Time Series

["Koken.Petra" <koken@niehs.nih.gov>]

Dear Colleagues,

Could anyone tell me how I can aggregate a daily time series to a
monthly one? I am working with S-Plus 2000 and the syntax of aggregate
has changed. The "by" argument that could be used in earlier versions
of S-plus is not allowed anymore. There is however, a new "nf" option
but frequency for aggregated time series must be a divisor of the
frequency of x, which is not the case with months.

Thank you very much,

Petra Koken