CommencerCommencer gratuitement

Date formats (1)

As you saw earlier, R is picky about how it reads dates. To remind you, as.Date("09/28/2008") threw an error because it was not in the correct format. The fix for this is to specify the format you are using through the format argument:

as.Date("09/28/2008", format = "%m / %d / %Y")
[1] "2008-09-29"

This might look strange, but the basic idea is that you are defining a character vector telling R that your date is in the form of mm/dd/yyyy. It then knows how to extract the components and switch to yyyy-mm-dd.

There are a number of different formats you can specify, here are a few of them:

  • %Y: 4-digit year (1982)
  • %y: 2-digit year (82)
  • %m: 2-digit month (01)
  • %d: 2-digit day of the month (13)
  • %A: weekday (Wednesday)
  • %a: abbreviated weekday (Wed)
  • %B: month (January)
  • %b: abbreviated month (Jan)

Cet exercice fait partie du cours

Intermediate R for Finance

Afficher le cours

Instructions

In this exercise you will work with the date, "1930-08-30", Warren Buffett's birth date!

  • Use as.Date() and an appropriate format to convert "08,30,1930" to a date (it is in the form of "month,day,year").
  • Use as.Date() and an appropriate format to convert "Aug 30,1930" to a date.
  • Use as.Date() and an appropriate format to convert "30aug1930" to a date.

Exercice interactif pratique

Essayez cet exercice en complétant cet exemple de code.

# "08,30,30"
as.Date("08,30,1930", format = ___)

# "Aug 30,1930"
as.Date("Aug 30,1930", format = ___)

# "30aug1930"
as.Date("30aug1930", format = ___)
Modifier et exécuter le code