epidate: Convert dates into multiple legible formats

In epitools: Epidemiology Tools

Description

Convert character vector of dates into multiple legible formats.

Usage

epidate(x, format = "%m/%d/%Y", cal.dates = FALSE,
        before = 7, after = 7, sunday = TRUE)

Arguments

x	character vector of dates to be converted
format	format of character vector of dates
cal.dates	Calendar dates that contains x, starting 7 days 'before' (default) until 7 days 'after' x
before	defines lower limit of cal.dates: default is 7 days before earliest date in x
after	defines upper limit of cal.dates: default is 7 days after latest date in x
sunday	first day of the week is either Sunday (default) or Monday

Details

Dates can come in many formats (e.g., November 12, 2001, 12Nov01, 11/12/2001, 11/12/01, 2001-11-12) and need to be converted into other formats for data analysis, graphical displays, generating reports, etc.

There is tremendous flexibility in converting any character vector with sufficient information to be converted into a unique date. For complete options for the format option see strptime.

Value

dates	dates wtih date-time class
julian	number of days since 1970-01-01
mday	day of the month: 1-31
mon	month of the year: 0-11
month	month: January, February, March, ...
month2	month: Jan, Feb, Mar, ...
firstday	first day of the week: Sunday or Monday
week	week of the year: 0-53
year	year: YYYY
yr	year: YY
wday	day of the week: 0-6
weekday	weekday: Monday, Tuesday, Wednesday, ...
wkday	weekday: Mon, Tue, Wed, ...
yday	day of the year: 0-365
quarter	quarter of the year: Q1, Q2, Q3, Q4
cdates	Calendar dates that contains dates
cjulian	Julian calendar dates

Author(s)

Tomas Aragon, [e-mail], http://www.phdata.science

References

none

See Also

epitools: as.week

DateTimeClasses to learn about date-time classes

format.Date to convert character vector of dates into calendar dates with date-time class (done by epidate)

strptime to convert date-time character strings into a date-time class

Examples

#x <- c("12/1/03", "11/2/03", NA, "1/7/04", "1/14/04", "8/18/04")
#epidate(x, format = "%m/%d/%y")
#epidate(x, format = "%m/%d/%y", TRUE)
#
###convert vector of disease weeks into vector of mid-week dates
#dwk <- sample(0:53, 100, replace = TRUE)
#wk2date <- paste(dwk, "/", "Wed", sep="")
#wk2date[1:10]
#wk2date2 <- epidate(wk2date, format = "%U/%a")
#wk2date2$dates[1:20]

Example output

epitools documentation built on March 26, 2020, 9:14 p.m.