[R] convert a list to a data frame

[Bert Gunter]

Please first search yourself before posting.

Google on "R convert list to data frame".

-- Bert

On Wed, Apr 4, 2012 at 8:11 AM, Sam Steingold <sds at gnu.org> wrote:
> I have a huge list (returned by fromJSON) with elements like this:
>
> $`zz/3260`
> $`zz/3260`$name
> [1] "myname"
>
> $`zz/3260`$status
> [1] "active"
>
> $`zz/3260`$vectors
> $`zz/3260`$vectors$`vector/241`
> $`zz/3260`$vectors$`vector/241`$channel
> [1] "channel/300"
>
> $`zz/3260`$vectors$`vector/241`$targets
> $`zz/3260`$vectors$`vector/241`$targets[[1]]
> $`zz/3260`$vectors$`vector/241`$targets[[1]]$range_start
> [1] "0"
>
> $`zz/3260`$vectors$`vector/241`$targets[[1]]$range_end
> [1] "99"
>
> I want a data frame with these column values for the above list element:
> zz=3260, name="myname", status="active", vector=241, channel=300
> range_start=0, range_end=99
>
> (and sometimes $vectors is an empty list, yuk!)
>
> my plan is to
> 1 extract a list of fields
> 2 convert it to a vector (which I know how to put into a data frame)
>
> how do I do that?
> I can get "zz/3260" with names() and split it with gsub().
> I can get "myname" with as.vector(unlist(sapply(a,"[",1))))
>
> is there a shortcut?
>
> --
> Sam Steingold (http://sds.podval.org/) on Ubuntu 11.10 (oneiric) X 11.0.11004000
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>
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-- 

Bert Gunter
Genentech Nonclinical Biostatistics

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