nlevels                 package:base                 R Documentation

The Number of Levels of a Factor

Description:

     Return the number of levels which its argument has.

Usage:

     nlevels(x)

Arguments:

       x: an object, usually a factor.

Details:

     This is usually applied to a factor, but other objects can have
     levels.

     The actual factor levels (if they exist) can be obtained with the
     'levels' function.

Value:

     The length of 'levels(x)', which is zero if 'x' has no levels.

See Also:

     'levels', 'factor'.

Examples:

     nlevels(gl(3,7)) # = 3

