[R] strange: yaxis inversion with zoo not possible?

[marcg]

hej there

I want to invert the yaxis as follows:

x<-rnorm(1:50)
plot(x^2, type="h", ylim=c(0,10))
plot(x^2, type="h", ylim=c(10,0))

then doing the following it won't work - kind of strange isn't it?

x.zoo<-zoo(x^2)
plot(x.zoo, type="h", ylim=c(10,0))
plot(x.zoo, type="h", ylim=c(0,10))

how can I invert the axis with zoo objects?

Marc
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