featureData(object)
featureData(object) <- value
fData(object)
fData(object) <- value
fvarLabels(object)
fvarLabels(object) <- value
fvarMetadata(object)
fvarMetadata(object) <- valueeSet-class
    or AnnotatedDataFrame-class.featureData returns an object containing information on both
  variable values and variable meta-data.  fvarLabels returns a
  character vector of measured variable names. fData returns a data
  frame with features as rows, variables as columns. fvarMetadata
  returns a data frame with variable names as rows, description tags
  (e.g., unit of measurement) as columns.
eSet,
  ExpressionSet