[R] access list component names with lapply
Kjetil Brinchmann Halvorsen
kjetilbrinchmannhalvorsen at gmail.com
Wed Apr 19 22:32:10 CEST 2006
Thomas Girke wrote:
> I have a question regarding accessing the names of list
> components when applying a function with lapply.
>
> Here is an example that demonstrates what I'd like to do.
>
> I have a list like this one:
>
> mylist <- list(a=letters[1:10], b=letters[10:1], c=letters[1:3])
This is how I am doing this:
mapply(functuion(x,y)myfun(x, y),x, names(x)))
Kjetil
>
> Now I would like to append the names of the list components to their
> corresponding vectors with the c() function. I thought this could
> be done like in the following command, but it doesn't:
>
> lapply(mylist, function(x) { c(names(x), x) } )
>
> I know how to do this in a for loop, but lapply runs so much faster over
> large lists.
>
> Any help on this simple problem will be highly appreciated.
>
> Thomas
>
>
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