id {plyr}

R Documentation

Compute a unique numeric id for each unique row in a data frame.

Description

Properties:

• order(id) is equivalent to do.call(order, df)

• rows containing the same data have the same value

• if drop = FALSE then room for all possibilites

Usage

id(.variables, drop = FALSE)

Arguments

.variables	list of variables
drop	drop unusued factor levels?

Value

a numeric vector with attribute n, giving total number of possibilities

See Also

id_var

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