Polynomials::Monomial< number > Class Template Reference

#include <deal.II/base/polynomial.h>

Inheritance diagram for Polynomials::Monomial< number >:

Public Member Functions
	Monomial (const unsigned int n, const double coefficient=1.)
number	value (const number x) const
void	value (const number x, std::vector< number > &values) const
template<typename Number2 >
void	value (const Number2 x, const unsigned int n_derivatives, Number2 *values) const
template<std::size_t n_entries, typename Number2 >
void	values_of_array (const std::array< Number2, n_entries > &points, const unsigned int n_derivatives, std::array< Number2, n_entries > *values) const
unsigned int	degree () const
void	scale (const number factor)
template<typename number2 >
void	shift (const number2 offset)
Polynomial< number >	derivative () const
Polynomial< number >	primitive () const
Polynomial< number > &	operator*= (const double s)
Polynomial< number > &	operator*= (const Polynomial< number > &p)
Polynomial< number > &	operator+= (const Polynomial< number > &p)
Polynomial< number > &	operator-= (const Polynomial< number > &p)
bool	operator== (const Polynomial< number > &p) const
void	print (std::ostream &out) const
template<class Archive >
void	serialize (Archive &ar, const unsigned int version)
virtual std::size_t	memory_consumption () const
Subscriptor functionality
Classes derived from Subscriptor provide a facility to subscribe to this object. This is mostly used by the SmartPointer class.
void	subscribe (std::atomic< bool > *const validity, const std::string &identifier="") const
void	unsubscribe (std::atomic< bool > *const validity, const std::string &identifier="") const
unsigned int	n_subscriptions () const
template<typename StreamType >
void	list_subscribers (StreamType &stream) const
void	list_subscribers () const

Static Public Member Functions
static std::vector< Polynomial< number > >	generate_complete_basis (const unsigned int degree)
static ::ExceptionBase &	ExcInUse (int arg1, std::string arg2, std::string arg3)
static ::ExceptionBase &	ExcNoSubscriber (std::string arg1, std::string arg2)

Protected Member Functions
void	transform_into_standard_form ()

Static Protected Member Functions
static void	scale (std::vector< number > &coefficients, const number factor)
template<typename number2 >
static void	shift (std::vector< number > &coefficients, const number2 shift)
static void	multiply (std::vector< number > &coefficients, const number factor)

Protected Attributes
std::vector< number >	coefficients
bool	in_lagrange_product_form
std::vector< number >	lagrange_support_points
number	lagrange_weight

Private Types
using	map_value_type = decltype(counter_map)::value_type
using	map_iterator = decltype(counter_map)::iterator

Private Member Functions
void	check_no_subscribers () const noexcept

Static Private Member Functions
static std::vector< number >	make_vector (unsigned int n, const double coefficient)

Private Attributes
std::atomic< unsigned int >	counter
std::map< std::string, unsigned int >	counter_map
std::vector< std::atomic< bool > * >	validity_pointers
const std::type_info *	object_info

Static Private Attributes
static std::mutex	mutex

Detailed Description

template<typename number>
class Polynomials::Monomial< number >

Class generates Polynomial objects representing a monomial of degree n, that is, the function \(x^n\).

Definition at line 332 of file polynomial.h.

Member Typedef Documentation

map_value_type

using Subscriptor::map_value_type = decltype(counter_map)::value_type

privateinherited

The data type used in counter_map.

Definition at line 229 of file subscriptor.h.

map_iterator

using Subscriptor::map_iterator = decltype(counter_map)::iterator

privateinherited

The iterator type used in counter_map.

Definition at line 234 of file subscriptor.h.

Constructor & Destructor Documentation

Monomial()

template<typename number >

Polynomials::Monomial< number >::Monomial	(	const unsigned int	n,
		const double	coefficient = 1. )

Constructor, taking the degree of the monomial and an optional coefficient as arguments.

Definition at line 542 of file polynomial.cc.

Member Function Documentation

generate_complete_basis()

template<typename number >

std::vector< Polynomial< number > > Polynomials::Monomial< number >::generate_complete_basis ( const unsigned int degree )

static

Return a vector of Monomial objects of degree zero through degree, which then spans the full space of polynomials up to the given degree. This function may be used to initialize the TensorProductPolynomials and PolynomialSpace classes.

