angular expansion of potential in azimuthal angle with coefficients being 2d spline functions of R,z More...

#include <potential.h>

Inheritance diagram for smile::CPotentialCylSpline:

Collaboration diagram for smile::CPotentialCylSpline:

Public Member Functions
	CPotentialCylSpline (size_t _Ncoefs_R, size_t _Ncoefs_z, size_t _Ncoefs_phi, const CDensity *density, double radius_min=0, double radius_max=0, double z_min=0, double z_max=0)
	init potential from analytic mass model specified by its density profile (using CPotentialDirect for intermediate potential computation)

	CPotentialCylSpline (size_t _Ncoefs_R, size_t _Ncoefs_z, size_t _Ncoefs_phi, const CPotential *potential, double radius_min=0, double radius_max=0, double z_min=0, double z_max=0)
	init potential from analytic mass model specified by a potential-density pair

	CPotentialCylSpline (const vectord &gridR, const vectord &gridz, const std::vector< vectord > &coefs)
	init potential from stored coefficients

	CPotentialCylSpline (size_t _Ncoefs_R, size_t _Ncoefs_z, size_t _Ncoefs_phi, const CPointMassSet< double > &points, SYMMETRYTYPE _sym=ST_TRIAXIAL, double radius_min=0, double radius_max=0, double z_min=0, double z_max=0)
	init potential from N-body snapshot

virtual CPotential *	clone () const
	Return a pointer to a copy of this instance of potential. More...

virtual double	Mass (const double r) const
	a modified mass estimator that only integrates withing the grid definition radius

virtual POTENTIALTYPE	PotentialType () const
	enumerable potential type

virtual const char *	PotentialName () const
	string representation of potential type

virtual SYMMETRYTYPE	symmetry () const
	returns symmetry type of this potential

virtual double	Rho (double X, double Y, double Z, double t=0) const
	returns density at given coordinates, this should obviously be overriden in derivative classes

virtual double	Phi (double X, double Y, double Z, double t=0) const
	Return potential at a given spatial point (possibly a time-varying one). More...

virtual void	Force (const double xyz[N_DIM], const double t, double force, double forceDeriv=NULL) const
	Compute forces and, optionally, force derivatives at a given point. More...

void	getCoefs (vectord gridR, vectord gridz, std::vector< vectord > *coefs) const
	retrieve coefficients of potential approximation. More...

Public Member Functions inherited from smile::CDensity
virtual double	totalMass () const
	returns estimated M(r=infinity) or -1 if mass is infinite

double	getRadiusByMass (const double m) const
	solves for Mass(r)=m

void	getRadiiByMass (const vectord &masses, vectord *radii) const
	solves for Mass(r)=m for an array of sorted values of m (more efficient than doing it one-by-one)

bool	checkMassMonotonic () const
	safety measure: check (roughly) that mass is increasing with radius

bool	checkDensityNonzero () const
	another safety measure: check that density doesn't drop to zero along any of three axes (important to assess spherical-harmonic approximation quality)

virtual double	getGamma () const
	returns inner density slope estimate (only used in BSE potential expansion for the automatic selection of shape parameter Alpha)

Static Public Member Functions
static const char *	myName ()

Private Member Functions
void	initPot (size_t _Ncoefs_R, size_t _Ncoefs_z, size_t _Ncoefs_phi, const CPotential *potential, double radius_min, double radius_max, double z_min, double z_max)
	create interpolation grid and compute potential at grid nodes

void	initSplines (const std::vector< vectord > &coefs)
	create 2d interpolation splines in scaled R,z grid

void	initDefault ()
	called as a default initialization when everything else fails

double	computePhi_m (double R, double z, int m, const CPotential *potential) const
	compute m-th azimuthal harmonic of potential (either by Fourier transform or calling the corresponding method of CPotentialDirect)

Private Attributes
SYMMETRYTYPE	mysymmetry
	may have different type of symmetry

vectord	grid_R

vectord	grid_z
	nodes of the grid in cylindrical radius and vertical direction

double	Rscale
	scaling coefficient for transforming the interpolated potential; computed as -Phi(0)/Mtotal.

