[R] ddply with mean and max...

[Hadley Wickham]

> Thats the ticket!  So mean is already set up to operate on columns but max and
> min are not?  I guess its not too important now I know ... but whats going on in
> the background that makes that happen?

Basically, this:

> mean.data.frame
function (x, ...)
sapply(x, mean, ...)
<environment: namespace:base>
> min.data.frame
Error: object 'min.data.frame' not found

There was some discussion on r-devel recently about removing
mean.data.frame to be consistent with the other summary functions
(plus the way it's currently written makes it prone to problems)

Hadley

-- 
Assistant Professor / Dobelman Family Junior Chair
Department of Statistics / Rice University
http://had.co.nz/