Subset data to the rows used for calculations within an interval

Rows are selected by their time falling within the interval: start <= time and time <= end (or time < end when include_end=FALSE). For duration data (for example, urine collections or intravenous infusions), time is the start of the collection or administration, and the duration column is not consulted during selection: a record whose duration starts within the interval and ends after the interval end is selected and contributes its full amount to calculations within the interval. For the simplest interpretation of results, align collection start and end times with interval boundaries.

Usage

filter_interval(data, start, end, include_na = FALSE, include_end = TRUE)

Arguments

data

A data.frame with a column named time (and, for duration data, a column named duration, which is ignored during selection)

start, end

The beginning and end times of the interval

include_na

Should rows with an NA time be kept?

include_end

Should a row with time == end be kept?

Value

The rows of data selected for the interval