[R] time series has no or less than 2 periods

[Rajaraman V]

For decomposing a time series into seasonal components, you need at least 2 
seasons worth of data. If you have even one data point less, you will see 
this error message.

blockLength  <-  52
ts1 <- ts(rnorm(2*blockLength-1), frequency=blockLength)
decompose(ts1)  # error

ts2 <- ts(rnorm(2*blockLength), frequency=blockLength)
decompose(ts2)  # OK