Tena koe Judit
If it is really a matrix (and not a data.frame) and you wish to change a
randomly selected zero to a one, then
judit <- matrix(0, nrow=3, ncol=4)
judit[sample(1:length(judit), 1)] <- 1
will do. This uses the fact that a matrix is a vector with a dim attribute.
HTH ....
Peter Alspach
> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Barroso, Judit
> Sent: Wednesday, 10 November 2010 10:50 a.m.
> To: r-help at r-project.org
> Subject: [R] Change a value in a matrix randomly
>
> I have a matrix of ceros, for example:
> 0 0 0 0
> 0 0 0 0
> 0 0 0 0
> And I would like that one of these values turn into 1, for example if
> one condition is got, but not in a concrete position if not randomly.
> Could you indicate me the code to can get it?
>
> Thanks in advance,
> Judit Barroso
>
> [[alternative HTML version deleted]]
>
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> and provide commented, minimal, self-contained, reproducible code.
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