nunique

<p>Calculate number of unique values of a variable as efficiently as possible.</p>

internal

A set of tools that solves a common set of problems: you
need to break a big problem down into manageable pieces, operate on each
piece and then put all the pieces back together.  For example, you might
want to fit a model to each spatial location or time point in your study,
summarise data by panels or collapse high-dimensional arrays to simpler
summary statistics. The development of 'plyr' has been generously supported
by 'Becton Dickinson'.

Hadley Wickham

nunique: Number of unique values.

Description

Usage

Arguments