[R] creating empty cells with table()

[Romain Francois]

Le 19.04.2006 15:21, Owen, Jason a écrit :
> Hello,
>
> Suppose I simulate 20 observations from the Poisson distribution
> with lambda = 4.  I can summarize these values using table() and
> then feed that to barplot() for a graph.
>
> Problem: if there are empty categories (e.g. 0) or empty categories
> within the range of the data (e.g. observations for 6, 7, 9), barplot()
> does not include the empty cells in the x-axis of the plot.  Is there
> any way to specify table() to have specific categories (in the above
> example, probably 0:12) so that zeroes are included?
>
> Thanks,
>
> Jason
>   
Hi,

What about using ?factor with its levels argument :

x <- rpois(30, lambda=4)
table(factor(x,levels=0:12))

Romain

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| Romain FRANCOIS - http://francoisromain.free.fr               |
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