[R] parallel rbind

[William Dunlap]

Oops, I mixed up rbind and cbind.  If LIST consists
of n numeric vectors, each of length p, try
   matrix(unlilst(LIST, use.names=FALSE), nrow=n, byrow=TRUE)

Bill Dunlap
Spotfire, TIBCO Software
wdunlap tibco.com 

> -----Original Message-----
> From: William Dunlap
> Sent: Sunday, August 28, 2011 6:57 PM
> To: 'Steven Bauer'; r-help at r-project.org
> Subject: RE: [R] parallel rbind
> 
> If you know much about what the elements of LIST look like
> you can speed things up by not making R figure out what
> you already know.  E.g., if you know that LIST consists of
> p numeric vectors, all of the same length, n, then the following
> might be faster
>    matrix(unlist(LIST, use.names=FALSE), nrow=n)
> If you are worried about row or column names then you can
> add that information to the call to matrix().  (The above
> will also work if LIST contains some matrix elements, as long as
> they all have n rows.)
> 
> Bill Dunlap
> Spotfire, TIBCO Software
> wdunlap tibco.com
> 
> > -----Original Message-----
> > From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf Of Steven Bauer
> > Sent: Sunday, August 28, 2011 5:36 PM
> > To: r-help at r-project.org
> > Subject: [R] parallel rbind
> >
> > As I am sitting here waiting for some R scripts to run...I was
> > wondering... is there any way to parallelize rbind in R?
> >
> > I wait for this call to complete frequently as I deal with large
> > amounts of data.
> >
> > do.call("rbind", LIST)
> >
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