[R] Subsetting a data frame by a factor, using the level that occurs the most times

[Douglas Bates]

michael watson (IAH-C) wrote:
> I think that title makes sense... I hope it does...
> 
> I have a data frame, one of the columns of which is a factor.  I want
> the rows of data that correspond to the level in that factor which
> occurs the most times.  

So first you want to determine the mode (in the sense of the most 
frequently occuring value) of the factor.   One way to do this is

names(which.max(table(fac)))

Use this comparison for the subset as

subset(data, pattern == names(which.max(table(pattern))))