SmoothingKernel Class Reference

#include <SmoothingKernel.hpp>

Inheritance diagram for SmoothingKernel:

Public Member Functions
virtual double	columnDensity (double q) const =0
virtual double	density (double u) const =0
virtual double	generateRadius () const =0
Public Member Functions inherited from SimulationItem
template<class T>
T *	find (bool setup=true) const
template<class T>
T *	interface (int levels=-999999, bool setup=true) const
virtual string	itemName () const
void	setup ()
string	typeAndName () const
Public Member Functions inherited from Item
	Item (const Item &)=delete
virtual	~Item ()
void	addChild (Item *child)
const vector< Item * > &	children () const
virtual void	clearItemListProperty (const PropertyDef *property)
void	destroyChild (Item *child)
virtual bool	getBoolProperty (const PropertyDef *property) const
virtual vector< double >	getDoubleListProperty (const PropertyDef *property) const
virtual double	getDoubleProperty (const PropertyDef *property) const
virtual string	getEnumProperty (const PropertyDef *property) const
virtual int	getIntProperty (const PropertyDef *property) const
virtual vector< Item * >	getItemListProperty (const PropertyDef *property) const
virtual Item *	getItemProperty (const PropertyDef *property) const
virtual string	getStringProperty (const PropertyDef *property) const
int	getUtilityProperty (string name) const
virtual void	insertIntoItemListProperty (const PropertyDef *property, int index, Item *item)
Item &	operator= (const Item &)=delete
Item *	parent () const
virtual void	removeFromItemListProperty (const PropertyDef *property, int index)
virtual void	setBoolProperty (const PropertyDef *property, bool value)
virtual void	setDoubleListProperty (const PropertyDef *property, vector< double > value)
virtual void	setDoubleProperty (const PropertyDef *property, double value)
virtual void	setEnumProperty (const PropertyDef *property, string value)
virtual void	setIntProperty (const PropertyDef *property, int value)
virtual void	setItemProperty (const PropertyDef *property, Item *item)
virtual void	setStringProperty (const PropertyDef *property, string value)
void	setUtilityProperty (string name, int value)
virtual string	type () const

Protected Member Functions
	SmoothingKernel ()
Random *	random () const
void	setupSelfBefore () override
Protected Member Functions inherited from SimulationItem
	SimulationItem ()
virtual bool	offersInterface (const std::type_info &interfaceTypeInfo) const
virtual void	setupSelfAfter ()
Protected Member Functions inherited from Item
	Item ()

Private Types
using	BaseType
using	ItemType

Private Attributes
Random *	_random

Friends
class	ItemRegistry

Detailed Description

SmoothingKernel is an abstract class that represents smoothing kernels that can be used to smear out points to smoothed particles. Each smoothing kernel is completely defined by the kernel density \(W(u)\) which is just a function of the normalized radius \(u=r/h\) with \(h\) the smoothing length. All smoothing kernels are spherically symmetric, have finite support, and are normalized to one, i.e.

\[ W(u)=0 \quad \text{for}\; u>1 \qquad \text{and} \qquad 4\pi \int_0^1 W(u)\, u^2\, {\text{d}}u = 1. \]

Constructor & Destructor Documentation

SmoothingKernel()

SmoothingKernel::SmoothingKernel ( )

inlineprotected

Default constructor for abstract Item subclass SmoothingKernel: "a smoothing kernel".

Member Function Documentation

columnDensity()

virtual double SmoothingKernel::columnDensity ( double q ) const

pure virtual

This function returns the projection of the smoothing kernel along a line with given impact radius (smallest distance) to the kernel's center. In formula form, this is the column density \(\Sigma(q) = 2 \int_{q}^1 \frac{W(u)\,u \,{\text{d}}u} {\sqrt{u^2-q^2}}\) of the smoothing kernel as a function of the normalized impact radius \(q=r_\text{i}/h\), or zero for \(q\ge 1\). Subclasses must implement this function appropriately.

Implemented in CubicSplineSmoothingKernel, QuarticSplineSmoothingKernel, ScaledGaussianSmoothingKernel, and UniformSmoothingKernel.

density()

virtual double SmoothingKernel::density ( double u ) const

pure virtual

This function returns the density \(W(u)\) of the smoothing kernel as a function of the normalized radius \(u\). Subclasses must implement this function appropriately.

Implemented in CubicSplineSmoothingKernel, QuarticSplineSmoothingKernel, ScaledGaussianSmoothingKernel, and UniformSmoothingKernel.

generateRadius()

virtual double SmoothingKernel::generateRadius ( ) const

pure virtual

This pure virtual function generates a random normalized radius \(u\) from the smoothing kernel, by drawing a number from the one-dimensional probability density \(p(u)\,{\text{d}}u = 4\pi\,W(u)\,u^2\, {\text{d}}u \). Subclasses must implement this function appropriately.

Implemented in CubicSplineSmoothingKernel, QuarticSplineSmoothingKernel, ScaledGaussianSmoothingKernel, and UniformSmoothingKernel.

random()

Random * SmoothingKernel::random ( ) const

inlineprotected

This function returns the simulation's random generator as a service to subclasses.

setupSelfBefore()

void SmoothingKernel::setupSelfBefore ( )

overrideprotectedvirtual

This function caches the simulation's random generator for use by subclasses.

Reimplemented from SimulationItem.

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

• SmoothingKernel.hpp