# Package weka.filters.unsupervised.instance

- Class Summary
  Class | Description
  --- | ---
  NonSparseToSparse | An instance filter that converts all incoming instances into sparse format.
  Randomize | Randomly shuffles the order of instances passed through it.
  RemoveDuplicates | Removes all duplicate instances from the first batch of data it receives.
  RemoveFolds | This filter takes a dataset and outputs a specified fold for cross validation.
  RemoveFrequentValues | Determines which values (frequent or infrequent ones) of an (nominal) attribute are retained and filters the instances accordingly.
  RemoveMisclassified | A filter that removes instances which are incorrectly classified.
  RemovePercentage | A filter that removes a given percentage of a dataset.
  RemoveRange | A filter that removes a given range of instances of a dataset.
  RemoveWithValues | Filters instances according to the value of an attribute.
  Resample | Produces a random subsample of a dataset using either sampling with replacement or without replacement.
  ReservoirSample | Produces a random subsample of a dataset using the reservoir sampling Algorithm "R" by Vitter.
  SparseToNonSparse | An instance filter that converts all incoming sparse instances into non-sparse format.
  SubsetByExpression | Filters instances according to a user-specified expression. Examples: - extracting only mammals and birds from the 'zoo' UCI dataset: (CLASS is 'mammal') or (CLASS is 'bird') - extracting only animals with at least 2 legs from the 'zoo' UCI dataset: (ATT14 >= 2) - extracting only instances with non-missing 'wage-increase-second-year' from the 'labor' UCI dataset: not ismissing(ATT3) Valid options are: