A data frame with additional rows for added observation records.
Arguments
data
a data set or event object
times
a vector of observation times
unique
`logical`; if `TRUE` then values for `time` are
dropped if they are found anywhere in `data`
obs_pos
determines sorting order for observations; use `-1` (default)
to put observations first; otherwise, use large integer to ensure
observations are placed after doses
Details
Non-numeric columns will be dropped with a warning.