Returns an object of class "stl" with the following components:
time.series: a multiple time series with columns seasonal, trend and remainder.
weights: the final robust weights (all one if fitting is not done robustly).
call: the matched call.
win: integer (length 3 vector) with the spans used for the "s", "t", and "l" smoothers.
deg: integer (length 3) vector with the polynomial degrees for these smoothers.
jump: integer (length 3) vector with the 'jumps' (skips) used for these smoothers.
inner: number of inner iterations