[R] Applying do.call to a data.frame using function arguments

[William Dunlap]

> -----Original Message-----
> From: r-help-bounces at r-project.org 
> [mailto:r-help-bounces at r-project.org] On Behalf Of miller_2555
> Sent: Wednesday, August 26, 2009 9:32 AM
> To: r-help at r-project.org
> Subject: Re: [R] Applying do.call to a data.frame using 
> function arguments
> 
> 
> 
> miller_2555 wrote:
> > 
> > I'm trying to convert a data.frame to a series of strings 
> (row-wise).
> > There was a very good discussion awhile back (2002) 
> entitled "[R] string
> > concatenate across rows of a matrix??" where Tony Plate 
> recommended the
> > following two alternatives (x2 is an R object of type data 
> frame -- a
> > matrix also works for solution #1): 
> >     1) apply(format(x2), 1, paste, collapse=" ");
> >     2) do.call("paste",x2)
> > 
> 
> Nevermind. Stupid question. The solution is:
> do.call("paste",c(x2,sep='","')); 

This works most of the time but will fail if your
data.frame has a column called "sep" or "collapse"
(the named arguments to paste()).  Changing
x2 to unname(x2) or unname(as.list(x2)) makes it
more bulletproof.

Bill Dunlap
TIBCO Software Inc - Spotfire Division
wdunlap tibco.com 

> 
> Hope this helps somebody.
> -- 
> View this message in context: 
> http://www.nabble.com/Applying-do.call-to-a-data.frame-using-f
> unction-arguments-tp25151441p25151445.html
> Sent from the R help mailing list archive at Nabble.com.
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