calhoun.analysis.crf.solver
Class LookbackBuffer

java.lang.Object
  calhoun.analysis.crf.solver.LookbackBuffer

public final class LookbackBuffer
extends java.lang.Object

This object holds information about previous positions during the computation of betas and expectations. This allows us to quickly access data about previous positions. These objects are kept in a recycling buffer that keeps one buffer for each possible lookback.

One tricky aspect of this is that the details change slightly between the forward and backwards pass. On the forward pass, the lookback contains the information in the normal way. In the backwards pass, stable states and transitions are shifted back one base compared to the betas.

Field Summary

double[]	beta
int	betaNorm
double[]	mi
int	pos
double[]	stableState
double[]	transitionProb

Constructor Summary

LookbackBuffer(int states, int transitions)

Method Summary

void	clear() mi and stableStates are cleared as new values are entered.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

pos

public int pos

mi

public double[] mi

transitionProb

public double[] transitionProb

stableState

public double[] stableState

beta

public double[] beta

betaNorm

public int betaNorm

Constructor Detail

LookbackBuffer

public LookbackBuffer(int states,
                      int transitions)

Method Detail

clear

public void clear()

mi and stableStates are cleared as new values are entered. This fixes the others