DayName

DayName[]

gives the current day of the week.

DayName[date]

gives the day of the week for the given date.

Details and Options

  • The following options can be given:
  • CalendarType"Gregorian"calendar in which the date parameter has been specified

Examples

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Basic Examples  (3)

The day of the week for a particular date:

The day of the week today:

Hours, minutes, and seconds do not affect the day of the week:

Options  (4)

CalendarType  (4)

Louis XIV was born on a Sunday:

The Greek Orthodox liturgy uses the Julian calendar. The Orthodox Christmas 2000 was on a Sunday:

By definition, Yom Kippur cannot fall on a Friday or Sunday:

The first of January of year 1 in the proleptic Gregorian calendar was a Monday:

It was a Saturday in the Julian calendar:

Applications  (2)

The 400-year cycle of the Gregorian calendar includes an integral number of weeks:

There are 20871 weeks in those 400 years because there are 97 leap days in the cycle:

A century never begins on a Sunday:

No matter how the beginning of a century is defined:

Properties & Relations  (2)

Conway's Doomsday rule observes that certain dates within a Gregorian calendar year will always fall on the same day of the week, including the last day of February, the 4th day of the 4th month, the 6th day of the 6th month, and others:

Conway calls this the doomsday of the year, which is Tuesday for 2017:

Thursday, October 4 in the Julian calendar was followed by Friday, October 15 in the Gregorian calendar:

Neat Examples  (1)

This computes the number of times each day of the week occurs as a 13th of the month over the complete 400-year cycle of the Western (Gregorian) calendar:

The 13th of the month falls more often on a Friday than on any other day of the week:

Introduced in 2012
 (9.0)
 |
Updated in 2014
 (10.0)