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

[Chuck Cleland]

newdata <- subset(mydata, mydata$myfact == 
names(which.max(table(mydata$myfact))))

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.  
> 
> I can get a list by doing:
> 
> by(data,data$pattern,subset)
> 
> And go through each element of the list counting the rows, to find the
> maximum....
> 
> BUT I can't help thinking there's a more elegant way of doing this....
> 
> The second part is figuring out the rows which have the maximum number
> of consecutive patterns which are the same... Now that I would love some
> help with... :-)
> 
> Thanks
> Mick
> 
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Chuck Cleland, Ph.D.
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