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lubridate (version 1.9.4)

day: Get/set days component of a date-time

Description

Get/set days component of a date-time

Usage

day(x)

mday(x)

wday( x, label = FALSE, abbr = TRUE, week_start = getOption("lubridate.week.start", 7), locale = Sys.getlocale("LC_TIME") )

qday(x)

yday(x)

day(x) <- value

mday(x) <- value

qday(x) <- value

qday(x) <- value

wday(x, week_start = getOption("lubridate.week.start", 7)) <- value

yday(x) <- value

Value

wday() returns the day of the week as a decimal number or an ordered factor if label is TRUE.

Arguments

x

a POSIXct, POSIXlt, Date, chron, yearmon, yearqtr, zoo, zooreg, timeDate, xts, its, ti, jul, timeSeries, or fts object.

label

logical. Only available for wday. TRUE will display the day of the week as an ordered factor of character strings, such as "Sunday." FALSE will display the day of the week as a number.

abbr

logical. Only available for wday. FALSE will display the day of the week as an ordered factor of character strings, such as "Sunday." TRUE will display an abbreviated version of the label, such as "Sun". abbr is disregarded if label = FALSE.

week_start

day on which week starts following ISO conventions: 1 means Monday and 7 means Sunday (default). When label = FALSE and week_start = 7, the number returned for Sunday is 1, for Monday is 2, etc. When label = TRUE, the returned value is a factor with the first level being the week start (e.g. Sunday if week_start = 7). You can set lubridate.week.start option to control this parameter globally.

locale

locale to use for day names. Default to current locale.

value

(for wday<-) a numeric or a string giving the name of the day in the current locale or in English. Can be abbreviated. When a string, the value of week_start is ignored.

Details

mday() and yday() return the day of the month and day of the year respectively. day() and day<-() are aliases for mday() and mday<-().

Examples

Run this code
x <- as.Date("2009-09-02")
wday(x) # 4
wday(x, label = TRUE) # Wed

wday(x, week_start = 1) # 3
wday(x, week_start = 7) # 4

wday(x, label = TRUE, week_start = 7) # Wed (Sun is the first level)
wday(x, label = TRUE, week_start = 1) # Wed (Mon is the first level)

wday(ymd(080101))
wday(ymd(080101), label = TRUE, abbr = FALSE)
wday(ymd(080101), label = TRUE, abbr = TRUE)
wday(ymd(080101) + days(-2:4), label = TRUE, abbr = TRUE)

x <- as.Date("2009-09-02")
yday(x) # 245
mday(x) # 2
yday(x) <- 1 # "2009-01-01"
yday(x) <- 366 # "2010-01-01"
mday(x) > 3

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