[R] lapply without return values?

Berwin A Turlach berwin at maths.uwa.edu.au
Fri Jan 25 10:05:11 CET 2008


G'day Rainer,

On Fri, 25 Jan 2008 10:34:32 +0200
Rainer M Krug <r.m.krug at gmail.com> wrote:

[...] 

>  > p <- data.frame(runif(10), runif(10), runif(10))
>  > lapply( p, function(ps) {x11(); plot(ps)} )
> 
> which results in three graphs and a printout:
[...]
> How can I avoid this printout without using
> 
> tmp <- lapply( p, function(ps) {x11(); plot(ps)} )?

?invisible

like in invisible(lapply( p, function(ps) {x11(); plot(ps)} ))

Note, your solution seems to involve less keystroke but has the
disadvantage of creating an object in your workspace.  

Of course, you could always do something like:

> ilapply <- function(...) invisible(lapply(...))

## perhaps better:
## ilapply <- function(X, FUN, ...) invisible(lapply(X, FUN, ...))

> ilapply(p, function(ps) {x11(); plot(ps)})

To save keystrokes in the long run. :)

HTH.

Cheers,

	Berwin

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