The periodic component is specified by one and only one of s
,
om
, and tau
. When s
is given, the function
assumes that the period is an integer, while a period specified by
tau
is assumed to be noninteger. Instead of tau
,
the frequency om
can be specified. The argument q
specifies the number of harmonics to include in the model. When
tau
or omega
is given, then q
is required as
well, since in this case the implied Fourier representation has
infinitely many harmonics. On the other hand, if s
is given,
q
defaults to all the harmonics in the Fourier representation,
that is floor(s/2)
.
The system variance of the resulting dlm is dW
times the identity
matrix of the appropriate dimension.