R help - Apr 2011 - as.matrix strangeness

Dear R users,

I presume there is something foul with system:

a <- c(1,2,3,4)
as.matrix(a, ncol=2)

Output:

     [,1]
[1,]    1
[2,]    2
[3,]    3
[4,]    4

The vignette for as.matrix says nrow (ncol) will be deduced from length
and ncol (nrow).  It does not work even when I additionally specify
nrow=2.  It behaves as if I had not given the ncol argument.  Any hints
on what might be borked up here?

R.Version()$ver
[1] "R version 2.10.1 (2009-12-14)"

Thanks in advance,
Michael Bach

Hallo Michael,

check ?matrix and compare to as.matrix.
as.matrix does not provide a ncol argument. To get a 2 by 2 matrix use

matrix(a, ncol=2)

Regards
Adrian

Am 15.04.2011 11:42, schrieb Michael Bach:
> Dear R users,
>
> I presume there is something foul with system:
>
> a<- c(1,2,3,4)
> as.matrix(a, ncol=2)
>
> Output:
>
>       [,1]
> [1,]    1
> [2,]    2
> [3,]    3
> [4,]    4
>
> The vignette for as.matrix says nrow (ncol) will be deduced from length
> and ncol (nrow).  It does not work even when I additionally specify
> nrow=2.  It behaves as if I had not given the ncol argument.  Any hints
> on what might be borked up here?
>
> R.Version()$ver
> [1] "R version 2.10.1 (2009-12-14)"
>
> Thanks in advance,
> Michael Bach
>
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