Definition at line 550 of file polynomial.cc.

make_vector()

template<typename number >

std::vector< number > Polynomials::Monomial< number >::make_vector ( unsigned int n, const double coefficient )

staticprivate

Needed by constructor.

Definition at line 532 of file polynomial.cc.

value() [1/3]

template<typename number >

number Polynomials::Polynomial< number >::value ( const number x ) const

inlineinherited

Return the value of this polynomial at the given point.

This function uses the most numerically stable evaluation algorithm for the provided form of the polynomial. If the polynomial is in the product form of roots, the evaluation is based on products of the form (x - x_i), whereas the Horner scheme is used for polynomials in the coefficient form.

Definition at line 826 of file polynomial.h.

value() [2/3]

template<typename number >

void Polynomials::Polynomial< number >::value ( const number x, std::vector< number > & values ) const

inherited

Return the values and the derivatives of the Polynomial at point x. values[i], i=0,...,values.size()-1 includes the ith derivative. The number of derivatives to be computed is thus determined by the size of the array passed.

This function uses the Horner scheme for numerical stability of the evaluation for polynomials in the coefficient form or the product of terms involving the roots if that representation is used.

Definition at line 85 of file polynomial.cc.

value() [3/3]

template<typename number >

template<typename Number2 >

void Polynomials::Polynomial< number >::value ( const Number2 x, const unsigned int n_derivatives, Number2 * values ) const

inlineinherited

Return the values and the derivatives of the Polynomial at point x. values[i], i=0,...,n_derivatives includes the ith derivative. The number of derivatives to be computed is determined by n_derivatives and values has to provide sufficient space for n_derivatives + 1 values.

This function uses the most numerically stable evaluation algorithm for the provided form of the polynomial. If the polynomial is in the product form of roots, the evaluation is based on products of the form (x - x_i), whereas the Horner scheme is used for polynomials in the coefficient form.

The template type Number2 must implement arithmetic operations such as additions or multiplication with the type number of the polynomial, and must be convertible from number by operator=.

Definition at line 856 of file polynomial.h.

values_of_array()

template<typename number >

template<std::size_t n_entries, typename Number2 >

void Polynomials::Polynomial< number >::values_of_array ( const std::array< Number2, n_entries > & points, const unsigned int n_derivatives, std::array< Number2, n_entries > * values ) const

inlineinherited

Similar to the function above, but evaluate the polynomials on several positions at once, as described by the array argument points. This function is can be faster than the other function when the same polynomial should be evaluated on several positions at once, e.g., the x,y,z coordinates of a point for tensor-product polynomials.

The template type Number2 must implement arithmetic operations such as additions or multiplication with the type number of the polynomial, and must be convertible from number by operator=.

Definition at line 874 of file polynomial.h.

degree()

template<typename number >

unsigned int Polynomials::Polynomial< number >::degree ( ) const

inlineinherited

Degree of the polynomial. This is the degree reflected by the number of coefficients provided by the constructor. Leading non-zero coefficients are not treated separately.

Definition at line 809 of file polynomial.h.

scale() [1/2]

template<typename number >

void Polynomials::Polynomial< number >::scale ( const number factor )

inherited

Scale the abscissa of the polynomial. Given the polynomial p(t) and the scaling t = ax, then the result of this operation is the polynomial q, such that q(x) = p(t).

The operation is performed in place.

Definition at line 150 of file polynomial.cc.

scale() [2/2]

template<typename number >

void Polynomials::Polynomial< number >::scale ( std::vector< number > & coefficients, const number factor )

staticprotectedinherited

This function performs the actual scaling.

Definition at line 133 of file polynomial.cc.

shift() [1/2]

template<typename number >

template<typename number2 >

void Polynomials::Polynomial< number >::shift ( const number2 offset )

inherited

Shift the abscissa oft the polynomial. Given the polynomial p(t) and the shift t = x + a, then the result of this operation is the polynomial q, such that q(x) = p(t).

