Windows a tis or ts time series to cut off leading and trailing
NA (and optionally zero) observations.
naWindow(x, union = F, zero = F)a tis or ts time series
see details below
if TRUE, chop off leading and trailing zeroes also
A copy of x with leading and trailing NA observations deleted.
For multivariate (multiple columns) series and union = TRUE, a
row of x is considered to be NA if and only if all entries in
that row are NA. If union = FALSE (the default), a row is
considered to be NA if any of its entries is NA.
if zero is TRUE, the function chops off leading and
trailing observations that are either NA or zero. Otherwise,
it chops only NAs.