus equals operator with plaintext constant.

Parameters

ptxt	Right hand side of subtraction.

Returns: Reference to *this post subtraction.

Note: EncodedPtxt is a plaintext object containing NTL::ZZX data.

◆ operator-=() [3/9]

Ctxt& helib::Ctxt::operator-= ( const FatEncodedPtxt & ptxt )

inline

Minus equals operator with plaintext constant.

Parameters

ptxt	Right hand side of subtraction.

Returns: Reference to *this post subtraction.

Note: FatEncodedPtxt is a plaintext object containing helib::DoubleCRT data.

◆ operator-=() [4/9]

Ctxt& helib::Ctxt::operator-= ( const NTL::ZZ & ptxt )

inline

Minus equals operator with an NTL::ZZ scalar.

Parameters

ptxt	Right hand side of subtraction.

Returns: Reference to *this post subtraction.

◆ operator-=() [5/9]

template<typename Scheme >

Ctxt& helib::Ctxt::operator-= ( const Ptxt< Scheme > & ptxt )

inline

◆ operator-=() [6/9]

Ctxt& helib::Ctxt::operator-= ( const PtxtArray & ptxt )

inline

Minus equals operator with plaintext constant.

Parameters

ptxt	Right hand side of subtraction.

Returns: Reference to *this post subtraction.

◆ operator-=() [7/9]

Ctxt& helib::Ctxt::operator-= ( double ptxt )

inline

Minus equals operator with a double scalar.

Parameters

ptxt	Right hand side of subtraction.

Returns: Reference to *this post subtraction.

◆ operator-=() [8/9]

Ctxt& helib::Ctxt::operator-= ( long ptxt )

inline

Minus equals operator with a long scalar.

Parameters

ptxt	Right hand side of subtraction.

Returns: Reference to *this post subtraction.

◆ operator-=() [9/9]

Ctxt& helib::Ctxt::operator-= ( NTL::xdouble ptxt )

inline

Minus equals operator with an NTL::xdouble scalar.

Parameters

ptxt	Right hand side of subtraction.

Returns: Reference to *this post subtraction.

◆ operator=()

Ctxt& helib::Ctxt::operator= ( const Ctxt & other )

inline

◆ operator==()

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

inline

◆ operator>>=()

Ctxt& helib::Ctxt::operator>>= ( long k )

inline

◆ power()

void helib::Ctxt::power ( long e )

raise ciphertext to some power

◆ rawModSwitch()

double helib::Ctxt::rawModSwitch	(	std::vector< NTL::ZZX > &	zzParts,
		long	toModulus
	)		const

Special-purpose modulus-switching for bootstrapping.

Mod-switch to an externally-supplied modulus. The modulus need not be in the moduli-chain in the context, and does not even need to be a prime. The ciphertext *this is not affected, instead the result is returned in the zzParts std::vector, as a std::vector of ZZX'es. Returns an estimate for the scaled noise (not including the additive mod switching noise)

◆ read()

void helib::Ctxt::read ( std::istream & str )

In-place read from the stream the serialized Ctxt object in binary format.

Parameters

str	Input `std::istream`.

◆ readFrom()

Ctxt helib::Ctxt::readFrom	(	std::istream &	str,
		const PubKey &	pubKey
	)

static

Read from the stream the serialized Ctxt object in binary format.

Parameters

str	Input `std::istream`.

Returns: The deserialized Ctxt object.

◆ readFromJSON() [1/2]

Ctxt helib::Ctxt::readFromJSON	(	const JsonWrapper &	j,
		const PubKey &	pubKey
	)

static

Read from the JsonWrapper the serialized ciphertext (Ctxt) object.

Parameters

j	The `JsonWrapper` containing the serialized `Ctxt` object.
pubKey	The `PubKey` to be used.

Returns: The deserialized Ctxt object.

◆ readFromJSON() [2/2]

Ctxt helib::Ctxt::readFromJSON	(	std::istream &	str,
		const PubKey &	pubKey
	)

static

Read from the stream the serialized ciphertext (Ctxt) object using JSON format.

Parameters

str	Input `std::istream`.
pubKey	The `PubKey` to be used.

Returns: The deserialized Ctxt object.

◆ readJSON() [1/2]

void helib::Ctxt::readJSON ( const JsonWrapper & j )

In-place read from the JsonWrapper the serialized ciphertext (Ctxt) object.

Parameters

j	The `JsonWrapper` containing the serialized `Ctxt` object.

◆ readJSON() [2/2]

void helib::Ctxt::readJSON ( std::istream & str )

In-place read from the str std::istream the serialized ciphertext (Ctxt) object.

Parameters

j	The `JsonWrapper` containing the serialized `Ctxt` object.

◆ reducePtxtSpace()

void helib::Ctxt::reducePtxtSpace ( long newPtxtSpace )

Reduce plaintext space to a divisor of the original plaintext space.

