R help - Nov 2007 - Constructin a call of function including permutation of column names - how to escape parentheses?

Dear R-users,
I would like to construct a list of arguments for a function in a format
function (list(item1=c("A","B"),
item2=c("B","C")), item3=...):
The individual vectors in the list are permutations of colnames of a
dataframe.
The trouble is that I am not able to handle escaping of parentheses
correctly.

I was trying the following:
library(gregmisc)
combinations.2<-combinations(12,2,mycolnames)
combinations.2.call<-apply(combinations.2,1,function(x){do.call(paste,c(
as.list(x),sep="\",\""))})
combinations.2.call<-paste("c(\"",combinations.2.call,"\")",sep="")

but now calling call("list",combinations.2.list) doesnt work.


Could anyone give an advice on this? Thank you.

----------------------------------------------------------------------------------------------
Jiøí Voller
Laboratory of Growth Regulators
Palacký University & Institute of Experimental Botany AS CR
©lechtitelù 11, 783 71 Olomouc
Czech Republic
landline: +420-585-634-855
mobile: +420-737-520-506
fax: +420-585-634-870
----------------------------------------------------------------------------------------------

	[[alternative HTML version deleted]]

Hi,

I guess this may be a way to construct a list of character vectors
from variable names.
> library(gregmisc)
> mycolnames <- LETTERS[1:12]
> combinations.2<-combinations(12,2,mycolnames)
> arg.list <- as.list(as.data.frame(t(combinations.2),
stringsAsFactors=FALSE))
> names(arg.list) <- paste("item", seq_len(length(arg.list)),
sep="")
> head(arg.list)
$item1
[1] "A" "B"

$item2
[1] "A" "C"

$item3
[1] "A" "D"

$item4
[1] "A" "E"

$item5
[1] "A" "F"

$item6
[1] "A" "G"

On Nov 25, 2007 5:18 AM, Ji?? Voller <jirivoller at gmail.com>
wrote:
> Dear R-users,
> I would like to construct a list of arguments for a function in a format
> function (list(item1=c("A","B"),
item2=c("B","C")), item3=...):
> The individual vectors in the list are permutations of colnames of a
> dataframe.
> The trouble is that I am not able to handle escaping of parentheses
> correctly.
>
> I was trying the following:
> library(gregmisc)
> combinations.2<-combinations(12,2,mycolnames)
> combinations.2.call<-apply(combinations.2,1,function(x){do.call(paste,c(
> as.list(x),sep="\",\""))})
>
combinations.2.call<-paste("c(\"",combinations.2.call,"\")",sep="")
>
> but now calling call("list",combinations.2.list) doesnt work.
>
>
> Could anyone give an advice on this? Thank you.
>
>
----------------------------------------------------------------------------------------------
> Ji?? Voller
> Laboratory of Growth Regulators
> Palack? University & Institute of Experimental Botany AS CR
> (c)lechtitel? 11, 783 71 Olomouc
> Czech Republic
> landline: +420-585-634-855
> mobile: +420-737-520-506
> fax: +420-585-634-870
>
----------------------------------------------------------------------------------------------
>
>         [[alternative HTML version deleted]]
>
>
> ______________________________________________
> R-help at r-project.org mailing list
> 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.
>
>


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=====================================T.K. (Tae-kyun) Kim
Ph.D. student
Department of Marketing
Marshall School of Business
University of Southern California
======================================