bdm::mratio Class Reference

#include <emix.h>

Inheritance diagram for bdm::mratio:

bdm::mpdf bdm::bdmroot

List of all members.


Detailed Description

Class representing ratio of two densities which arise e.g. by applying the Bayes rule. It represents density in the form:

\[ f(rv|rvc) = \frac{f(rv,rvc)}{f(rvc)} \]

where $ f(rvc) = \int f(rv,rvc) d\ rv $.

In particular this type of arise by conditioning of a mixture model.

At present the only supported operation is evallogcond().

Public Member Functions

 mratio (const epdf *nom0, const RV &rv, bool copy=false)
double evallogcond (const vec &val, const vec &cond)
 Shortcut for conditioning and evaluation of the internal epdf. In some cases, this operation can be implemented efficiently.
void ownnom ()
 Object takes ownership of nom and will destroy it.
 ~mratio ()
 Default destructor.
Matematical operations
virtual vec samplecond (const vec &cond)
 Returns a sample from the density conditioned on cond, $x \sim epdf(rv|cond)$.
virtual mat samplecond_m (const vec &cond, int N)
 Returns.
virtual void condition (const vec &cond)
 Update ep so that it represents this mpdf conditioned on rvc = cond.
virtual vec evallogcond_m (const mat &Dt, const vec &cond)
 Matrix version of evallogcond.
Access to attributes
RV _rv ()
RV _rvc ()
int dimension ()
int dimensionc ()
epdf_epdf ()
epdf_e ()
Connection to other objects
void set_rvc (const RV &rvc0)
void set_rv (const RV &rv0)
bool isnamed ()

Protected Attributes

const epdfnom
 Nominator in the form of mpdf.
epdfden
 Denominator in the form of epdf.
bool destroynom
 flag for destructor
datalink_m2e dl
 datalink between conditional and nom
int dimc
 dimension of the condition
RV rvc
 random variable in condition
epdfep
 pointer to internal epdf


Constructor & Destructor Documentation

bdm::mratio::mratio ( const epdf nom0,
const RV rv,
bool  copy = false 
) [inline]

Default constructor. By default, the given epdf is not copied! It is assumed that this function will be used only temporarily.

References bdm::epdf::_rv(), den, destroynom, bdm::mpdf::ep, bdm::RV::length(), bdm::epdf::marginal(), nom, bdm::mpdf::rvc, bdm::epdf::set_rv(), and bdm::RV::subt().


Member Function Documentation

virtual vec bdm::mpdf::samplecond ( const vec &  cond  )  [inline, virtual, inherited]

Returns a sample from the density conditioned on cond, $x \sim epdf(rv|cond)$.

Parameters:
cond is numeric value of rv

Reimplemented in bdm::mprod.

References bdm::mpdf::condition(), bdm::mpdf::ep, and bdm::epdf::sample().

Referenced by bdm::MPF< BM_T >::bayes(), bdm::PF::bayes(), and bdm::ArxDS::step().

virtual mat bdm::mpdf::samplecond_m ( const vec &  cond,
int  N 
) [inline, virtual, inherited]

Returns.

Parameters:
N samples from the density conditioned on cond, $x \sim epdf(rv|cond)$.
cond is numeric value of rv
ll is a return value of log-likelihood of the sample.

References bdm::mpdf::condition(), bdm::epdf::dimension(), bdm::mpdf::ep, and bdm::epdf::sample().


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

Generated on Wed Mar 4 18:50:20 2009 for mixpp by  doxygen 1.5.6