[R] matrix in data.frame

[Prof Brian Ripley]

You need to use I() or something similar. E.g.

A <- matrix(1:6, 2,3)
data.frame(x=1:2, I(A))

X <- data.frame(x=1:2)
X$A <- A

both insert A as a single column.


On Wed, 30 May 2007, Lina Hultin-Rosenberg wrote:

> Dear list!
>
> I have run into a problem that seems very simple but I can't find any
> solution to it (have searched the internet, help-files and "An introduction
> to R" etc without any luck). The problem is the following: I would like to
> create a data.frame with two components (columns), the first component being
> a matrix and the second component a vector. Whatever I have tried so far, I
> end up with a data.frame containing all the columns from the matrix plus the
> vector which is not what I am after. I have seen this kind of data.frame
> among R example datasets (oliveoil and yarn).
>
> I would greatly appreciate some help with this problem!
>
> Kind regards,
>
> Lina Hultin Rosenberg
> Karolinska Biomics Center
> Karolinska Institute
> Sweden

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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