If you look up the help page, one of the arguments to lapply
is the mysterious ...
. When we look at the Arguments section of the help page, we find the following line:
...: optional arguments to ‘FUN’.
So all you have to do is include your other argument in the lapply
call as an argument, like so:
lapply(input, myfun, arg1=6)
and lapply
, recognizing that arg1
is not an argument it knows what to do with, will automatically pass it on to myfun
. All the other apply
functions can do the same thing.
An addendum: You can use ...
when you're writing your own functions, too. For example, say you write a function that calls plot
at some point, and you want to be able to change the plot parameters from your function call. You could include each parameter as an argument in your function, but that's annoying. Instead you can use ...
(as an argument to both your function and the call to plot within it), and have any argument that your function doesn't recognize be automatically passed on to plot
.