madness::KernelRange Class Reference

#include <kernelrange.h>

Classes
struct	Data
struct	Restrictor
	restrictor function More...

Public Types
enum	Type { Hard , SoftErf }
	types of range restrictor functions More...

Public Member Functions
	KernelRange ()=default
	KernelRange (unsigned int N)
	KernelRange (unsigned int N, double sigma)
bool	finite () const
bool	finite_hard () const
bool	finite_soft () const
hashT	hash () const
int	iextent_x2 (double epsilon=extent_default_epsilon) const
bool	infinite () const
unsigned int	N () const
	operator bool () const
double	sigma () const
Type	type () const
double	value (double r) const

Static Public Attributes
static constexpr double	extent_default_epsilon = std::numeric_limits<double>::epsilon()

Private Member Functions
const Restrictor &	restrictor () const

Private Attributes
std::optional< Data >	data

Friends
bool	operator== (const KernelRange &r1, const KernelRange &r2)

Detailed Description

To limit the range of kernel K(x-y) it is multiplied (in user coordinates) by a restrictor function , where is identity for unrestricted kernel or one of the choices encoded by KernelRange::Type

Member Enumeration Documentation

Type

enum madness::KernelRange::Type

types of range restrictor functions

Enumerator
Hard	Heavyside (step) function: .
SoftErf	erf approximation to Heavyside function: ; in the limit $\sigma\to 0$ this becomes the Heaviside function.

Constructor & Destructor Documentation

KernelRange() [1/3]

madness::KernelRange::KernelRange ( )

default

constructs a null (i.e., infinite) kernel range

Postcondition

this->infinite()==true

Referenced by operator==.

KernelRange() [2/3]

madness::KernelRange::KernelRange ( unsigned int N, double sigma )

inline

constructs a finite soft (sigma > 0) or hard (sigma==0) kernel range

Parameters

sigma

regularization parameter (lengthscale in simulation [0,1] coordinate units) controls the softness of the range restrictor

Precondition

sigma>=0

Postcondition

this->soft()==true

References data, Hard, MADNESS_ASSERT, N(), sigma(), and SoftErf.

KernelRange() [3/3]

madness::KernelRange::KernelRange ( unsigned int N )

inline

constructs a finite (hard) kernel range

Postcondition

this->hard()==true

References data, and N().

Member Function Documentation

finite()

bool madness::KernelRange::finite ( ) const

inline

Returns

true if range is limited

References data.

Referenced by finite_hard(), finite_soft(), infinite(), operator bool(), and operator==.

finite_hard()

bool madness::KernelRange::finite_hard ( ) const

inline

Returns

true if range is limited using a hard window function (Heaviside)

References finite(), Hard, and type().

finite_soft()

bool madness::KernelRange::finite_soft ( ) const

inline

Returns

true if range is limited using a soft window function (sigmoid)

References finite(), Hard, and type().

hash()

hashT madness::KernelRange::hash ( ) const

inline

References madness::hash_combine(), madness::hash_value(), infinite(), N(), and restrictor().

iextent_x2()

int madness::KernelRange::iextent_x2 ( double epsilon = extent_default_epsilon ) const

inline

Returns

max value of |x-y| (rounded up, in units of 1/2) for which r(N/2 - |x-y|) is greater than epsilon

References data, epsilon, extent_default_epsilon, infinite(), and MADNESS_ASSERT.

infinite()

bool madness::KernelRange::infinite ( ) const

inline

Returns

true if range is unlimited

References finite().

Referenced by hash(), iextent_x2(), and value().

N()

unsigned int madness::KernelRange::N ( ) const

inline

References data.

Referenced by KernelRange(), KernelRange(), hash(), operator==, and value().

operator bool()

madness::KernelRange::operator bool ( ) const

inlineexplicit

Returns

true if range is limited

References finite().

restrictor()

const Restrictor & madness::KernelRange::restrictor ( ) const

inlineprivate

References data.

Referenced by hash(), operator==, sigma(), type(), and value().

sigma()

double madness::KernelRange::sigma ( ) const

inline

References restrictor(), and madness::KernelRange::Restrictor::sigma().

Referenced by KernelRange().

type()

Type madness::KernelRange::type ( ) const

inline

References restrictor(), and madness::KernelRange::Restrictor::type().

Referenced by finite_hard(), and finite_soft().

value()

double madness::KernelRange::value ( double r ) const

inline

Returns

value of restrictor function at N/2 - abs(r)

References std::abs(), infinite(), N(), restrictor(), and madness::KernelRange::Restrictor::value().

Referenced by madness::KernelRange::Data::compute_iextent_x2().

Friends And Related Symbol Documentation

operator==

bool operator== ( const KernelRange & r1, const KernelRange & r2 )

friend

Returns

true if r1 and r2 are equal

References KernelRange(), finite(), N(), madness::r2(), and restrictor().

Member Data Documentation

data

std::optional<Data> madness::KernelRange::data

private

Referenced by KernelRange(), KernelRange(), finite(), iextent_x2(), N(), and restrictor().

extent_default_epsilon

double madness::KernelRange::extent_default_epsilon = std::numeric_limits<double>::epsilon()

staticconstexpr

Referenced by madness::KernelRange::Data::Data(), madness::KernelRange::Data::iextent_x2(), and iextent_x2().

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

• kernelrange.h