The line list columns that contain <Date> objects are stored at double
point precision by default. In other words, they are not integer values,
so can be part way through a day. The exact numeric value of the <Date>
can be seen if you unclass() it.
Censoring line list dates reduces the time precision (window) of the event.
Often dates of events, such as symptom onset or hospital admission are only
known to the nearest day, not hour or minute. Other events may be more
coarsely censored, for example to the nearest week or month.
censor_linelist() converts the exact double point precision event
<Date> to the time interval specified.
Depending on the interval specified, the date columns will be returned
as different objects. Here is a list of the valid input interval and the
resulting class of the date column.
integer -> <grates_period> (see grates::as_period())
"daily" -> <Date> (see Date)
"weekly" -> <grates_isoweek> (see grates::as_isoweek())
"epiweek" -> <grates_epiweek> (see grates::as_epiweek())
"monthly" -> <grates_yearmonth> (see grates::as_yearmonth())
"yearly" -> <grates_year> (see grates::as_year())