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SpheroidalGeometryDecorator Class Reference

#include <SpheroidalGeometryDecorator.hpp>

Inheritance diagram for SpheroidalGeometryDecorator:
Inheritance graph
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Public Member Functions

double density (double R, double z) const override
 
double flattening () const
 
Position generatePosition () const override
 
SpheGeometrygeometry () const
 
double SigmaR () const override
 
double SigmaZ () const override
 
- Public Member Functions inherited from AxGeometry
virtual double density (double R, double z) const =0
 
double density (Position bfr) const override
 
int dimension () const override
 
virtual double SigmaR () const =0
 
double SigmaX () const override
 
double SigmaY () 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

 SpheroidalGeometryDecorator ()
 
- Protected Member Functions inherited from AxGeometry
 AxGeometry ()
 
- 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 = AxGeometry
 
using ItemType = SpheroidalGeometryDecorator
 

Private Attributes

double _flattening
 
SpheGeometry_geometry
 
const double & _q
 

Friends

class ItemRegistry
 

Detailed Description

The SpheroidalGeometryDecorator class is a geometry decorator that constructs a spheroidal geometry based on a spherical geometry. The properties of a SpheroidalGeometryDecorator object are a reference to the SpheGeometry object being decorated and the flattening parameter \(q\). If the original spherical geometry is characterized by the density profile \( \rho_{\text{s}}(r) \), the new geometry has as density

\[ \rho(R,z) = \frac{1}{q}\, \rho_{\text{s}}\left(\sqrt{R^2 + \frac{z^2}{q^2}}\right). \]

This new geometry is also normalized to one.

Note that the flattening parameter can have any value \(q>0\). For \(0<q<1\), the geometry is wider than it is high. For \(q>1\), the geometry is higher than it is wide.

Constructor & Destructor Documentation

◆ SpheroidalGeometryDecorator()

SpheroidalGeometryDecorator::SpheroidalGeometryDecorator ( )
inlineprotected

Default constructor for concrete Item subclass SpheroidalGeometryDecorator : "a decorator that constructs a spheroidal variant of any spherical geometry" .

Member Function Documentation

◆ density()

double SpheroidalGeometryDecorator::density ( double  R,
double  z 
) const
overridevirtual

This function returns the density \(\rho(R,z)\) at the cylindrical radius \(R\) and the height \(z\). It just implements the analytical formula.

Implements AxGeometry.

◆ flattening()

SpheroidalGeometryDecorator::flattening ( ) const
inline

This function returns the value of the discoverable double property flattening : "the flattening parameter q" .

The minimum value for this property is "]0" .

The default value for this property is given by the conditional value expression "1" .

◆ generatePosition()

Position SpheroidalGeometryDecorator::generatePosition ( ) const
overridevirtual

This function generates a random position from the geometry, by drawing a random point from the three-dimensional probability density \(p({\bf{r}})\, {\text{d}}{\bf{r}} = \rho({\bf{r}})\, {\text{d}}{\bf{r}}\). It first generates a random position \({\bf{r}}_{\text{s}}\) by calling the generatePosition() function of the geometry being decorated and applies a simple linear transformation to the coordinates, \(x = x_{\text{s}}, y = y_{\text{s}}, z = q\,z_{\text{s}}\).

Implements Geometry.

◆ geometry()

SpheGeometry * SpheroidalGeometryDecorator::geometry ( ) const
inline

This function returns the value of the discoverable item property geometry : "the spherical geometry to be made spheroidal" .

◆ SigmaR()

double SpheroidalGeometryDecorator::SigmaR ( ) const
overridevirtual

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

\[ \Sigma_R = \int_0^\infty \rho(R,0)\,{\text{d}}R. \]

We easily obtain

\[ \Sigma_R = \frac{1}{q} \int_0^\infty \rho_{\text{orig}}(R)\,{\text{d}}R = \frac{1}{q}\,\Sigma_{r,{\text{orig}}}. \]

Implements AxGeometry.

◆ SigmaZ()

double SpheroidalGeometryDecorator::SigmaZ ( ) const
overridevirtual

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

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

We easily obtain

\[ \Sigma_Z = \frac{2}{q} \int_0^\infty \rho_{\text{orig}} \left(\frac{z}{q}\right)\,{\text{d}}z = 2 \int_0^\infty \rho_{\text{orig}}(r)\,{\text{d}}r = 2\,\Sigma_{r,{\text{orig}}}. \]

Implements Geometry.


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