Gudhi::persistence_matrix::FieldOperators Class Reference

Concept of the field operator classes needed for the class Matrix. More...

Public Types
using	element_type = unspecified
using	characteristic_type = unspecified

Public Member Functions
	FieldOperators (characteristic_type characteristic=0)
	Default constructor. If a non-zero characteristic is given, initializes the field with it. The characteristic can later be changed again or initialized with set_characteristic. More...
void	set_characteristic (const characteristic_type &characteristic)
	Sets the characteristic of the field. Can eventually be omitted if the characteristic of the class is fixed. More...
const characteristic_type &	get_characteristic () const
	Returns the current characteristic. More...
template<typename Integer_type >
element_type	get_value (Integer_type e) const
	Returns the value of an integer in the field. That is the positive value of the integer modulo the current characteristic. More...
void	add_inplace (element_type &e1, const element_type &e2) const
	Stores in the first element the sum of two given elements in the field, that is (e1 + e2) % characteristic, such that the result is positive. More...
void	multiply_inplace (element_type &e1, const element_type &e2) const
	Stores in the first element the multiplication of two given elements in the field, that is (e1 * e2) % characteristic, such that the result is positive. More...
void	multiply_and_add_inplace_front (element_type &e, const element_type &m, const element_type &a) const
	Multiplies the first element with the second one and adds the third one, that is (e * m + a) % characteristic, such that the result is positive. Stores the result in the first element. More...
void	multiply_and_add_inplace_back (const element_type &e, const element_type &m, element_type &a) const
	Multiplies the first element with the second one and adds the third one, that is (e * m + a) % characteristic, such that the result is positive. Stores the result in the third element. More...
element_type	get_inverse (const element_type &e) const
	Returns the inverse of the given element in the field. More...
FieldOperators &	operator= (FieldOperators other)
	Assign operator.

Static Public Member Functions
static const element_type &	get_additive_identity ()
	Returns the additive identity of the field. More...
static const element_type &	get_multiplicative_identity ()
	Returns the multiplicative identity of the field. More...

Friends
void	swap (FieldOperators &f1, FieldOperators &f2)
	Swap operator.

Detailed Description

Concept of the field operator classes needed for the class Matrix.

Implementations of this concept are Gudhi::persistence_fields::Zp_field_operators, Gudhi::persistence_fields::Z2_field_operators, Gudhi::persistence_fields::Multi_field_operators and Gudhi::persistence_fields::Multi_field_operators_with_small_characteristics.

Member Typedef Documentation

characteristic_type

using Gudhi::persistence_matrix::FieldOperators::characteristic_type = unspecified

Type for the field characteristic.

element_type

using Gudhi::persistence_matrix::FieldOperators::element_type = unspecified

Type for the elements in the field.

Constructor & Destructor Documentation

FieldOperators()

Gudhi::persistence_matrix::FieldOperators::FieldOperators

(

characteristic_type

characteristic = 0

)

Default constructor. If a non-zero characteristic is given, initializes the field with it. The characteristic can later be changed again or initialized with set_characteristic.

Parameters

characteristic

Prime number corresponding to the desired characteristic of the field.

Member Function Documentation

add_inplace()

void Gudhi::persistence_matrix::FieldOperators::add_inplace	(	element_type &	e1,
		const element_type &	e2
	)		const

Stores in the first element the sum of two given elements in the field, that is (e1 + e2) % characteristic, such that the result is positive.

Parameters

e1	First element.
e2	Second element.

get_additive_identity()

static const element_type& Gudhi::persistence_matrix::FieldOperators::get_additive_identity ( )

static

Returns the additive identity of the field.

Returns

The additive identity of the field.

get_characteristic()

const characteristic_type& Gudhi::persistence_matrix::FieldOperators::get_characteristic

(

)

const

Returns the current characteristic.

Returns

The value of the current characteristic.

get_inverse()

element_type Gudhi::persistence_matrix::FieldOperators::get_inverse

(

const element_type &

e

)

const

Returns the inverse of the given element in the field.

Parameters

e	Element to get the inverse from.

Returns

Inverse in the current field of e % characteristic.

get_multiplicative_identity()

static const element_type& Gudhi::persistence_matrix::FieldOperators::get_multiplicative_identity ( )

static

Returns the multiplicative identity of the field.

Returns

The multiplicative identity of the field.

get_value()

template<typename Integer_type >

element_type Gudhi::persistence_matrix::FieldOperators::get_value

(

Integer_type

e

)

const

Returns the value of an integer in the field. That is the positive value of the integer modulo the current characteristic.

Template Parameters

Integer_type

A native integer type: int, unsigned int, long int, bool, etc.

Parameters

e	Integer to return the value from.

Returns

e modulo the current characteristic, such that the result is positive.

multiply_and_add_inplace_back()

void Gudhi::persistence_matrix::FieldOperators::multiply_and_add_inplace_back	(	const element_type &	e,
		const element_type &	m,
		element_type &	a
	)		const

Multiplies the first element with the second one and adds the third one, that is (e * m + a) % characteristic, such that the result is positive. Stores the result in the third element.

Parameters

e	First element.
m	Second element.
a	Third element.

multiply_and_add_inplace_front()

void Gudhi::persistence_matrix::FieldOperators::multiply_and_add_inplace_front	(	element_type &	e,
		const element_type &	m,
		const element_type &	a
	)		const

Multiplies the first element with the second one and adds the third one, that is (e * m + a) % characteristic, such that the result is positive. Stores the result in the first element.

Parameters

e	First element.
m	Second element.
a	Third element.

multiply_inplace()

void Gudhi::persistence_matrix::FieldOperators::multiply_inplace	(	element_type &	e1,
		const element_type &	e2
	)		const

Stores in the first element the multiplication of two given elements in the field, that is (e1 * e2) % characteristic, such that the result is positive.

Parameters

e1	First element.
e2	Second element.

set_characteristic()

void Gudhi::persistence_matrix::FieldOperators::set_characteristic

(

const characteristic_type &

characteristic

)

Sets the characteristic of the field. Can eventually be omitted if the characteristic of the class is fixed.

Parameters

characteristic

Prime number corresponding to the desired characteristic of the field.

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The documentation for this class was generated from the following file:

• concept/Persistence_matrix/FieldOperators.h