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SpheGeometry Class Referenceabstract

#include <SpheGeometry.hpp>

Inheritance diagram for SpheGeometry:
Inheritance graph
[legend]

Public Member Functions

virtual double density (double r) const =0
 
double density (Position bfr) const override
 
int dimension () const override
 
Position generatePosition () const override
 
virtual double randomRadius () const =0
 
virtual double Sigmar () const =0
 
double SigmaX () const override
 
double SigmaY () const override
 
double SigmaZ () const override
 
virtual double density (Position bfr) const =0
 
virtual int dimension () const =0
 
virtual Position generatePosition () const =0
 
virtual double SigmaX () const =0
 
virtual double SigmaY () const =0
 
virtual double SigmaZ () 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 ItemgetItemProperty (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)
 
Itemoperator= (const Item &)=delete
 
Itemparent () 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

 SpheGeometry ()
 
- Protected Member Functions inherited from Geometry
 Geometry ()
 
Randomrandom () const
 
void setupSelfBefore () override
 
- Protected Member Functions inherited from SimulationItem
 SimulationItem ()
 
virtual bool offersInterface (const std::type_info &interfaceTypeInfo) const
 
virtual void setupSelfAfter ()
 
virtual void setupSelfBefore ()
 
- Protected Member Functions inherited from Item
 Item ()
 

Private Types

using BaseType = Geometry
 
using ItemType = SpheGeometry
 

Friends

class ItemRegistry
 

Detailed Description

The SpheGeometry class is an abstract subclass of the general Geometry class, and serves as a base class for spherically symmetric geometries, i.e. geometries where the density depends only on the modulus \(r = |{\bf{r}}|\) of the position vector.

Constructor & Destructor Documentation

◆ SpheGeometry()

SpheGeometry::SpheGeometry ( )
inlineprotected

Default constructor for abstract Item subclass SpheGeometry : "a spherically symmetric geometry" .

Member Function Documentation

◆ density() [1/2]

virtual double SpheGeometry::density ( double  r) const
pure virtual

This pure virtual function returns the density \(\rho(r)\) at a radius \(r\).

Implemented in EinastoGeometry, GammaGeometry, GaussianGeometry, PlummerGeometry, PseudoSersicGeometry, SersicGeometry, and ShellGeometry.

◆ density() [2/2]

double SpheGeometry::density ( Position  bfr) const
overridevirtual

This function returns the density \(\rho({\bf{r}})\) at the position \({\bf{r}}\). For spherically symmetric geometries, the density only depends on the modulus \(r=|{\bf{r}}|\) of the position vector, such that only the member function \(\rho(r)\) needs to be defined.

Implements Geometry.

◆ dimension()

int SpheGeometry::dimension ( ) const
overridevirtual

This function returns the dimension of the geometry, which is 1 for all subclasses of this class since it is a base class for spherically symmetric geometries.

Implements Geometry.

◆ generatePosition()

Position SpheGeometry::generatePosition ( ) const
overridevirtual

This pure virtual function generates a random position from the geometry, by drawing a random point from the three-dimensional probability density \(p({\bf{r}})\, {\text{d}}{\bf{r}} = \rho({\bf{r}})\, {\text{d}}{\bf{r}}\). In spherical symmetry, this three-dimensional probability density is separable into a radial component and a direction component:

\[ p({\bf{r}})\, {\text{d}}{\bf{r}} = \left[ 4\pi\, \rho(r)\, r^2\, {\text{d}}r \right] \left[ \frac{{\text{d}}{\bf{k}}}{4\pi} \right]. \]

A random position can hence be constructed by combining a random direction on the unit sphere with a radius randomly generated from the one-dimensional probability density

\[ p(r)\,{\text{d}}r = 4\pi\, \rho(r)\, r^2\, {\text{d}}r. \]

The former is found through the general function randomDirection(), whereas the latter can be found through the member function randomradius(), which has to be provided in each class derived from the SpheGeometry class.

Implements Geometry.

◆ randomRadius()

virtual double SpheGeometry::randomRadius ( ) const
pure virtual

This pure virtual function returns a radius randomly generated from the one-dimensional probability distribution

\[ p(r)\, {\text{d}}r = 4\pi\, \rho(r)\, r^2\, {\text{d}}r. \]

Implemented in EinastoGeometry, GammaGeometry, GaussianGeometry, PlummerGeometry, PseudoSersicGeometry, SersicGeometry, and ShellGeometry.

◆ Sigmar()

virtual double SpheGeometry::Sigmar ( ) const
pure virtual

This pure virtual function returns the radial surface density, i.e. the integration of the density along a line starting at the centre of the coordinate system,

\[ \Sigma_r = \int_0^\infty \rho(r)\,{\text{d}}r. \]

Implemented in EinastoGeometry, GammaGeometry, GaussianGeometry, PlummerGeometry, PseudoSersicGeometry, SersicGeometry, and ShellGeometry.

◆ SigmaX()

double SpheGeometry::SigmaX ( ) const
overridevirtual

This function returns the X-axis surface density, i.e. the integration of the density along the entire X-axis,

\[ \Sigma_X = \int_{-\infty}^\infty \rho(x,0,0)\,{\text{d}}x. \]

For a spherical geometry, we can write \( \Sigma_X = 2\,\Sigma_r \), where \( \Sigma_r \) is the radial surface density.

Implements Geometry.

◆ SigmaY()

double SpheGeometry::SigmaY ( ) const
overridevirtual

This function returns the Y-axis surface density, i.e. the integration of the density along the entire Y-axis,

\[ \Sigma_Y = \int_{-\infty}^\infty \rho(0,y,0)\,{\text{d}}y. \]

For a spherical geometry, we can write \( \Sigma_Y = 2\,\Sigma_r \), where \( \Sigma_r \) is the radial surface density.

Implements Geometry.

◆ SigmaZ()

double SpheGeometry::SigmaZ ( ) const
overridevirtual

This function returns the Z-axis surface density, i.e. the integration of the density along the entire Z-axis,

\[ \Sigma_Z = \int_{-\infty}^\infty \rho(0,0,z)\,{\text{d}}z. \]

For a spherical geometry, we can write \( \Sigma_Z = 2\,\Sigma_r \), where \( \Sigma_r \) is the radial surface density.

Implements Geometry.


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