Isis 3 Programmer Reference
Public Member Functions | Static Public Member Functions | Protected Attributes | List of all members
Isis::Photometry Class Reference

#include <Photometry.h>

Collaboration diagram for Isis::Photometry:
Collaboration graph

Public Member Functions

 Photometry (Pvl &pvl)
 Create Photometry object. More...
 
virtual ~Photometry ()
 Destroy Photometry object. More...
 
void Compute (double pha, double inc, double ema, double dn, double &albedo, double &mult, double &base)
 Calculate the surface brightness. More...
 
void Compute (double pha, double inc, double ema, double deminc, double demema, double dn, double &albedo, double &mult, double &base)
 Calculate the surface brightness using ellipsoid and dem. More...
 
virtual void SetPhotomWl (double wl)
 Set the wavelength. More...
 
PhotoModel * GetPhotoModel () const
 
AtmosModel * GetAtmosModel () const
 
NormModel * GetNormModel () const
 

Static Public Member Functions

static void minbracket (double &xa, double &xb, double &xc, double &fa, double &fb, double &fc, double Func(double par, void *params), void *params)
 Double precision version of bracketing algorithm ported from Python. Solution bracketing for 1-D minimization routine. More...
 
static int brentminimizer (double x_lower, double x_upper, gsl_function *Func, double &x_minimum, double tolerance)
 Brent's method 1-D minimization routine using GSL's r8Brent minimization Algorithm. More...
 
static int brentsolver (double x_lo, double x_hi, gsl_function *Func, double tolerance, double &root)
 GSL's the Brent-Dekker method (Brent's method) combines an interpolation strategy with the bisection algorithm to estimate the root of the quadratic function. More...
 

Protected Attributes

AtmosModel * p_phtAmodel
 
PhotoModel * p_phtPmodel
 
NormModel * p_phtNmodel
 

Detailed Description

Author
????-??-?? Unknown
History:

2007-08-02 Steven Lambright - Fixed memory leak

2008-03-07 Janet Barrett - Added SetPhotomWl method to allow the application to set the p_normWavelength variable for use by MoonAlbedo normalization.

2008-06-18 Steven Koechle - Fixed Documentation Errors

2008-07-09 Steven Lambright - Fixed unit test

2011-08-19 Sharmila Prasad - Implemented brentminimizer using GSL

2011-09-15 Sharmila Prasad - Implemented brent's root solver using GSL

Definition at line 51 of file Photometry.h.

Constructor & Destructor Documentation

◆ Photometry()

Isis::Photometry::Photometry ( Pvl &  pvl)

Create Photometry object.

Parameters
pvlA pvl object containing a valid Photometry specification
See also
photometry.doc

Definition at line 22 of file Photometry.cpp.

References _FILEINFO_, Isis::AtmosModelFactory::Create(), Isis::PhotoModelFactory::Create(), Isis::NormModelFactory::Create(), Isis::PvlObject::hasObject(), and Isis::IException::User.

◆ ~Photometry()

Isis::Photometry::~Photometry ( )
virtual

Destroy Photometry object.

Definition at line 45 of file Photometry.cpp.

Member Function Documentation

◆ brentminimizer()

int Isis::Photometry::brentminimizer ( double  x_lower,
double  x_upper,
gsl_function *  Func,
double &  x_minimum,
double  tolerance 
)
static

Brent's method 1-D minimization routine using GSL's r8Brent minimization Algorithm.

The Brent minimization algorithm combines a parabolic interpolation with the golden section algorithm.

This produces a fast algorithm which is still robust. The outline of the algorithm can be summarized as follows: on each iteration Brent's method approximates the function using an interpolating parabola through three existing points. The minimum of the parabola is taken as a guess for the minimum. If it lies within the bounds of the current interval then the interpolating point is accepted, and used to generate a smaller interval. If the interpolating point is not accepted then the algorithm falls back to an ordinary golden section step. The full details of Brent's method include some additional checks to improve convergence.

Author
Sharmila Prasad (8/15/2011)
Parameters
x_lower- x_lower interval
x_upper- x_upper interval
Func- gsl_function, high-level driver for the algorithm Continuous function of one variable for the minimizers to operate on
x_minimum- x_minimum calculated parabola min value
Returns
double - status

Definition at line 168 of file Photometry.cpp.

◆ brentsolver()

int Isis::Photometry::brentsolver ( double  x_lo,
double  x_hi,
gsl_function *  Func,
double  tolerance,
double &  root 
)
static

GSL's the Brent-Dekker method (Brent's method) combines an interpolation strategy with the bisection algorithm to estimate the root of the quadratic function.

GSL's the Brent-Dekker method (referred to here as Brent's method) combines an interpolation strategy with the bisection algorithm.

This produces a fast algorithm which is still robust.On each iteration Brent's method approximates the function using an interpolating curve. On the first iteration this is a linear interpolation of the two endpoints. For subsequent iterations the algorithm uses an inverse quadratic fit to the last three points, for higher accuracy. The intercept of the interpolating curve with the x-axis is taken as a guess for the root. If it lies within the bounds of the current interval then the interpolating point is accepted, and used to generate a smaller interval. If the interpolating point is not accepted then the algorithm falls back to an ordinary bisection step.

The best estimate of the root is taken from the most recent interpolation or bisection.

Author
Sharmila Prasad (9/15/2011)
Parameters
x_lo- Initial lower search interval
x_hi- Initial higher search interval
Func- Continuous function of one variable for the root finders to operate on
tolerance- Root Error Tolerance
root- Output calculated root
Returns
int - Algorithm status

Definition at line 125 of file Photometry.cpp.

◆ Compute() [1/2]

void Isis::Photometry::Compute ( double  pha,
double  inc,
double  ema,
double  dn,
double &  albedo,
double &  mult,
double &  base 
)

Calculate the surface brightness.

Calculate the surface brightness using only ellipsoid.

Returns
Returns the surface brightness

Definition at line 77 of file Photometry.cpp.

References Isis::NormModel::CalcNrmAlbedo().

◆ Compute() [2/2]

void Isis::Photometry::Compute ( double  pha,
double  inc,
double  ema,
double  deminc,
double  demema,
double  dn,
double &  albedo,
double &  mult,
double &  base 
)

Calculate the surface brightness using ellipsoid and dem.

Returns
Returns the surface brightness

Definition at line 92 of file Photometry.cpp.

References Isis::NormModel::CalcNrmAlbedo().

◆ minbracket()

void Isis::Photometry::minbracket ( double &  xa,
double &  xb,
double &  xc,
double &  fa,
double &  fb,
double &  fc,
double   Funcdouble par, void *params,
void *  params 
)
static

Double precision version of bracketing algorithm ported from Python. Solution bracketing for 1-D minimization routine.

This bracketing algorithm was taken from http://cxc.harvard.edu/sherpa/methods/fminpowell.py.txt and converted to C++.

Definition at line 207 of file Photometry.cpp.

References _FILEINFO_, and Isis::IException::User.

◆ SetPhotomWl()

void Isis::Photometry::SetPhotomWl ( double  wl)
virtual

Set the wavelength.

Set the wavelength parameter.

This value is obtained from the BandBin Center keyword of the image.

Definition at line 67 of file Photometry.cpp.

References Isis::NormModel::SetNormWavelength().

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