R – Time, lubridate

EXTRACT:

month(date, label = TRUE, abbr = TRUE): label showing the names of the month
year
day
yday 1 to 366
wday

ROUND
floor_date
round_date
ceiling_date

INTERVAL
(start time) %–% (end time)
int_end
int_start
int_length

%within%
int_overlaps

as.period() – convert interval to period
as.duration() – convert interval to duration

TIMEZONE
force_tz(time, tzone = “”)
with_tz(time, tzone = “”)

IMPORT
parse_date_time(time, order = “ymd”)
fast_strptime(time, order = “%Y-%m-%d”), same format as strptime()
fasttime(), fastPOSIXct()

stamp(string) return format of time string %Y %d etc.

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