# [Rd] predict.Arima fails when x is not a time-series

**David Brahm
**
brahm@alum.mit.edu

*Wed, 3 Apr 2002 18:02:21 -0500*

I'm playing with predict.Arima in the 3/19/02 development snapshot of R-devel.
The following produces an error message because x is not of class "ts":
R> x <- rnorm(20)
R> obj <- arima(x, c(2,0,0))
R> predict(obj)
Error in round(x, digits) : Non-numeric argument to mathematical function
Granted the documentation for arima says x should be a time-series, but why not
accommodate simple vectors? I think it would suffice to change this line:
xtsp <- tsp(data)
in predict.Arima to this:
xtsp <- tsp(hasTsp(data))
Also, a minor documentation typo: the help file for predict.Arima refers to the
function as "predict.arima" at one point.
--
-- David Brahm (brahm@alum.mit.edu)
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