[R] Returning data in matrix form

[Jonathan Baron]

On 01/19/04 19:27, Laura Quinn wrote:
>I am trying to perform the following calculation for a very
>large time series data set:
>
>x<-unit(length*data.frame.a*data.frame.b,"cm")
>
>data.frame.a and data.frame.b are of the same dimension, and I wish to
>perform the calculation in one step so that "x" is returned as a
>matrix/data.frame of equal dimension.

Sounds like mapply() would be useful.  It works on columns of
data frames.  The default is "simplify=TRUE" so it will try to
return a vector or matrix.

Jon
--
Jonathan Baron, Professor of Psychology, University of Pennsylvania
Home page:            http://www.sas.upenn.edu/~baron
R page:               http://finzi.psych.upenn.edu/