## org.biojava.bio.dist
Interface DistributionTrainer

All Known Implementing Classes:
  IgnoreCountsTrainer, SimpleDistribution.Trainer, SimpleDistributionTrainer

    public interface DistributionTrainer

An object that can be used to train a distribution up.

This lets the distribution implementation handle counts or distributions in the best way possible.

Since:
  1.0
Author:
  Matthew Pocock

Method Summary
`void` `addCount(DistributionTrainerContext dtc, AtomicSymbol sym, double times)` Registers that sym was counted in this state.
`void` `clearCounts(DistributionTrainerContext dtc)` Clears all of the counts to zero.
`double` `getCount(DistributionTrainerContext dtc, AtomicSymbol sym)` Get the current count for this state.
`void` `train(DistributionTrainerContext dtc, double weight)` Trains the Distribution, given a null model.

Method Detail

### addCount

    void addCount(DistributionTrainerContext dtc,
                  AtomicSymbol sym,
                  double times)
                  throws IllegalSymbolException

  Registers that sym was counted in this state.

  This method may be called multiple times with the same symbol. In this case, the times should be summed.

  Parameters:
    `dtc` - the DistributionTrainerContext within which the count was added
    `sym` - the Symbol seen
    `times` - the number of times to add
  Throws:
    `IllegalSymbolException` - if sym is not recognised

### getCount

    double getCount(DistributionTrainerContext dtc,
                    AtomicSymbol sym)
                    throws IllegalSymbolException

  Get the current count for this state.

  This method may be called multiple times with the same symbol. Each time it should return the agregate of the counts added with addCount since the last invocation of clearCounts.

  Parameters:
    `dtc` - the DistributionTrainerContext within which the count was added
    `sym` - the Symbol seen
  Returns:
    the agregate of the counts
  Throws:
    `IllegalSymbolException` - if sym is not recognised

### train

    void train(DistributionTrainerContext dtc,
               double weight)
               throws ChangeVetoException

  Trains the Distribution, given a null model.

  This will use the information collected with multiple addCount calls, and the null model to generate the new weights.

  This method should not modify the underlying counts.

  Parameters:
    `dtc` - the context to use
    `weight` - how many lots of the null model to add
  Throws:
    `ChangeVetoException` - if the distribution could not have its weights modified

### clearCounts

    void clearCounts(DistributionTrainerContext dtc)

  Clears all of the counts to zero.