Extract the entry time, exit time, status or duration of follow-up from a
Lexis
object.
entry(x, time.scale = NULL, by.id=FALSE)
exit(x, time.scale = NULL, by.id=FALSE)
status(x, at="exit" , by.id=FALSE)
dur(x, by.id=FALSE)
an object of class Lexis
.
a string or integer indicating the time scale. If omitted, all times scales are used.
Logical, if TRUE
, only one record per unique value
of lex.id
is returned; either the first, the last or for
dur
, the sum of lex.dur
. If TRUE
, the returned
object have the lex.id
as (row)nmes attribute.
string indicating the time point(s) at which status is to be measured.
The entry
and exit
functions return a vector of
entry times and exit times, respectively, on the requested time
scale. If multiple time scales are requested, then a matrix is
returned.
The status
function returns a vector giving the status
at entry or exit and dur
returns a vector with the lengths
of the follow-up intervals.