> On May 2, 2018, at 2:43 PM, David L Carlson <dcarl...@tamu.edu> wrote:
>
> Typo: dat[[z]] should be x[[z]]:
>
> x2 <- do.call(rbind, lapply(names(x), function(z)
> data.frame(type=z, x[[z]])))
> x2
> type x y
> 1 A 1 3
> 2 A 2 4
> 3 B 5 7
> 4 B 6 8
Sometimes one want to "bind" list that have some columns in common and others
that you want to include from one but leave as NA for the rows from the other.
The rbind.list function from package-plyr is from the pre-tidy/tibble era of
Hadley's efforts and provides that facility out of the box. It also seems to
"work" with the do.call(rbind strategy for named lists above.
x <- list(A=mtcars[c("mpg", "wt")] , B=mtcars[c("wt", "cyl")]) #mtcars
x2 <- do.call(rbind.fill, lapply(names(x), function(z)
data.frame(type=z, x[[z]])))
str(x2)
#---------
'data.frame': 64 obs. of 4 variables:
type: Factor w/ 2 levels "A","B": 1 1 1 1 1 1 1 1 1 1 ...
mpg : num 21 21 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 ...
wt : num 2.62 2.88 2.32 3.21 3.44 ...
cyl : num NA NA NA NA NA NA NA NA NA NA ...
--
David, the other.
>
> David C
>
> -----Original Message-----
> From: R-help <r-help-boun...@r-project.org> On Behalf Of David L Carlson
> Sent: Wednesday, May 2, 2018 3:51 PM
> To: William Dunlap <wdun...@tibco.com>; Kevin E. Thorpe
> <kevin.tho...@utoronto.ca>
> Cc: r-help mailing list <r-help@r-project.org>
> Subject: Re: [R] Converting a list to a data frame
>
> Or add the type column first and then rbind:
>
> x <- list(A=data.frame(x=1:2, y=3:4),B=data.frame(x=5:6,y=7:8))
> x2 <- do.call(rbind, lapply(names(x), function(z)
> data.frame(type=z, dat[[z]])))
>
> ----------------------------------------
> David L Carlson
> Department of Anthropology
> Texas A&M University
> College Station, TX 77843-4352
>
> -----Original Message-----
> From: R-help <r-help-boun...@r-project.org> On Behalf Of William Dunlap via
> R-help
> Sent: Wednesday, May 2, 2018 12:28 PM
> To: Kevin E. Thorpe <kevin.tho...@utoronto.ca>
> Cc: R Help Mailing List <r-help@r-project.org>
> Subject: Re: [R] Converting a list to a data frame
>
>> x1 <- do.call(rbind, c(x, list(make.row.names=FALSE)))
>> x2 <- cbind(type=rep(names(x), vapply(x, nrow, 0)), x1)
>> str(x2)
> 'data.frame': 4 obs. of 3 variables:
> $ type: Factor w/ 2 levels "A","B": 1 1 2 2
> $ x : int 1 2 5 6
> $ y : int 3 4 7 8
>
>
> Bill Dunlap
> TIBCO Software
> wdunlap tibco.com
>
> On Wed, May 2, 2018 at 10:11 AM, Kevin E. Thorpe <kevin.tho...@utoronto.ca>
> wrote:
>
>> I suspect this is pretty easy, but I'm having trouble figuring it out.
>> Basically, I have a list of data frames such as the following example:
>>
>> list(A=data.frame(x=1:2, y=3:4),B=data.frame(x=5:6,y=7:8))
>>
>> I would like to turn this into data frame where the list elements are
>> essentially rbind'ed together and the element name becomes a new variable.
>> For example, I would like to turn the list above into a data frame
>> that looks like this:
>>
>> data.frame(type=c("A","A","B","B"),x=c(1:2,5:6),y=c(3:4,7:8))
>>
>> Appreciate any pointers.
>>
>> Kevin
>>
>> --
>> Kevin E. Thorpe
>> Head of Biostatistics, Applied Health Research Centre (AHRC) Li Ka
>> Shing Knowledge Institute of St. Michael's Hospital Assistant
>> Professor, Dalla Lana School of Public Health University of Toronto
>> email: kevin.tho...@utoronto.ca Tel: 416.864.5776 Fax: 416.864.3016
>>
>> ______________________________________________
>> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide http://www.R-project.org/posti
>> ng-guide.html and provide commented, minimal, self-contained,
>> reproducible code.
>>
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
> ______________________________________________
> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
> ______________________________________________
> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
David Winsemius
Alameda, CA, USA
'Any technology distinguishable from magic is insufficiently advanced.'
-Gehm's Corollary to Clarke's Third Law
______________________________________________
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
