Extracting parts of a datetime

Working with Dates and Times in R

Charlotte Wickham

Instructor

Extracting parts of a datetime

x <- ymd("2013-02-23")

year(x)

2013

month(x)

2

day(x)

23

Extracting parts of a datetime

Function	Extracts
year()	Year with century
month()	Month (1-12)
day()	Day of month (1-31)
hour()	Hour (0-23)
min()	Minute (0-59)
second()	Second (0-59)
wday()	Weekday (1-7)
yday()	Day of year a.k.a. Julian day (1-366)
tz()	Timezone

Setting parts of a datetime

x

"2013-02-23"

year(x) <- 2017x

"2017-02-23"

Other useful functions

Function	Extracts
leap_year()	In leap year (TRUE or FALSE)
am()	In morning (TRUE or FALSE)
pm()	In afternoon (TRUE or FALSE)
dst()	During daylight savings (TRUE or FALSE)
quarter()	Quarter of year (1-4)
semester()	Half of year (1-2)

Let's practice!

Working with Dates and Times in R