Find the Unique Rows in a Dataset.

DESCRIPTION:

Remove all duplicated rows from the dataset so that each row is guaranteed to be unique..

This function requires the bigdata library section to be loaded.

USAGE:

bd.unique(data, columns=NULL)

REQUIRED ARGUMENTS:

data
input data set, a bdFrame or data.frame.

OPTIONAL ARGUMENTS:

columns
names or numbers of columns which columns determine uniqueness.

VALUE:

a bdFrame or data.frame, of the same type as data. This contains only unique rows.

EXAMPLES:

## Remove all duplicate rows
bd.unique(bd.append(list(fuel.frame, fuel.frame)))
# Remove all rows with the duplicated first and second columns.
bd.unique(fuel.frame, 1:2)