Discordian date

Discordian date
You are encouraged to solve this task according to the task description, using any language you may know.

Convert a given date from the Gregorian calendar to the Discordian calendar.

See Also

• Discordian calendar (wiki)

F#

<lang F#>open System

let seasons = [| "Chaos"; "Discord"; "Confusion"; "Bureaucracy"; "The Aftermath" |]

let ddate (date:DateTime) =

   let dyear = date.Year + 1166
   let leapYear = DateTime.IsLeapYear(date.Year)
   
   if leapYear && date.Month = 2 && date.Day = 29 then
       sprintf "St. Tib's Day, %i YOLD" dyear
   else
       // compensate for St. Tib's Day
       let dayOfYear = if leapYear && date.DayOfYear >= 60 then date.DayOfYear - 1 else date.DayOfYear
       let season, dday = Math.DivRem(dayOfYear, 73)
       sprintf "%s %i, %i YOLD" seasons.[season] dday dyear</lang>

Haskell

<lang haskell>import Data.List import Data.Time import Data.Time.Calendar.MonthDay

seasons = words "Chaos Discord Confusion Bureaucracy The_Aftermath"

discordianDate (y,m,d) = do

 let doy = monthAndDayToDayOfYear (isLeapYear y) m d
     (season, dday) = divMod doy 73
     dos = dday - fromEnum (isLeapYear y && m >2)
     dDate

| isLeapYear y && m==2 && d==29 = "St. Tib's Day, " ++ show (y+1166) ++ " YOLD" | otherwise = seasons!!season ++ " " ++ show dos ++ ", " ++ show (y+1166) ++ " YOLD"

 putStrLn dDate</lang>

Examples:

*Main> mapM_ discordianDate [(2012,2,28),(2012,2,29),(2012,3,1),(2010,9,2),(2010,12,6)]
Chaos 59, 3178 YOLD
St. Tib's Day, 3178 YOLD
Chaos 60, 3178 YOLD
Bureaucracy 26, 3176 YOLD
The_Aftermath 48, 3176 YOLD

In GHCi we can also execute shell commands.

• Using Linux utility ddate

*Main> :! ddate
Today is Setting Orange, the 26th day of Bureaucracy in the YOLD 3176

*Main> :! ddate 29 2 2012
Sint Tibs

*Main> :! ddate 2 9 2010
Setting Orange, Bureaucracy 26, 3176 YOLD

J

<lang j>leap=: _1j1 * 0 -/@:= 4 100 400 |/ {.@] bs=: ((#:{.) + 0 j. *@[ * {:@]) +. disc=: ((1+0 73 bs[ +^:(58<]) -/@todayno@(,: 1 1,~{.)@]) ,~1166+{.@])~ leap</lang>

Example use:

<lang> disc 2012 2 29 3178 1 59j1</lang>

see talk page.

PicoLisp

Translation of: Python

<lang PicoLisp>(de disdate (Year Month Day)

  (let? Date (date Year Month Day)
     (let (Leap (date Year 2 29)  D (- Date (date Year 1 1)))
        (if (and Leap (= 2 Month) (= 29 Day))
           (pack "St. Tib's Day, YOLD " (+ Year 1166))
           (and Leap (>= D 60) (dec 'D))
           (pack
              (get
                 '("Chaos" "Discord" "Confusion" "Bureaucracy" "The Aftermath")
                 (inc (/ D 73)) )
              " "
              (inc (% D 73))
              ", YOLD "
              (+ Year 1166) ) ) ) ) )</lang>

PureBasic

<lang PureBasic>Procedure.s Discordian_Date(Y, M, D)

 Protected DoY=DayOfYear(Date(Y,M,D,0,0,0)), Yold$=Str(Y+1166)
 Dim S.s(4)
 S(0)="Chaos": S(1)="Discord": S(2)="Confusion": S(3)="Bureaucracy"
 S(4)="The Aftermath"
 If (Y%4=0 And Y%100) Or Y%400=0
   If M=2 And D=29
     ProcedureReturn "St. Tib's Day, YOLD " + Yold$
   ElseIf DoY>=2*30
     DoY-1
   EndIf
 EndIf
 ProcedureReturn S(DoY/73)+" "+Str(DoY%73)+", Yold "+Yold$

EndProcedure</lang>

Python

<lang python>import datetime, calendar

DISCORDIAN_SEASONS = ["Chaos", "Discord", "Confusion", "Bureaucracy", "The Aftermath"]

def ddate(year, month, day):

   today = datetime.date(year, month, day)
   is_leap_year = calendar.isleap(year)
   if is_leap_year and month == 2 and day == 29:
       return "St. Tib's Day, YOLD " + (year + 1166)
   
   day_of_year = today.timetuple().tm_yday - 1
   
   if is_leap_year and day_of_year >= 60:
       day_of_year -= 1 # Compensate for St. Tib's Day
   
   season, dday = divmod(day_of_year, 73)
   return "%s %d, YOLD %d" % (DISCORDIAN_SEASONS[season], dday + 1, year + 1166)

</lang>

Scala

Translation of: Python

<lang scala>import java.util.{GregorianCalendar, Calendar}

val DISCORDIAN_SEASONS=Array("Chaos", "Discord", "Confusion", "Bureaucracy", "The Aftermath") def ddate(year:Int, month:Int, day:Int):String={

  val date=new GregorianCalendar(year, month-1, day)
  val dyear=year+1166

  val isLeapYear=date.isLeapYear(year)
  if(isLeapYear && month==2 && day==29)
     return "St. Tib's Day "+dyear+" YOLD"

  var dayOfYear=date.get(Calendar.DAY_OF_YEAR)
  if(isLeapYear && dayOfYear>=60)
     dayOfYear-=1	// compensate for St. Tib's Day

  val dday=dayOfYear%73
  val season=dayOfYear/73
  "%s %d, %d YOLD".format(DISCORDIAN_SEASONS(season), dday, dyear)

}</lang>

Tcl

<lang tcl>package require Tcl 8.5 proc disdate {year month day} {

   # Get the day of the year
   set now [clock scan [format %02d-%02d-%04d $day $month $year] -format %d-%m-%Y]
   scan [clock format $now -format %j] %d doy

   # Handle leap years
   if {!($year%4) && (($year%100) || !($year%400))} {

if {$doy == 60} { return "St. Tib's Day, [expr {$year + 1166}] YOLD" } elseif {$doy > 60} { incr doy -1 }

   }

   # Main conversion to discordian format now that special cases are handled
   incr doy -1; # Allow div/mod to work right
   set season [lindex {Chaos Discord Confusion Bureaucracy {The Aftermath}} \

[expr {$doy / 73}]]

   set dos [expr {$doy % 73 + 1}]
   incr year 1166
   return "$season $dos, $year YOLD"

}</lang> Demonstrating: <lang tcl>puts [disdate 2010 7 22]; # Today puts [disdate 2012 2 28] puts [disdate 2012 2 29] puts [disdate 2012 3 1]</lang> Output:

Confusion 57, 3176 YOLD
Chaos 59, 3178 YOLD
St. Tib's Day, 3178 YOLD
Chaos 60, 3178 YOLD