std::vector< interp2d_spline * >	splines
	array of 2d splines (for each m-component in the expansion in azimuthal angle)

double	C00

double	C20

double	C40

double	C22
	multipole coefficients for extrapolation beyond the grid

Additional Inherited Members
Public Types inherited from smile::CDensity
enum	POTENTIALTYPE { PT_UNKNOWN, PT_DIRECT, PT_COMPOSITE, PT_COEFS, PT_NB, PT_BSE, PT_BSECOMPACT, PT_SPLINE, PT_CYLSPLINE, PT_LOG, PT_HARMONIC, PT_SCALEFREE, PT_SCALEFREESH, PT_SPHERICAL, PT_DEHNEN, PT_MIYAMOTONAGAI, PT_FERRERS, PT_PLUMMER, PT_ISOCHRONE, PT_PERFECTELLIPSOID, PT_NFW, PT_SERSIC, PT_EXPDISK, PT_ELLIPSOIDAL, PT_MGE }
	list of all existing types of density or density/potential models, each of them implemented in its own class More...

enum	SYMMETRYTYPE { ST_NONE = 0, ST_REFLECTION = 1, ST_PLANESYM = 2, ST_ZROTSYM = 4, ST_SPHSYM = 8, ST_TRIAXIAL = ST_REFLECTION \| ST_PLANESYM, ST_AXISYMMETRIC = ST_TRIAXIAL \| ST_ZROTSYM, ST_SPHERICAL = ST_AXISYMMETRIC \| ST_SPHSYM, ST_DEFAULT = ST_TRIAXIAL }
	Type of symmetry. More...

Detailed Description

angular expansion of potential in azimuthal angle with coefficients being 2d spline functions of R,z

Member Function Documentation

CPotential * smile::CPotentialCylSpline::clone ( ) const

virtual

Return a pointer to a copy of this instance of potential.

A standard copy constructor or assignment is disabled because of different amount of data needed to be copied in different derived classes).

Implements smile::CPotential.

void smile::CPotentialCylSpline::Force	(	const double	xyz[N_DIM],
		const double	t,
		double *	force,
		double *	forceDeriv = `NULL`
	)		const

virtual

Compute forces and, optionally, force derivatives at a given point.

Parameters

[in]	xyz	- coordinates of the point to compute forces (array of 3 numbers)
[in]	t	- time to compute forces (matters only if potential is time-dependent)
[out]	force	- computed values of -d Phi/d x_i; output array must exist and contain N_DIM values.
[out]	forceDeriv	- if not NULL, then also compute the second derivatives of potential (which is a symmetric matrix of size N_DIM^2, thus the array must be of size N_DIM*(N_DIM+1)/2 ): first 3 values contain $-d^2 \Phi/d x_i^2$ , second three contain mixed derivatives $-d^2 \Phi/d x_1 d x_2, -d^2 \Phi/d x_2 d x_3, -d^2 \Phi/d x_3 d x_1$ .

Implements smile::CPotential.

void smile::CPotentialCylSpline::getCoefs	(	vectord *	gridR,
		vectord *	gridz,
		std::vector< vectord > *	coefs
	)		const

retrieve coefficients of potential approximation.

Parameters

[out]	gridR	will be filled with the array of R-values of grid nodes
[out]	gridz	will be filled with the array of z-values of grid nodes
[out]	coefs	will contain array of sequentially stored 2d arrays (the size of the outer array equals the number of terms in azimuthal expansion, inner arrays contain gridR.size()*gridz.size() values). All output array parameters must point to existing arrays.

double smile::CPotentialCylSpline::Phi	(	double	X,
		double	Y,
		double	Z,
		double	t = `0`
	)		const

virtual

Return potential at a given spatial point (possibly a time-varying one).

Implements smile::CPotential.

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

potential.h
potential.cpp

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Member Function Documentation