For each shipped timeslice format, the labels of every level it is built
from, outermost first. d365_h24 for example holds the 365 day labels
(d001..d365) and the 24 hour labels (h00..h23); the timeslice names
themselves are their cross-product.
An object of class list of length 1.
A named list of 7 formats – d364, d365, d366, d364_h24,
d365_h24, d366_h24, m12_h24 – each a list of character vectors, one
per level.
Examples
names(tsl_levels)
#> [1] "d364" "d365" "d366" "d364_h24" "d365_h24" "d366_h24" "m12_h24"
lengths(tsl_levels$d365_h24)
#> YDAY HOUR
#> 365 24