DocCollection is a virtual class for all representations of
document collections. It is made concrete by
'>DocList and
'>DocDataFrame. This is mostly to achieve an
abstraction around tabular and list representations of documents.
These are the accessors that should apply equivalently to any
derivative of DocCollection, which provides reasonable default
implementations for most of them.
ndoc(x): Gets the number of documents
nfield(x): Gets the number of fields
ids(x), ids(x) <- value: Gets or sets the document unique
identifiers (may be NULL)
fieldNames(x, includeStatic=TRUE, ...): Gets the field names
docs(x): Just returns x, as x already
represents a set of documents
meta(x): Gets an auxillary collection of “meta”
fields that hold fields that describe, rather than compose, the
documents. This feature should be considered unstable. Stay away
for now.
unmeta(x): Clears the metadata.