nlevels 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
Examples
nlevels(gl(3, 7)) # = 3
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Licensed under the GNU General Public License.