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CylindricalVectorField Class Reference

#include <CylindricalVectorField.hpp>

Inheritance diagram for CylindricalVectorField:
Inheritance graph
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Public Member Functions

int dimension () const override
 
double exponent () const
 
double unityRadius () const
 
Vec vector (Position bfr) const override
 
virtual int dimension () const =0
 
virtual Vec vector (Position bfr) 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

 CylindricalVectorField ()
 
- Protected Member Functions inherited from VectorField
 VectorField ()
 
- 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 = VectorField
 
using ItemType = CylindricalVectorField
 

Private Attributes

double _exponent
 
double _unityRadius
 

Friends

class ItemRegistry
 

Detailed Description

CylindricalVectorField represents a vector field with vectors rotating around the z-axis in a plane parallel to the xy-plane. The orientation is clockwise when looking along with the positive z-axis, and counterclockwise when looking down from the positive z-axis towards the xy-plane.

The magnitude of the vectors varies with radial distance from the z-axis. The class has two configuration properties: the distance at which the vector magnitude becomes unity and a power law exponent. If the exponent is positive, the magnitude ramps up from zero at the z-axis to unity at the specified distance, and remains unity from there on. If the power law index is negative, the magnitude is unity from the z-axis to the specified distance, and then ramps down from there to zero at infinity.

Given the user-configurable unity radius \(R_1\ge 0\) and power-law exponent \(\alpha\), the magnitude \(v(R)\) of the vectors as a function of radial distance \(R=\sqrt{x^2+y^2}\) is given by

\[ R_1=0 \lor \alpha=0 \qquad v(R) = \begin{cases} 0 & \mathrm{for}\;R=0 \\ 1 & \mathrm{for}\;R>0 \end{cases} \]

\[ R_1>0 \land \alpha>0 \qquad v(R) = \begin{cases} 0 & \mathrm{for}\;R=0 \\ (R/R_1)^\alpha & \mathrm{for}\;0<R<R_1 \\ 1 & \mathrm{for}\;R\ge R_1 \end{cases} \]

\[ R_1>0 \land \alpha<0 \qquad v(R) = \begin{cases} 0 & \mathrm{for}\;R=0 \\ 1 & \mathrm{for}\;0<R<R_1 \\ (R/R_1)^\alpha & \mathrm{for}\;R \ge R_1 \end{cases} \]

The first equation defines the vector field for the special values \(R_1=0\) and/or \(\alpha=0\) to consist solely of unit vectors except at the z-axis, where the direction of the vector is undefined. The default value of \(R_1=0\) causes this behavior. If the unity radius is set to a value \(R_1>0\), the default value of \(\alpha=1\) specifies linear behavior: the vector magnitude scales linearly from zero at the z-axis to unity at \(R=R_1\), and stays at unity for larger radii.

When an item of this type is used, the names provided by the conditional value expression "Dimension3" are inserted into the name sets used for evaluating Boolean expressions.

Constructor & Destructor Documentation

◆ CylindricalVectorField()

CylindricalVectorField::CylindricalVectorField ( )
inlineprotected

Default constructor for concrete Item subclass CylindricalVectorField : "a vector field rotating clockwise around the z-axis" .

Member Function Documentation

◆ dimension()

int CylindricalVectorField::dimension ( ) const
overridevirtual

This function returns the dimension of the vector field, which is 3 for this class, indicating no symmetries (the vectors point in a different direction at each position).

Implements VectorField.

◆ exponent()

CylindricalVectorField::exponent ( ) const
inline

This function returns the value of the discoverable double property exponent : "the power-law exponent governing the radial dependence of the magnitude" .

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

◆ unityRadius()

CylindricalVectorField::unityRadius ( ) const
inline

This function returns the value of the discoverable double property unityRadius : "the radius where the magnitude of the vectors is unity" .

This property represents a physical quantity of type "length" .

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

The default value for this property is given by the conditional value expression "0" .

◆ vector()

Vec CylindricalVectorField::vector ( Position  bfr) const
overridevirtual

This function returns a vector that is parallel with the xy-plane and orthogonal to the cylindrical radius component of the given position \(\bf{r}\) according to the definitions given in the class header.

Implements VectorField.


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