Check / clean when element

Usage

check_when(when, offset, at)

when: character vector of same length as time (or single value) determining how to interpret the provided sampling time. If NULL will use the dose time as offset (default). Other options are: cmax or peak, which will use the end of infusion as the base for the time, or cmin or trough, which will use the time of next dose as the offset, or middle or cmid which will use the middle between the anchored dose and the next, or random which takes a random time point between the anchored dose and the next.
offset: offset from standardized PK moments specified in when, e.g. c(1, -1) with when = c("peak", "trough") to sample 1 hour after peak and 1 hour before trough.
at: numeric vector of the dose or day number to "anchor" the sampling times to. Vector needs to be of same length as time. If anchor is set to day, then the first dose in that day is used. If later doses in the day are preferred, the anchor can also be specified fractionally, e.g. 1.5 will use the time of the first dose in the second half of the 1st day.