[R] Row-wisely converting a data frame into a list

[Nutter, Benjamin]

> as.data.frame(t(df)) 

For example

> x <- as.data.frame(t(mtcars))
> typeof(x)
[1] "list"

-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]
On Behalf Of Sebastian Bauer
Sent: Tuesday, March 02, 2010 8:12 AM
To: r-help at r-project.org
Subject: [R] Row-wisely converting a data frame into a list

Hello,

is there an elegant way, how I can convert each row of a data frame into
distinct elements of a list?

In essence, what I'm looking for is something like

rows.to.lists <- function( df ) {
	ll <- NULL
	for( i in 1:nrow(df) )
		ll <- append( ll, list(df[i,]) )
	return (ll)
}

but more done more efficiently (the data frame may contain ten-thousands
of rows). I thought about using apply() but this function always returns
a matrix.

Thanks in advance!

Bye,
Sebastian

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