bdm::mgamma_fix Class Reference

Gamma random walk around a fixed point. More...

#include <exp_family.h>

Public Member Functions
	mgamma_fix ()
	Constructor.
void	set_parameters (double k0, vec ref0, double l0)
	Set value of `k`.
void	condition (const vec &val)
void	set_parameters (double k, const vec &beta0)
	Set value of `k`.
void	from_setting (const Setting &set)
egamma &	e ()
	access function to iepdf
vec	samplecond (const vec &cond)
	Reimplements samplecond using `condition()`.
double	evallogcond (const vec &val, const vec &cond)
	Reimplements evallogcond using `condition()`.
virtual vec	evallogcond_m (const mat &Dt, const vec &cond)
	Efficient version of evallogcond for matrices.
virtual vec	evallogcond_m (const Array< vec > &Dt, const vec &cond)
	Efficient version of evallogcond for Array<vec>.
virtual mat	samplecond_m (const vec &cond, int N)
	Efficient version of samplecond.
virtual string	to_string ()
	This method returns a basic info about the current instance.
virtual void	to_setting (Setting &set) const
	This method save all the instance properties into the Setting structure.
virtual void	validate ()
	This method TODO.
Access to attributes

RV	_rv () const
RV	_rvc ()
int	dimension () const
int	dimensionc ()
Connection to other objects

void	set_rvc (const RV &rvc0)
void	set_rv (const RV &rv0)
bool	isnamed ()
Protected Member Functions
void	set_ep (epdf &iepdf)
	set internal pointer `ep` to point to given `iepdf`
void	set_ep (epdf *iepdfp)
	set internal pointer `ep` to point to given `iepdf`
Protected Attributes
double	l
	parameter l
vec	refl
	reference vector
double	k
	Constant .
vec &	_beta
	cache of iepdf.beta
egamma	iepdf
	Internal epdf used for sampling.
int	dimc
	dimension of the condition
RV	rvc
	random variable in condition

Detailed Description

Gamma random walk around a fixed point.

Mean value, $\mu$ , of this density is given by a geometric combination of rvc and given fixed point, $p$ . $l$ is the coefficient of the geometric combimation

$\mu = \mu_{t-1} ^{l} p^{1-l}$

Standard deviation of the random walk is proportional to one $k$ -th the mean. This is achieved by setting $\alpha=k$ and $\beta=k/\mu$ .

The standard deviation of the walk is then: $\mu/\sqrt(k)$ .

Member Function Documentation

void bdm::mgamma_fix::condition ( const vec & cond ) [inline, virtual]

Update iepdf so that it represents this mpdf conditioned on rvc = cond This function provides convenient reimplementation in offsprings

Reimplemented from bdm::mgamma.

References bdm::mgamma::_beta, bdm::mgamma::k, l, and refl.

void bdm::mgamma::from_setting ( const Setting & set ) [inline, virtual, inherited]

Load from structure with elements:

 { alpha = [...];         // vector of alpha
   k = 1.1;               // multiplicative constant k
   rv = {class="RV",...}  // description of RV
   rvc = {class="RV",...} // description of RV in condition
 }

Reimplemented from bdm::mpdf.

References bdm::UI::get(), bdm::mgamma::k, and bdm::mgamma::set_parameters().

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

exp_family.h

bdm::mgamma_fix Class Reference

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Function Documentation