The template parameter allows to compute the new coefficients with higher accuracy, since all computations are performed with type number2. This may be necessary, since this operation involves a big number of additions. On a Sun Sparc Ultra with Solaris 2.8, the difference between double and long double was not significant, though.

The operation is performed in place, i.e. the coefficients of the present object are changed.

Definition at line 424 of file polynomial.cc.

shift() [2/2]

template<typename number >

template<typename number2 >

void Polynomials::Polynomial< number >::shift ( std::vector< number > & coefficients, const number2 shift )

staticprotectedinherited

This function performs the actual shift

Definition at line 362 of file polynomial.cc.

derivative()

template<typename number >

Polynomial< number > Polynomials::Polynomial< number >::derivative ( ) const

inherited

Compute the derivative of a polynomial.

Definition at line 443 of file polynomial.cc.

primitive()

template<typename number >

Polynomial< number > Polynomials::Polynomial< number >::primitive ( ) const

inherited

Compute the primitive of a polynomial. the coefficient of the zero order term of the polynomial is zero.

Definition at line 472 of file polynomial.cc.

operator*=() [1/2]

template<typename number >

Polynomial< number > & Polynomials::Polynomial< number >::operator*= ( const double s )

inherited

Multiply with a scalar.

Definition at line 188 of file polynomial.cc.

operator*=() [2/2]

template<typename number >

Polynomial< number > & Polynomials::Polynomial< number >::operator*= ( const Polynomial< number > & p )

inherited

Multiply with another polynomial.

Definition at line 206 of file polynomial.cc.

operator+=()

template<typename number >

Polynomial< number > & Polynomials::Polynomial< number >::operator+= ( const Polynomial< number > & p )

inherited

Add a second polynomial.

Definition at line 253 of file polynomial.cc.

operator-=()

template<typename number >

Polynomial< number > & Polynomials::Polynomial< number >::operator-= ( const Polynomial< number > & p )

inherited

Subtract a second polynomial.

Definition at line 295 of file polynomial.cc.

operator==()

template<typename number >

bool Polynomials::Polynomial< number >::operator== ( const Polynomial< number > & p ) const

inherited

Test for equality of two polynomials.

Definition at line 331 of file polynomial.cc.

print()

template<typename number >

void Polynomials::Polynomial< number >::print ( std::ostream & out ) const

inherited

Print coefficients.

Definition at line 499 of file polynomial.cc.

serialize()

template<typename number >

template<class Archive >

void Polynomials::Polynomial< number >::serialize ( Archive & ar, const unsigned int version )

inlineinherited

Write or read the data of this object to or from a stream for the purpose of serialization using the BOOST serialization library.

Definition at line 1031 of file polynomial.h.

memory_consumption()

template<typename number >

std::size_t Polynomials::Polynomial< number >::memory_consumption ( ) const

virtualinherited

Return an estimate (in bytes) for the memory consumption of this object.

Definition at line 518 of file polynomial.cc.

multiply()

template<typename number >

void Polynomials::Polynomial< number >::multiply ( std::vector< number > & coefficients, const number factor )

staticprotectedinherited

Multiply polynomial by a factor.

Definition at line 175 of file polynomial.cc.

transform_into_standard_form()

template<typename number >

void Polynomials::Polynomial< number >::transform_into_standard_form ( )

protectedinherited

Transform polynomial form of product of linear factors into standard form, \(\sum_i a_i x^i\). Deletes all data structures related to the product form.

Definition at line 96 of file polynomial.cc.

subscribe()

void Subscriptor::subscribe ( std::atomic< bool > *const validity, const std::string & identifier = "" ) const

inherited

Subscribes a user of the object by storing the pointer validity. The subscriber may be identified by text supplied as identifier.

Definition at line 135 of file subscriptor.cc.

unsubscribe()

void Subscriptor::unsubscribe ( std::atomic< bool > *const validity, const std::string & identifier = "" ) const

inherited

Unsubscribes a user from the object.

Note

The identifier and the validity pointer must be the same as the one supplied to subscribe().

Definition at line 155 of file subscriptor.cc.

n_subscriptions()

unsigned int Subscriptor::n_subscriptions ( ) const

inlineinherited

Return the present number of subscriptions to this object. This allows to use this class for reference counted lifetime determination where the last one to unsubscribe also deletes the object.