◆ relin_CKKS_adjust()

void helib::Ctxt::relin_CKKS_adjust ( )

◆ reLinearize()

void helib::Ctxt::reLinearize ( long keyIdx = 0 )

◆ setPtxtMag()

void helib::Ctxt::setPtxtMag ( const NTL::xdouble & z )

inline

◆ smartAutomorph()

void helib::Ctxt::smartAutomorph ( long k )

automorphism with re-linearization

◆ square()

void helib::Ctxt::square ( )

inline

◆ totalNoiseBound()

NTL::xdouble helib::Ctxt::totalNoiseBound ( ) const

inline

returns the total noise bound, which for CKKS is ptxtMag*ratFactor + noiseBound

◆ writeTo()

void helib::Ctxt::writeTo ( std::ostream & str ) const

Write out the Ctxt object in binary format.

Parameters

str	Output `std::ostream`.

◆ writeToJSON() [1/2]

JsonWrapper helib::Ctxt::writeToJSON ( ) const

Write out the ciphertext (Ctxt) object to a JsonWrapper.

Returns: The JsonWrapper.

◆ writeToJSON() [2/2]

void helib::Ctxt::writeToJSON ( std::ostream & str ) const

Write out the ciphertext (Ctxt) object to the output stream using JSON format.

Parameters

str	Output `std::ostream`.

◆ xorConstant() [1/2]

void helib::Ctxt::xorConstant	(	const DoubleCRT &	poly,
		UNUSED double	size = `-1.0`
	)

inline

Convenience method: XOR and nXOR with arbitrary plaintext space: a xor b = a+b-2ab = a + (1-2a)*b, a nxor b = 1-a-b+2ab = (b-1)(2a-1)+a

◆ xorConstant() [2/2]

void helib::Ctxt::xorConstant	(	const NTL::ZZX &	poly,
		double	size = `-1.0`
	)

inline

Friends And Related Function Documentation

◆ BasicAutomorphPrecon

friend class BasicAutomorphPrecon

friend

◆ operator<<

std::ostream& operator<<	(	std::ostream &	str,
		const Ctxt &	ctxt
	)

friend

◆ operator>>

std::istream& operator>>	(	std::istream &	str,
		Ctxt &	ctxt
	)

friend

◆ PubKey

friend class PubKey

friend

◆ SecKey

friend class SecKey

friend

Member Data Documentation

◆ typeName

constexpr std::string_view helib::Ctxt::typeName = "Ctxt"

staticconstexpr

Class label to be added to JSON serialization as object type information.

Public Member Functions

Static Public Member Functions

Static Public Attributes

Friends

Ciphertext arithmetic

Detailed Description

Constructor & Destructor Documentation

◆ Ctxt() [1/3]

◆ Ctxt() [2/3]

◆ Ctxt() [3/3]

Member Function Documentation

◆ addConstant() [1/10]

◆ addConstant() [2/10]

◆ addConstant() [3/10]

◆ addConstant() [4/10]

◆ addConstant() [5/10]

◆ addConstant() [6/10]

◆ addConstant() [7/10]

◆ addConstant() [8/10]

◆ addConstant() [9/10]

◆ addConstant() [10/10]

◆ addConstantCKKS() [1/7]

◆ addConstantCKKS() [2/7]

◆ addConstantCKKS() [3/7]

◆ addConstantCKKS() [4/7]

◆ addConstantCKKS() [5/7]

◆ addConstantCKKS() [6/7]

◆ addConstantCKKS() [7/7]

◆ addCtxt()

◆ addedNoiseForCKKSDecryption()

◆ automorph()

◆ bitCapacity()

◆ blindCtxt()

◆ bringToSet()

◆ bumpNoiseBound()

◆ capacity()

◆ cleanUp()

◆ clear()

◆ complexConj()

◆ cube()

◆ divideBy2()

◆ divideByP()

◆ dropSmallAndSpecialPrimes()

◆ DummyEncrypt()

◆ effectiveR()

◆ equalizeRationalFactors()

◆ equalsTo()

◆ errorBound()

◆ evalPoly()

◆ extractBits()

◆ frobeniusAutomorph()

◆ getContext()

◆ getKeyID()

◆ getNoiseBound()

◆ getPrimeSet()

◆ getPtxtMag()

◆ getPtxtSpace()

◆ getPubKey()

◆ getRatFactor()

◆ hackPtxtSpace()

◆ inCanonicalForm()

◆ isCKKS()

◆ isCorrect()

◆ isEmpty()

◆ log_of_ratio()

◆ logOfPrimeSet()

◆ modDownToSet()

◆ modSwitchAddedNoiseBound()

◆ modUpToSet()

◆ multByConstant() [1/11]

◆ multByConstant() [2/11]

◆ multByConstant() [3/11]

◆ multByConstant() [4/11]

◆ multByConstant() [5/11]

◆ multByConstant() [6/11]

◆ multByConstant() [7/11]

◆ multByConstant() [8/11]

◆ multByConstant() [9/11]

◆ multByConstant() [10/11]

◆ multByConstant() [11/11]