[R] number of distinct values in a dataframe

[John Fox]

Dear Rado and Doug,

At 02:13 PM 9/22/2003 -0500, Douglas Bates wrote:
>Rado Bonk <rbonk at host.sk> writes:
>
> > How can I found the number of a distinct values in a data frame
> > (occurrence of distinct values)? The dataframe consists of several
> > thousands integer numbers.
>
>It is not clear if you are asking about the number of unique values in
>a column in a data frame or the number of unique rows in a data frame.
>If there is more than one column these answers could be different.
>
>The first is question is the easier one. Just use
>
>  length(unique(mydataframe$columnOfInterest))

Since the data frame consists entirely of numeric values, finding the 
number of unique values in the data frame as a whole isn't much harder:

length(unique(as.vector(as.matrix(mydataframe))))

Regards,
  John


____________________________
John Fox
Department of Sociology
McMaster University
email: jfox at mcmaster.ca
web: http://www.socsci.mcmaster.ca/jfox