Definition at line 300 of file subscriptor.h.

list_subscribers() [1/2]

template<typename StreamType >

void Subscriptor::list_subscribers ( StreamType & stream ) const

inlineinherited

List the subscribers to the input stream.

Definition at line 317 of file subscriptor.h.

list_subscribers() [2/2]

void Subscriptor::list_subscribers ( ) const

inherited

List the subscribers to deallog.

Definition at line 203 of file subscriptor.cc.

check_no_subscribers()

void Subscriptor::check_no_subscribers ( ) const

privatenoexceptinherited

Check that there are no objects subscribing to this object. If this check passes then it is safe to destroy the current object. It this check fails then this function will either abort or print an error message to deallog (by using the AssertNothrow mechanism), but will not throw an exception.

Note

Since this function is just a consistency check it does nothing in release mode.

If this function is called when there is an uncaught exception then, rather than aborting, this function prints an error message to the standard error stream and returns.

Definition at line 52 of file subscriptor.cc.

Member Data Documentation

coefficients

template<typename number >

std::vector<number> Polynomials::Polynomial< number >::coefficients

protectedinherited

Coefficients of the polynomial \(\sum_i a_i x^i\). This vector is filled by the constructor of this class and may be passed down by derived classes.

This vector cannot be constant since we want to allow copying of polynomials.

Definition at line 305 of file polynomial.h.

in_lagrange_product_form

template<typename number >

bool Polynomials::Polynomial< number >::in_lagrange_product_form

protectedinherited

Stores whether the polynomial is in Lagrange product form, i.e., constructed as a product \((x-x_0) (x-x_1) \ldots (x-x_n)/c\), or not.

Definition at line 311 of file polynomial.h.

lagrange_support_points

template<typename number >

std::vector<number> Polynomials::Polynomial< number >::lagrange_support_points

protectedinherited

If the polynomial is in Lagrange product form, i.e., constructed as a product \((x-x_0) (x-x_1) \ldots (x-x_n)/c\), store the shifts \(x_i\).

Definition at line 317 of file polynomial.h.

lagrange_weight

template<typename number >

number Polynomials::Polynomial< number >::lagrange_weight

protectedinherited

If the polynomial is in Lagrange product form, i.e., constructed as a product \((x-x_0) (x-x_1) \ldots (x-x_n)/c\), store the weight c.

Definition at line 323 of file polynomial.h.

counter

std::atomic<unsigned int> Subscriptor::counter

mutableprivateinherited

Store the number of objects which subscribed to this object. Initially, this number is zero, and upon destruction it shall be zero again (i.e. all objects which subscribed should have unsubscribed again).

The creator (and owner) of an object is counted in the map below if HE manages to supply identification.

We use the mutable keyword in order to allow subscription to constant objects also.

This counter may be read from and written to concurrently in multithreaded code: hence we use the std::atomic class template.

Definition at line 218 of file subscriptor.h.

counter_map

std::map<std::string, unsigned int> Subscriptor::counter_map

mutableprivateinherited

In this map, we count subscriptions for each different identification string supplied to subscribe().

Definition at line 224 of file subscriptor.h.

validity_pointers

std::vector<std::atomic<bool> *> Subscriptor::validity_pointers

mutableprivateinherited

In this vector, we store pointers to the validity bool in the SmartPointer objects that subscribe to this class.

Definition at line 240 of file subscriptor.h.

object_info

const std::type_info* Subscriptor::object_info

mutableprivateinherited

Pointer to the typeinfo object of this object, from which we can later deduce the class name. Since this information on the derived class is neither available in the destructor, nor in the constructor, we obtain it in between and store it here.

Definition at line 248 of file subscriptor.h.

mutex

std::mutex Subscriptor::mutex

staticprivateinherited

A mutex used to ensure data consistency when accessing the mutable members of this class. This lock is used in the subscribe() and unsubscribe() functions, as well as in list_subscribers().

Definition at line 271 of file subscriptor.h.

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

• include/deal.II/base/polynomial.h
• source/base/polynomial.cc