center_interval         Shift to the middle of each interval
closest_weekday         Retrieve the closest given weekday
coffee                  Coffee Data Set
emergency               Emergency Calls for Montgomery County, PA
fill_by_function        Fill missing values by a function of the
                        nonmissings
fill_by_prevalent       Fill missing values by the most prevalent
                        nonmissing value
fill_by_value           Fill missing values by a single value
format_interval         Make a period character vector
get_interval            Get the interval of a datetime variable
pad                     Pad the datetime column of a data frame
pad_cust                Pad with a custom spanning
pad_int                 Pad the integer column of a data frame
span_around             Span an equally spaced vector around a datetime
                        variable
span_date               Wrapper around 'seq.Date'.
span_time               Wrapper around 'seq.POSIXct'.
subset_span             Subset a spanned datetime vector
thicken                 Add a variable of a higher interval to a data
                        frame
thicken_cust            Thicken with a custom spanning
