[R] Is there an variant of apply() that does not return anything?

[Charlie Sharpsteen]

On Thu, Nov 19, 2009 at 2:21 PM, Peng Yu <pengyu.ut at gmail.com> wrote:
> There are a few version of apply() (e.g., lapply(), sapply()). I'm
> wondering if there is one that does not return anything but just
> silently apply a function to the list argument.
>
> For example, the plot function is applied to each element in 'alist'.
> It is redundant to return anything from apply.
>
> apply(alist,function(x){ plot each element of alist})

Take a look at the l_ply(), a_ply() and d_ply() functions from
Hadley's "plyr" package.  They are a refinement and extension to the
apply family of functions and the underscore, "_", in the function
names indicates that they have no return value.


-Charlie